Antioxidant Activity of Humulus lupulus Phenolic Hop Extracts in Creating a New Pâté: An Element Affecting Fat Stability and Microbiological Quality during Storage

The aim of this study was to evaluate the effect of hop extracts on changes in the primary and secondary fat oxidation products, physicochemical properties, and microbiological quality of pâté-type offal sausages obtained through the partial replacement of animal fat with vegetable fat. This study demonstrated that the extraction efficiency varied among hop cone varieties, with the highest efficiency observed for the Lubelski variety and the lowest for the Magnum variety. The phenolic compound content was higher in the Magnum cones (2.74 ± 0.11 mg/g dry matter) compared to the Lubelska cones (2.27 ± 0.05 mg/g of product). Additionally, the DPPH radical scavenging activity was greater in the extract from the Magnum cones (4.21 ± 0.09 mg TE/g d.w.) than in the extract from the Lublelski cones (3.87 ± 0.05 mg TE/ g d.w.). Similarly, the extracts from the Lubelski cones exhibited a higher antiradical activity against the ABTS radical compared to the extract from Magnum cones. Throughout storage, a significant increase in the pH value was observed in the control sample and in the samples with a 20% replacement of animal fat with rapeseed oil and Magnum hop extract. However, the addition of Lubelski hop extract resulted in a decrease in the pH value during the 15-day storage period. The samples with a 20% replacement of animal fat with rapeseed oil and 0.1% Lubelski hop extract showed the least changes in water activity during storage. The samples with a 20% replacement of animal fat with rapeseed oil and the addition of 0.2% Lubelski hop extract had the lowest peroxide value and TBARS index throughout the storage period. The addition of hop extract inhibited the growth of the total number of microorganisms in the tested sausages. In the samples with a 20% replacement of animal fat with rapeseed oil, the content of aerobic microorganisms, compared to the control sample, was statistically significantly lower.

A Study of Resistome in Mexican Chili Powder as a Public Health Risk Factor

Chili powder is an important condiment around the world. However, according to various reports, the presence of pathogenic microorganisms could present a public health risk factor during its consumption. Therefore, microbiological quality assessment is required to understand key microbial functional traits, such as antibiotic resistance genes (ARGs). In this study, metagenomic next-generation sequencing (mNGS) and bioinformatics analysis were used to characterize the comprehensive profiles of the bacterial community and antibiotic resistance genes (ARGs) in 15 chili powder samples from different regions of Mexico. The initial bacterial load showed aerobic mesophilic bacteria (AMB) ranging between 6 × 103 and 7 × 108 CFU/g, sporulated mesophilic bacteria (SMB) from 4.3 × 103 to 2 × 109 CFU/g, and enterobacteria (En) from <100 to 2.3 × 106 CFU/g. The most representative families in the samples were Bacillaceae and Enterobacteriaceae, in which 18 potential pathogen-associated species were detected. In total, the resistome profile in the chili powder contained 68 unique genes, which conferred antibiotic resistance distributed in 13 different classes. Among the main classes of antibiotic resistance genes with a high abundance in almost all the samples were those related to multidrug, tetracycline, beta-lactam, aminoglycoside, and phenicol resistance. Our findings reveal the utility of mNGS in elucidating microbiological quality in chili powder to reduce the public health risks and the spread of potential pathogens with antibiotic resistance mechanisms.

Anti-Salmonella Activity of Thymus serpyllum Essential Oil in Sous Vide Cook-Chill Rabbit Meat

Food is generally prepared and vacuum-sealed in a water bath, then heated to a precise temperature and circulated in a sous vide machine. Due to its affordability and ease of use, this cooking method is becoming increasingly popular in homes and food service businesses. However, suggestions from manufacturers and chefs for long-term, low-temperature sous vide cooking raise questions about food safety in the media. In this study, heat treatment with different times and wild thyme essential oil (EO) in sous vide-processed rabbit longissimus dorsi muscle were found to inactivate Salmonella enterica. The rabbit meat samples were vacuum-packed in control groups, in the second group the rabbit meat samples were injected with S. enterica, and in the third group were meat samples infected with S. enterica with Thymus serpylum EO additive. The vacuum-packed samples were cooked sous vide for the prescribed time at 55, 60, and 65 °C. At 5, 15, 30, and 60 min, the quantities of S. enterica, total bacterial counts, and coliform bacteria were measured in groups of sous vide rabbit meat. Microbiological analyses of rabbit meat samples on days 1 and 7 were evaluated. In this study, total viable counts, coliforms bacteria, and number of Salmonella spp. were identified. After incubation, isolates from different groups of microorganisms were identified by the mass spectrometry technique. For each day measured, the test group exposed to a temperature of 55 °C for 5 min had a greater number of total microbiota. The most isolated microorganisms by MALDI-TOF MS Biotyper from the control and treated groups were Lactococcus garvieae and in the treated groups also S. enterica. Based on our analysis of sous vide rabbit meat samples, we discovered that adding 1% of thyme essential oil to the mixture reduced the amount of Salmonella cells and increased the overall and coliform bacterial counts. The microbiological quality of sous vide rabbit meat that was kept for seven days was positively impacted by the addition of thyme essential oil.

Strategies to improve the postharvest management of flat oyster (Ostrea edulis) from aquaculture using the short-term storage and package in an innovative closed-circuit system

This study aimed to improve postharvest management of flat oysters reared in a longline system in the mid Adriatic Sea, using short-term storage and package in an innovative closed-circuit system. For the trial, 870 oysters were employed, divided into three experimental groups (A, B, and C), N = 270 oysters each group, whereas the remaining 60 oysters were used for the 2 controls. Each group differed in relation to the time spent in the depuration tank and the time of packaging: group A was packed and immediately transferred to the cell; group B was depurated in a tank for 48 h, then packed and transferred to the cell; group C was depurated in a tank for 48 h and then packed, depurated for another 24 h and transferred to a cell. Samples of each group were sampled at different times of permanence in cell (t0) up until 12 days (t12) for biomorphometric, sensorial, nutritional, and microbiological analysis. Although the nutritional and sensorial quality of the oysters was more pronounced in group A, B and C groups also showed good results. In these two groups, thanks to the use of the modern water recirculation system the quality and safety of oysters was improved by reducing the presence of sludge and eliminating fecal contaminants completely than A treatment and seawater control. These results were also confirmed by the tank control, where a more extended depuration period positively influenced the same parameters emphasizing the importance of the adequate depuration processes in oyster production.

Quality Assessment of Minced Poultry Products Including Black Fermented Garlic

The aim of this study was to evaluate the effect of the addition of fermented black garlic on the quality of minced poultry products. Treatments were organized in four groups (1%, 2%, 3%, and 4%) containing either black fermented garlic (bg) or fresh garlic (fg), and a control (produced without garlic). The quality assessment of minced poultry products included physicochemical properties (weight losses, pH, colour and shear force), microbiological quality (Enterobacteriaceae, total count of bacteria, lactic acid bacteria, and Pseudomonas spp.) and evaluation of sensory attributes. The results showed that the pH values in the black garlic groups, pH 6.06, 6.03, and 6.01, were lower than in the control group, pH 6.16, and tended to decrease during the period of cold storage. As the percentage of black garlic increased, there was a decrease in pH, the value of L* (brightness) from 76.16 in the control group to 48.03 in the group with 4% bg, while the value of b* (yellowing) increased analogously from 12.59 to 16.08. The use of black fermented garlic at 2% as a substitute for fresh garlic is a viable alternative to obtaining product with an acceptable taste and aroma. The addition of 4% black garlic was not acceptable to the assessors.

Dried Herbs as an Easy-to-Use and Cost-Effective Alternative to Essential Oils to Extend the Shelf Life of Sheep Lump Cheese

The objective of this research was to assess the effectiveness of three specific dried herbs (rosemary, thyme, and oregano) in combating microbial spoilage in sheep lump cheese. This was achieved by comparing them with a control group and cheeses treated with corresponding 1% essential oils (Rosmarinus officinalis, Origanum vulgare, Thymus vulgaris). All cheese samples were vacuum-sealed and stored at 4 °C for 15 days. Analysis of total viable counts of viable bacteria (TVC), coliform bacteria (CB), lactic acid bacteria (LAB), and microscopic filamentous fungi (MFF) was conducted on days 0, 5, 10, and 15. The results revealed that, at the end of the storage period, dried oregano-treated samples exhibited the lowest TVC count (5.80 log CFU/g), while dried rosemary-treated samples showed the lowest CB count (3.27 log CFU/g). Moreover, the lowest MFF count (2.40 log CFU/g) was observed in oregano essential oil-treated samples. Additionally, dried oregano-treated samples displayed the highest LAB count (4.49 log CFU/g) at the experiment's conclusion. Furthermore, microorganism identification from sheep cheese was performed using MALDI-TOF MS Biotyper technology, revealing that the most frequently isolated bacteria were Citrobacter braakii and Hafnia alvei (Enterobacteriaceae family), along with Lacticaseibacillus paracasei (Lactobacillaceae family). In summary, all the natural substances examined exhibited inhibitory effects against the studied microorganisms, with oregano essential oil and dried oregano demonstrating the strongest inhibitory effects. This supports their potential use as cost-effective natural preservatives to extend the shelf life of sheep lump cheese.

An innovative application developed to determine the blood output of chickens and its impact on the meat quality in poultry slaughtering

Optimizing blood loss during the slaughtering process is crucial for obtaining high-quality meat, as the presence of meat blood can lead to a reduction in shelf life and negative sensory evaluation by consumers. Moreover, the high water and nutritional content of the meat, along with its appropriate pH value, necessitate careful consideration of the remaining blood, as it can support microbial spoilage of chicken meat. In this context the effects of making an extra cut on conventionally halal-slaughtered broiler's leg which had an extra cut at the cartilage point where the drumstick and the claw part meet, before the bloodletting process were analysed. The results of the analysis indicate that making an additional cut on the drumsticks does not adversely affect the overall quality of chicken meat. Determination of peroxide value (PV) and thiobarbituric acid reactive substance (TBARS) analyses were performed to analyze the degree of lipid oxidation. The PV and the TBARS value were higher in the drumsticks which have extra cut compared to the uncut samples. L*, a*, and b* values of extra cut thigh meats are higher. However, considering the storage period, the ninth day values in the cut thigh meats were found to be lower than the first day results of the chickens drumsticks do not have an extra cut procedure. As the storage period of chicken drumsticks progressed, as expected, the L* value decreased, while a* value and b* value increased over time. As regards sexes of broilers, it was observed that the Pseudomonas spp of female broilers with extra cut in the cartilage tissue of their legs on d 1 was significantly higher than the male broilers. These findings suggest that this innovative method holds significant potential for widespread application.

Ancient Grain Flours with Different Degrees of Sifting: Advances in Knowledge of Nutritional, Technological, and Microbiological Aspects

Ancient grains have gained considerable attention in recent years, as some research suggests they may be healthier than modern wheat. The present study aims to evaluate the chemical, rheological, and microbiological features of three Southern Italian cultivated ancient wheat varieties: Risciola, Carosella, and Saragolla. ATR-FTIR analyses were performed on the finely ground grain samples of the three varieties. The selected grains were ground with a stone mill, and different sifting degrees (whole-100%, type 1-80%, and type 0-72%) were evaluated. The flours showed a good nutritional profile, a higher amylose/amylopectin ratio, and a lower glycemic index than the literature. The gluten index of the samples was in the range 2.6-28.9%, and the flours can be classified as weak, having a value <30%. The farinographic test showed a short development time, low dough stability, a high softening degree, and water absorption, which increased with the degree of sifting. Microbiological analyses performed on flours from ancient grains at different degrees of sifting show their safety, according to their microbiological parameters, which fall within the legal microbiological requirements established by the European Commission Regulation (EC).

Microbiological Quality of Australian Beef, Sheep and Pork Carcases, Cuts and Offals

A one-year survey was undertaken of the microbiological quality of carcases and the derived primal cuts, manufacturing meat and offals at twelve Australian export establishments (six beef, three sheep/lamb and three pork). A total of 27,157 microbiological results for aerobic plate count (APC) and generic Escherichia coli were gathered, 15,155 from beef, 8405 from sheep and 3597 from pig establishments. The mean log10 APCs on beef, sheep and pig carcases were 0.84, 1.60 and 1.30 log10 cfu/cm2, respectively. For primals, the mean log10 APC was higher for beef but was similar for sheep and pork primals, with 'outside' cuts having higher counts. For manufacturing meat, the concentration was 2-3 log10 cfu/g, irrespective of species. The prevalence (%) of generic E. coli from beef, sheep and pork was 2.3, 28.4 and 5.4 on carcases; 7.0, 20.6 and 3.2 on primals; and 5.8, 33.6 and 6.1 on manufacturing meat, respectively. The mean log10 APCs of beef, sheep and pork offal were 3.23, 3.18 and 3.37 log10 cfu/g, with tripes and tongues having APCs 1-2 log10 units higher than organ offals. The results reflect improvements in total bacterial loadings compared with previous national baseline surveys.

The Biochemical, Microbiological, Antioxidant and Sensory Characterization of Fermented Skimmed Milk Drinks Supplemented with Probiotics Lacticaseibacillus casei and Lacticaseibacillus rhamnosus

A variety of foods fermented with lactic acid bacteria (LAB) serve as dietary staples in many countries. The incorporation of health-promoting probiotics into fermented milk products can have profound effects on human health. Considering the health benefits of Yakult, the current study was undertaken to develop an enriched Yakult-like fermented skimmed milk drink by the addition of two probiotic strains, namely Lacticaseibacillus casei (Lc) and Lacticaseibacillus rhamnosus (Lr). The prepared drinks were compared in terms of various parameters, including their physicochemical properties, proximate chemical composition, mineral estimation, microbial viable count, antioxidant activity, and sensory evaluation. Each strain was employed at five different concentrations, including 1% (T1), 1.5% (T2), 2% (T3), 2.5% (T4), and 3% (T5). The prepared Yakult samples were stored at 4 °C and analyzed on days 0, 7, 14, 21, and 28 to evaluate biochemical changes. The findings revealed that the concentration of the starter culture had a significant (p ≤ 0.05) impact on the pH value and moisture and protein contents, but had no marked impact on the fat or ash content of the developed product. With the Lc strain, Yakult's moisture content ranged from 84.25 ± 0.09 to 85.65 ± 0.13%, whereas with the Lr strain, it was from 84.24 ± 0.08 to 88.75 ± 0.13%. Protein levels reached their highest values with T5 (3% concentration). The acidity of all treatments increased significantly due to fermentation and, subsequently, pH showed a downward trend (p ≤ 0.05). The total soluble solids (TSS) content decreased during storage with Lc as compared to Lr, but the presence of carbohydrates had no appreciable impact. The drink with Lc exhibited a more uniform texture and smaller pore size than Yakult with Lr. Except for the iron values, which showed an increasing trend, the contents of other minerals decreased in increasing order of the added probiotic concentration used: 1% (T1), 1.5% (T2), 2% (T3), 2.5% (T4), and 3% (T5). The highest lactobacilli viable count of 8.69 ± 0.43 colony-forming units (CFU)/mL was observed with the T1 Lr-containing drink at the end of the storage period. Regarding the storage stability of the drink, the highest value for DPPH (88.75 ± 0.13%) was found with the T1 Lc drink on day 15, while the highest values for FRAP (4.86 ± 2.80 mmol Fe2+/L), TPC (5.97 ± 0.29 mg GAE/mL), and TFC (3.59 ± 0.17 mg GAE/mL) were found with the T5 Lr drink on day 28 of storage. However, the maximum value for ABTS (3.59 ± 0.17%) was noted with the T5 Lr drink on the first day of storage. The results of this study prove that Lc and Lr can be used in dairy-based fermented products and stored at refrigerated temperatures.

Marinades Based on Natural Ingredients as a Way to Improve the Quality and Shelf Life of Meat: A Review

Marinating is a traditional method of improving the quality of meat, but it has been modified in response to consumer demand for "clean label" products. The aim of this review is to present scientific literature on the natural ingredients contained in marinades, the parameters of the marinating process, and certain mechanisms that bring about changes in meat. A review was carried out of publications from 2000 to 2023 available in Web of Science on the natural ingredients of meat marinades: fruit and vegetables, seasonings, fermented dairy products, wine, and beer. The review showed that natural marinades improve the sensory quality of meat and its culinary properties; they also extend its shelf life. They affect the safety of meat products by limiting the oxidation of fats and proteins. They also reduce biogenic amines and the formation of heterocyclic aromatic amines (HAAs) and polycyclic aromatic hydrocarbons (PAHs). This is possible due to the presence of biologically active substances and competitive microflora from dairy products. However, some marinades, especially those that are acidic, cause a slightly acidic flavour and an unfavourable colour change. Natural compounds in the ingredients of marinades are accepted by consumers. There are no results in the literature on the impact of natural marinades on the nutritional value and health-promoting potential of meat products, so it can be assumed that this is a future direction for scientific research.

Recent developments in applications of physical fields for microbial decontamination and enhancing nutritional properties of germinated edible seeds and sprouts: a review

Germinated edible seeds and sprouts have attracted consumers because of their nutritional values and health benefits. To ensure the microbial safety of the seed and sprout, emerging processing methods involving physical fields (PFs), having the characteristics of high efficiency and environmental safety, are increasingly proposed as effective decontamination processing technologies. This review summarizes recent progress on the application of PFs to germinating edible seeds, including their impact on microbial decontamination and nutritional quality and the associated influencing mechanisms in germination. The effectiveness, application scope, and limitation of the various physical techniques, including ultrasound, microwave, radio frequency, infrared heating, irradiation, pulsed light, plasma, and high-pressure processing, are symmetrically reviewed. Good application potential for improving seed germination and sprout growth is also described for promoting the accumulation of bioactive compounds in sprouts, and subsequently enhancing the antioxidant capacity under favorable PFs processing conditions. Moreover, the challenges and future directions of PFs in the application to germinated edible seeds are finally proposed. This review also attempts to provide an in-depth understanding of the effects of PFs on microbial safety and changes in nutritional properties of germinating edible seeds and a theoretical reference for the future development of PFs in processing safe sprouted seeds.

Microbiological quality assessment of fresh produce: Potential health risk to children and urgent need for improved food safety in school feeding schemes

About 388 million school-going children worldwide benefit from school feeding schemes, which make use of fresh produce to prepare meals. Fresh produce including leafy greens and other vegetables were served at 37% and 31% of school feeding programs, respectively, in Africa. This study aimed at assessing the microbiological quality of fresh produce grown onsite or supplied to South African schools that are part of the national school feeding programs that benefit over 9 million school-going children. Coliforms, Escherichia coli, Enterobacteriaceae, and Staphylococcus aureus were enumerated from fresh produce (n = 321) samples. The occurrence of E. coli, Listeria monocytogenes, Salmonella spp., and extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae was determined. Presumptive pathogens were tested for antimicrobial resistance. E. coli was further tested for diarrheagenic virulence genes. Enterobacteriaceae on 62.5% of fresh produce samples (200/321) exceeded previous microbiological guidelines for ready-to-eat food, while 86% (276/321 samples) and 31.6% (101/321 samples) exceeded coliform and E. coli criteria, respectively. A total of 76 Enterobacteriaceae were isolated from fresh produce including E. coli (n = 43), Enterobacter spp. (n = 15), and Klebsiella spp. (n = 18). Extended-spectrum β-lactamase production was confirmed in 11 E. coli, 13 Enterobacter spp., and 17 Klebsiella spp. isolates. No diarrheagenic virulence genes were detected in E. coli isolates. However, multidrug resistance (MDR) was found in 60.5% (26/43) of the E. coli isolates, while all (100%; n = 41) of the confirmed ESBL and AmpC Enterobacteriaceae showed MDR. Our study indicates the reality of the potential health risk that contaminated fresh produce may pose to school-going children, especially with the growing food safety challenges and antimicrobial resistance crisis globally. This also shows that improved food safety approaches to prevent foodborne illness and the spread of foodborne pathogens through the food served by school feeding schemes are necessary.

Quality of rainwater and reclaimed water used in buildings and selection of appropriate indicators

OBJECTIVES

The use of alternative water sources such as rainwater or greywater (i.e., wastewater excluding water from toilets) for non-potable purposes may save water but, on the other hand, can also pose health risks to users. The main health risks come from microorganisms (such as bacteria, viruses, fungi, and protozoa). This work aims to analyse especially microbiological quality of rainwater and greywater used inside buildings in detail and to expand the existing knowledge about the potential health risks associated with these alternative water sources. It also considers methodological problems during E. coli and coliform bacteria detection. The final objective is to discuss requirements and appropriate indicators for monitoring recycled water quality.

METHODS

We examined 30 buildings with non-potable water systems in the Czech Republic and analysed a total of 137 samples of rainwater and 120 samples of greywater. From these 30 buildings, eleven, 5 of which used rainwater and 6 of which used greywater, were sampled regularly for 1-2 years for basic chemical parameters, various faecal indicators, C. perfringens, Legionella spp. and P. aeruginosa. Occasionally, samples were analysed also for the presence of environmental mycobacteria, amoebas, viruses, and selected pathogens.

RESULTS

Nearly three quarters of rainwater samples contained the faecal indicators E. coli or enterococci, or both, and in samples from several buildings also Clostridium perfringens was repeatedly detected. Untreated and treated rainwater were in respect to microbiological quality similar, suggesting that treatment processes were not very efficient. In greywater samples, beside faecal indicators, also P. aeruginosa and thermotolerant amoebas were repeatedly detected. Treatment technologies used for greywater were more efficient than those for rainwater systems.

CONCLUSION

Based on the results we evaluated appropriate indicators for monitoring recycled water quality and drafted the first Czech regulation for non-potable water.

Sous-Vide as an Alternative Method of Cooking to Improve the Quality of Meat: A Review

Sous-vide (SV) is a method of cooking previously vacuum-packed raw materials under strictly controlled conditions of time and temperature. Over the past few years, scientific articles have explored the physical, biochemical, and microbiological properties of SV cooking. In this review, we provide a critical appraisal of SV as an alternative method of meat cooking, including the types of methods, types of SV meat products, and effects of SV parameters on the meat quality and the mechanisms of transformation taking place in meat during SV cooking. Based on the available data, it can be concluded that most research on the SV method refers to poultry. The yield of the process depends on the meat type and characteristics, and decreases with increasing temperature, while time duration does not have an impact. Appropriate temperatures in this method make it possible to control the changes in products and affect their sensory quality. Vacuum conditions are given a minor role, but they are important during storage. The limited number of studies on the approximate composition of SV meat products makes it challenging to draw summarizing conclusions on this subject. The SV method allows for a higher microbiological quality of stored meat than conventional methods. The literature suggests that the SV method of preparing beef, pork, and poultry has many advantages.

Implication of Sodium Hypochlorite as a Sanitizer in Ready-to-Eat Salad Processing and Advantages of the Use of Alternative Rapid Bacterial Detection Methods

The use of disinfection agents in the washing processing of ready-to-eat (RTE) vegetables, especially sodium hypochlorite, is a common industrial practice performed to enhance microbiological quality. However, some studies have reported a restart of bacterial growth and a substantial increase in bacterial load during early storage associated with the use of disinfection agents, which might represent a risk for consumers. We evaluated the effect of sodium hypochlorite on bacterial growth trends during the shelf-life in Lactuca sativa, simulating the industrial procedures for RTE vegetable packaging. Immediately after sodium hypochlorite treatment, an effective abatement of the bacterial load was observed, followed by a restart of growth throughout storage. After 5 days, the bacterial load was close to that reached by the control samples, indicating that the net increase in bacterial load was significantly higher in the treated samples. This might be ascribed to the reduction in competitive microflora and/or to the induction of adaptive responses by resting bacteria, which might select disinfectant-resistant bacteria. These findings elicit some concerns about the actual duration of the shelf-life; products might decrease their microbiological quality earlier during storage, pointing out the need to better clarify the impact of sodium hypochlorite as a sanitizer to closer consider its use in RTE vegetable processing. Furthermore, due to the importance of the rapid estimation of bacterial load and the early detection of foodborne pathogens throughout the food chain, the accuracy of the rapid bacteria detection method, the Micro Biological Survey (MBS), and its effectiveness for microbiological analyses of RTE vegetables were evaluated.

Antimicrobial Coating Based on Tahiti Lemon Essential Oil and Green Banana Flour to Preserve the Internal Quality of Quail Eggs

This study evaluated the microbiological and internal quality of quail eggs stored for 21 days at room temperature (29.53 ± 1.36 °C) after being coated with green banana flour and Tahiti lemon essential oil (GBF/TAH). One hundred and sixty-two quail eggs were equally distributed into three treatments: (1) uncoated eggs, (2) eggs coated with green banana flour (GBF), and (3) eggs coated with GBF/TAH. The Haugh unit (HU) of the eggs was significantly lower in the third week for uncoated eggs (70.94 ± 1.63, grade A) compared to eggs coated with GBF/TAH (81.47 ± 2.38, grade AA). On the 21st day of storage, the eggs coated with GBF/TAH had significantly lower total counts of aerobic mesophilic bacteria in the shell and egg contents compared to the other treatments. GBF/TAH coating is an effective blending approach to reduce the microbial load of the shell and egg contents and preserve the sensory and internal quality of the eggs.

Influence of Storage Packaging Type on the Microbiological and Sensory Quality of Free-Range Table Eggs

The studies aimed to assess the impact of packaging, storage time, and temperature on the microbiological quality as well as on the sensory quality and functional properties of chicken eggs. The study material consisted of eggs from laying hens kept under free-range conditions. The eggs packed in cardboard and plastic cartons were stored at 5 °C and 22 °C, respectively. The eggs were examined on the day of laying and on days 14 and 28 of storage. The microbiological quality of the shell and contents of the eggs and the foaming properties of the egg white stored in cardboard and plastic packaging as well as the sensory characteristics of the eggs stored in both types of packaging after hard-boiling were examined on all evaluation dates. The type of packaging in which the eggs were stored was shown to influence the microbiological quality of the egg contents. Eggs stored in plastic packaging, on days 14 and 28 of storage, contained more bacteria in egg contents than eggs stored in cardboard packaging (p < 0.05). The type of packaging in which the eggs were stored did not have an effect on the foaming properties of the egg white (p > 0.05) or on the sensory characteristics of the eggs after hard-boiling. Irrespective of the type of packaging, the foaming properties of the egg white and the sensory characteristics of the eggs after hard-boiling deteriorated with storage time. The effect of temperature on egg quality was found. Regardless of the type of packaging, eggs stored at 5 °C after hard-boiling had better yolk colour, smell, and texture than eggs stored at 22 °C (p < 0.05).

Evaluation of packaging systems with O2-absorbers on quality of minimally processed soybean sprouts

This study evaluated the influence of O2-absorbing sachets into different packages polyethylene terephthalate (PET - E1), low density polyethylene (LDPE - E2), and PET/LDPE (E3) on the quality of minimally processed soybean sprouts (MP-sprouts). The MP-sprouts were stored up to 12 days and characterized for physicochemical, microbiological and sensory attributes. The O2-absorbing sachet showed changes during exposure to the environment by the formation of amorphous iron hydroxide, which was observed by the analysis of functional groups and XRD. The packaging used in the study showed high transmittance and clarity, and low Haze, being a good feature for storing the MP product. All packaging systems showed an increase in the volume of absorbed oxygen (cm3) up to 9 days of storage. The physic-chemical characteristics of the MP-sprouts stored for 12 days were preserved in the different packages, showing no difference regarding the use of the O2-absorbing sachet. The O2-absorbing sachet not influenced the quality of MP-sprouts during the stored (12 days). The best visual aspect was observed in PET package (with and without O2-absorbing sachet) being classified as excellent, without color change. The MP-sprouts also fulfilled the microbiological quality standards and presented 75.11% acceptability and 72.40% purchase intention.

Microbiological profiling and knowledge of food preservation technology to support guidance on a neutropenic diet for immunocompromised patients

The current society consists of an increasing number of people vulnerable to infections. For certain people with severe immunodeficiency, a neutropenic or low-microbial diet is being prescribed, which substitutes high-risk foods that are more likely to contain human (opportunistic) pathogens with lower-risk alternatives. These neutropenic dietary guidelines are typically set up from a clinical and nutritional perspective, rather than from a food processing and food preservation perspective. In this study, the current guidelines in use by the Ghent University Hospital were evaluated based on the current knowledge of food processing and preservation technologies and the scientific evidence on microbiological quality, safety, and hygiene of processed foods. Three criteria are identified to be important: (1) the microbial contamination level and composition; (2) the potential presence of established foodborne pathogens such as Salmonella spp. (to which a zero-tolerance policy is recommended); and (3) an increased vigilance for L. monocytogenes as an opportunistic foodborne pathogen with a high mortality rate in immunocompromised individuals (to which a zero-tolerance policy should apply). A combination of these three criteria was used as a framework for the evaluation of the suitability of foodstuffs to be included in a low-microbial diet. Differences in processing technologies, initial contamination of products, etc., however, lead to a high degree of variability in microbial contamination and make it difficult to unambiguously accept or reject a certain type of foodstuff without prior knowledge of the ingredients and the processing and preservation technologies applied during manufacturing and subsequent storage conditions. A restricted screening on a selection of (minimally processed) plant-based foodstuffs on the retail market in Flanders, Belgium supported decision-making on the inclusion of these food types in a low-microbial diet. Still, when determining the suitability of a foodstuff to be included in a low-microbial diet, not only the microbiological status but also nutritional and sensorial properties should be assessed, which requires multidisciplinary communication and collaboration.

Quality Attributes of Cold-Stored Khalal Barhi Dates Treated with Guava Leaf Extract and/or Lactic Acid as Natural Preservatives

The use of natural ingredients to preserve the quality of fresh fruits is a promising approach to healthier products and a more sustainable industry. The present study was carried out to assess the effect of lactic acid (LA) and guava leaf extract (GLE) as natural preservatives on the quality parameters of Khalal Barhi dates. Physicochemical properties, antioxidant activity, color parameters, firmness, sensory properties, and yeast and mold counts of date fruits were evaluated during five weeks of storage at 4 ± 1 °C. The bioactive compounds in GLE were estimated by HPLC, which exhibited that GLE contains significant amounts of bioactive compounds, mainly, phenolics and flavonoids. With prolonged storage, the moisture content decreased, while the total soluble solids (TSS) increased in all samples. Similarly, a slight decrease in the pH with a concomitant increase in titratable acidity (TA) was observed throughout the storage. Generally, the samples treated with natural preservatives revealed lower changes in moisture content, TSS, pH, and TA than the control. The results exhibited decreased total phenolic content (TPC) and antioxidant activity for all samples with extended storage. The GLE and LA + GLE treatments significantly (p < 0.05) increased TPC and antioxidant activity on day 0 and preserved higher values of both during storage. Additionally, a decrease in the L* and b* values with an increase in the a* values of all samples was observed with advancement of storage. The LA + GLE treatment minimized the changes in color parameters and maintained higher firmness values during storage. Similarly, the sensory properties of all samples decreased with prolonged storage, but insignificant (p > 0.05) differences were found among the samples. Dipping treatments inhibited microbial growth over time, with the lowest yeast and mold counts achieved by the LA + GLE treatment. It can be concluded that the LA + GLE treatment has a protective effect on Khalal Barhi dates by minimizing post-harvest changes and decreasing the microbial load.

Impact of the Addition of Tenebrio molitor and Hermetia illucens on the Physicochemical and Sensory Quality of Cooked Meat Products

The use of proteins from insects, plants, microalgae, fungi or bacteria as an alternative to proteins of animal origin such as meat, fish, eggs or milk can meet the worldwide protein demand in the future. As the consumption of whole insects might be problematic or unacceptable for many consumers, especially in European countries, the use of homogenized insects or protein extracts from insects for the production of products might be a possibility to overcome general acceptability problems. However, the quality criteria of these products have to be comparable with consumers' expectations with regard to known products. Therefore, in the present study, we produced a meat product, replaced 10% and 20% of the pork with homogenized larvae of Tenebrio molitor and Hermetia illucens, and determined different physicochemical and sensory parameters at production and during modified atmosphere storage for 21 days. Additionally, the alteration of different bacteria species during this storage was analyzed in challenge tests. After production, the addition of insects resulted in higher cooking losses and pH values in the products with 20% insects, higher pH and yellowness, lower lightness, protein and hardness results in the Hermetia products, as well as higher yellowness and lower protein and hardness values in the cooked meat products with Tenebrio molitor. During modified atmosphere storage, the color differences principally remained, whereas the concentrations of inoculated Bacillus cereus, Listeria monocytogenes and Escherichia coli were not influenced by the addition of insects to the cooked meat products. The sensory results of the insect products, especially at higher concentrations and with Hermetia illucens, worsened during modified atmosphere storage. The addition of homogenized insect larvae, especially at higher concentrations and particularly of Hermetia illucens, influences different physicochemical and sensory parameters of the cooked meat products.

Effect of myrtle leaves integration in sheep diet and its addition as powder on leg meat' oxidative stability, physicochemical, microbiological and sensory properties during storage

The synthetic antioxidant improved the shelf life of meat products; however, consumers start to reject them for health reason. For this, the natural antioxidants like Myrtle distillate leaves (MDL) could be an interesting alternative and potential natural antioxidant given their richness in bioactive compounds. This study aimed to test the effect of myrtle distillate leaves (MDL) as natural antioxidant in premortem phase as diet of cull ewes and in postmortem phase in form of powder added to deboned legs on meat' quality. All ewes received individually 500 g of hay and 750 g of concentrate for Control (C) group; for Myrt group, the concentrate was partially replaced (400 g) by pellets containing 30% MDL and 350 g concentrate. For each ewe, both legs were used for the experiment; one leg was treated with MDL powder and the other with Control. Meat from ewes' fed MDL presented better scores for red color, aftertaste and juiciness, than control group. Meat treated with MDL powder showed the highest values of total phenolic, α-tocopherol content and redness score with lower lipid oxidation (p < .05). The microbiological quality of meat was not affected by MDL. Myrtle distillate leaves could be used in different forms, in order to obtain higher meat product quality.

Quality and Microbiological Safety of Poultry Meat Marinated with the Use of Apple and Lemon Juice

The aim of the study was to evaluate the use of apple juice for the marinating of poultry meat and its effect on the technological as well as sensory characteristics and microbiological safety of the raw product after heat treatment. Broiler chicken breast muscles were marinated for 12 h in apple juice (n = 30), a mixture of apple and lemon juice (n = 30) and compared with those in lemon juice (n = 30). The control group (n = 30) consisted of unmarinated breast muscles. Following the evaluation of the technological parameters (pH, L*, a*, b* colour, cutting force, cooking losses) quantitative and qualitative microbiological evaluations were performed on the raw and roasted products. The microbiological parameters were determined as total Mesophilic aerobic microorganisms, Enterobacteriaceae family, and Pseudomonas count. The bacterial identification was performed using a matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. The marinating resulted in lower pH value, but increased tenderness of raw and roasted products. Marinating chicken meat in both apple and lemon juices, including their mixtures and in the control sample, resulted in increased yellow saturation (b*). The highest flavour desirability and overall desirability were obtained in products marinated using a mixture of apple and lemon juice, while the most desirable aroma was obtained from products marinated with apple juice. A significant antimicrobial effect was observed in marinated meat products compared to unmarinated, irrespective of the type of marinade used. The lowest microbial reduction was observed in the roasted products. Apple juice can be used as a meat marinade because it promotes interesting sensory properties and improves the microbiological stability of poultry meat while maintaining the product's good technological characteristics. It makes a good combination with the addition of lemon juice.

Effect of Chitosan and Alginate-Based Edible Membranes with Oregano Essential Oil and Olive Oil in the Microbiological, Physicochemical and Organoleptic Characteristics of Mutton

Edible chitosan or alginate coatings and their combinations with oregano essential oil or olive oil, have been examined for their effect on the microbiological, physicochemical and organoleptic characteristics of mutton. The results indicated that these edible coatings can contribute to maintaining good quality characteristics and extending mutton shelf-life. The total mesophilic counts in mutton ranged from 3.48 to 8.00 log¹⁰ CFU/g, the total psychrophilic counts from 4.00 to 9.50 log¹⁰ CFU/g, the B. thermosphacta counts from 2.30 to 7.77 log¹⁰ CFU/g and the lactic acid bacteria counts from 2.00 to 5.85 log¹⁰ CFU/g. Chitosan coatings significantly (p < 0.05) reduced the total mesophilic, the total psychrophilic (1-2 log₁₀ cfu/g), the B. thermosphacta and the lactic acid bacteria counts in mutton. Alginate exhibited a lower L* value and a higher a* value and chroma compared with the control and chitosan lots. No significant differences were observed in the chemical composition of meat pieces among the experimental groups. Oregano oil positively affected the sensory attributes of meat. The most favourable combination, based on the microbiological counts, the organoleptic characteristics and the shelf-life extension of mutton, was that of chitosan with oregano essential oil.

Design and Characterization of a Cheese Spread Incorporating Osmundea pinnatifida Extract

Marine algae have been emerging as natural sources of bioactive compounds, such as soluble dietary fibers and peptides, presenting special interest as ingredients for functional foods. This study developed a cheese spread incorporating red seaweed Osmundea pinnatifida extract and subsequently characterized it in terms of nutritional, pH, and microbiological parameters and bioactivities including prebiotic, antidiabetic, antihypertensive, and antioxidant activities. This food was produced through incorporation of O. pinnatifida extract (3%), obtained via enzymatic extraction Viscozyme L in a matrix containing whey cheese (75%) and Greek-type yoghurt (22%). The product was then subjected to thermal processing and subsequently stored for 21 days at 4 °C. During storage, this food showed a high pH stability (variations lower than 0.2 units), the absence of microbial contamination and all tested bioactivities at the sampling timepoints 0 and 21 days. Indeed, it exerted prebiotic effects under Lactobacillus acidophilus LA-5^® and Bifidobacterium animalis subsp. lactis BB-12^®, increasing their viability to around 4 and 0.5 log CFU/g, respectively. In addition, it displayed antidiabetic (α-glucosidase inhibition: 5-9%), antihypertensive (ACE inhibition: 50-57%), and antioxidant (ABTS: 13-15%; DPPH: 3-5%; hydroxyl radical: 60-76%) activities. In summary, the cheese spread produced may be considered an innovative food with high potential to contribute toward healthier status and well-being of populations.

Microbiological Quality of Raw Donkey Milk from Serbia and Its Antibacterial Properties at Pre-Cooling Temperature

The aim of this study was to examine the microbiological quality of raw donkey milk of an indigenous Serbian breed as well as the changes in the microbial populations during storage at 4 °C. In addition, antibacterial activity of donkey milk against E. coli, L. monocytogenes and S. aureus at 15 °C as well as the content of the two main antibacterial proteins lysozyme and lactoferrin were investigated. Microbiological examination of 137 individual milk samples collected over a period of 21 months showed good microbiological quality since foodborne pathogens such as Salmonella spp. and L. monocytogenes were not detected in any of the analyzed samples, while the number of E. coli, Enterobacteriaceae, total coliform bacteria, sulfite-reducing Clostridia and aerobic sporogenic bacteria was below the limit of quantification (<1 cfu mL^-1). During the six-days storage at 4 °C, total bacterial counts and the counts of lactic acid bacteria remained at the initial level while pathogenic bacteria were not detected. The strongest antibacterial activity of the tested milk was observed against E. coli, while S. aureus was the least sensitive to milk antibacterial compounds. Although further research is needed to fully elucidate the antibacterial mechanism and synergistic activity of different compounds in donkey milk, the high content lysozyme (2.63 ± 0.03 g L^-1) and lactoferrin (15.48 mg L^-1) observed in tested milk could contribute to its strong antibacterial activity and extension of the storage period during which it can be safely consumed.

Minimally processed fruits as vehicles for foodborne pathogens

The consumption of minimally processed fruit (MPF) has increased over the last decade due to a novel trend in the food market along with the raising consumers demand for fresh, organic, convenient foods and the search for healthier lifestyles. Although represented by one of the most expanded sectors in recent years, the microbiological safety of MPF and its role as an emergent foodborne vehicle has caused great concern to the food industry and public health authorities. Such food products may expose consumers to a risk of foodborne infection as they are not subjected to prior microbial lethal methods to ensure the removal or destruction of pathogens before consumption. A considerable number of foodborne disease cases linked to MPF have been reported and pathogenic strains of Salmonella enterica, Escherichia coli, Listeria monocytogenes, as well as Norovirus accounted for the majority of cases. Microbial spoilage is also an issue of concern as it may result in huge economic losses among the various stakeholders involved in the manufacturing and commercialization of MPF. Contamination can take place at any step of production/manufacturing and identifying the nature and sources of microbial growth in the farm-to-fork chain is crucial to ensure appropriate handling practices for producers, retailers, and consumers. This review aims to summarize information about the microbiological hazards associated with the consumption of MPF and also highlight the importance of establishing effective control measures and developing coordinated strategies in order to enhance their safety.

Impact of packaging system on the microbial quality of chilled rabbit meat over 21 days of storage

The pace of life is accelerating, so we are seeking ways to optimize the shelf life of products. To achieve this goal, the microbiological quality of rabbit meat was assessed at 7, 14, and 21 days under refrigerated conditions, utilizing two storage methods, modified atmosphere packaging (MAP) and vacuum packaging (VAC). Maintaining high levels of hygiene is critical not only during slaughter but also during subsequent technological processes and meat storage. The research concluded that the MAP method was more effective at extending the shelf-life of fresh rabbit meat than the VAC method. Additionally, increasing the CO₂ concentrations in meat significantly decreased the Pseudomonas bacteria population (after 14 and 21 days of storage). Conversely, the gaseous mixture containing 70% O₂ significantly decreased the Enterobacteriaceae population in the sample after 21 days of storage. Moreover, the MAP storage method considerably impeded microbial growth, particularly the total yeast and mold count, lactic acid bacteria count, and Pseudomonas spp. count. This study's findings demonstrate that rabbit meat can be stored for 21 days in a modified atmosphere containing appropriate concentrations of gases such as gaseous carbon dioxide and oxygen.

Microbiological Safety of Cut Melons Sold in Portuguese Retail Markets: A Pilot Study

Due to the increasing consciousness of a healthy diet and pursuit of convenience among consumers, the market for fresh fruit is on the rise, and the melon is among the most welcome of fruits for its sensory attributes and nutritional properties. Consumption safety of cut fruit remains an issue of concern that may affect public health. This study aimed to perform the microbiological characterisation of a melon, Cucumis melo L. var. “Piel de Sapo”, cut by retailers, wrapped in plastic cling film and kept at room temperature in local fruit shops. In addition, the possible transfer of relevant foodborne pathogens, during slicing, from the peel to the interior of the melon, and bacterial growth, were also evaluated when the melon slices were stored at abusive temperatures for 2 days. In this pilot study, a low number of samples were characterised microbiologically (26 cut melons), and some isolates were identified by 16S rRNA sequencing. No Listeria spp. or Salmonella spp. were detected in any of the samples, while Escherichia coli and Staphylococcus aureus were present in four and six out of twenty-six samples, respectively. Following artificial contamination of melons with cocktails of Salmonella spp., E. coli and Listeria monocytogenes, it was observed that, despite the smaller number of L. monocytogenes recovered, all the pathogens were transferred from the contaminated peels to the interior of the melons. Furthermore, over storage time, significant differences were observed (p < 0.05) between the counts obtained from melon slices immediately after cutting (0 h), and after 24 and 48 h at 20 °C, with an increase of about 4 log CFU/g in all the pathogens. In conclusion, some cut melons classified as microbiologically unacceptable or unsatisfactory are being sold in local fruit shops in the Porto Metropolitan Area, Portugal. Although absent in the samples analysed, Salmonella spp. and L. monocytogenes, if present, can be transferred from the outside to the inside of the fruit by the cutting blade and, if not consumed immediately and stored at abusive temperatures, this ready-to-eat product poses a risk of infection. This pilot study, performed for the first time in Portugal under these conditions, clearly demonstrates the need for education campaigns to alert local sellers and consumers of the risk posed by cut melons.

High-Intensity Ultrasound Processing Enhances the Bioactive Compounds, Antioxidant Capacity and Microbiological Quality of Melon (Cucumis melo) Juice

The bioactive compounds, antioxidant capacity and microbiological quality of melon juice processed by high-intensity ultrasound (HIUS) were studied. Melon juice was processed at two ultrasound intensities (27 and 52 W/cm2) for two different processing times (10 and 30 min) using two duty cycles (30 and 75%). Unprocessed juice was taken as a control. Total carotenoids and total phenolic compounds (TPC) were the bioactive compounds analyzed while the antioxidant capacity was determined by DPPH, ABTS and FRAP assays. The microbiological quality was tested by counting the aerobic and coliforms count as well as molds and yeasts. Total carotenoids increased by up to 42% while TPC decreased by 33% as a consequence of HIUS processing regarding control juice (carotenoids: 23 μg/g, TPC: 1.1 mg GAE/g), gallic acid and syringic acid being the only phenolic compounds identified. The antioxidant capacity of melon juice was enhanced by HIUS, achieving values of 45% and 20% of DPPH and ABTS inhibition, respectively, while >120 mg TE/100 g was determined by FRAP assay. Further, the microbial load of melon juice was significantly reduced by HIUS processing, coliforms and molds being the most sensitive. Thus, the HIUS could be an excellent alternative supportive the deep-processing of melon products.

Bacteriological Quality and Public Health Risk of Ready-to-Eat Foods in Developing Countries: Systematic Review and Meta Analysis

Background:

Ready-to-eat foods are foods that are consumed at the point of sale or later, without any further processing or treatment. Foodborne diseases are on the rise worldwide, involving a wide range of diseases caused by pathogenic bacteria, and are becoming a public health problem. Therefore, this study sought to identify and determine the bacteriological quality and public health risks in ready-to-eat foods in developing countries.

Methods:

The studies published from 2012 to 2020 were identified through systematic searches of various electronic databases such as Google Scholar, PubMed and MEDLINE, MedNar, EMBASE, CINAHL, Scopus, and Science Direct. The articles were searched using a Boolean logic operator (“AND,” “OR,” “NOT”) combination with Medical Subject Headings (MeSH) terms and keywords. All identified keywords and an index term were checked in all included databases. In addition, a quality assessment is performed to determine the relevance of the article, and then the data are extracted and analyzed.

Results:

The current study found that the pooled prevalence of Staphylococcus aureus, Enterobacter species, Klebsiella, Escherichia coli, Salmonella, Bacillus cereus, Pseudomonas species, and Shigella in ready-to-eat foods was 30.24% (95% CI: 18.8, 44.65), 11.3% (95% CI: 6.6, 18.7), 9.1% (95% CI: 7.0, 11.8), 23.8% (95% CI: 17.5, 31.5), 17.4% (95% CI: 11.6, 25.31)], 26.8% (95% CI: 13.7, 45.9), 6.1% (95% CI: 2.8, 12.6), 34.4% (95% CI: 18.1-55.4), respectively.

Conclusions:

Most of the reviewed articles reported on various pathogenic bacterial species that are potentially harmful to human health, such as Staphylococcus aureus, Salmonella, Shigella, and Escherichia coli in ready-to-eat food above the maximum allowable limit. Therefore, relevant national and international organizations must take corrective measures to prevent foodborne diseases and protect human health.

Black Soldier Fly Larvae Meal in the Diet of Gilthead Sea Bream: Effect on Chemical and Microbiological Quality of Filets

The chemical and microbiological characteristics of filets of Spaurus aurata L. specimens fed with diets containing a Hermetia illucens meal (HIM) at the 25, 35, and 50%, as a partial replacement for fish meal (FM) were evaluated. The diets, formulated to satisfy the nutritional needs of fish, were isoenergetic (22 MJ/kg gross energy), isonitrogenous (43 g/100 g, a.f.), and isolipidic (19 g/100 g, a.f.). Seventy-two specimens were randomly killed after 186 days of growing trials. Then, the filets were analyzed for chemical profile, fatty acids, amino acids, minerals, and microbial flora. Data were subjected to statistical analysis. No significant differences were observed in chemical composition. The sum of polyunsaturated fatty acids (PUFAs) showed a similar content in the filets; eicosapentaenoic acid was similar in the filets of HIM0, HIM35%, and HIM50%, whereas docosahexaenoic acid was higher in filets of the HIM0 group. n3/n6 PUFA ratio and the sum of EPA + DHA showed a high value (p < 0.001) in filets of the group fed with FM. No significant difference was observed in thrombogenic index and hypocholesterolaemic/hypercholesterolaemic ratio in the groups; the atherogenic index showed a higher value (p = 0.001) in the HIM50% group. Indispensable amino acids showed some significant (p < 0.0001) differences in the groups; arginine and phenylalanine content was higher in the filets of fish fed with FM; isoleucine and valine content was higher in the filets of HIM50%; leucine, lysine and methionine content was lower in the filets of HIM35%; histidine content was lower in the filets of HIM25%; tryptophan content was lower in filets of the HIM50% group. EAA/NEAA ratio showed highest value in the filets of the group that received FM. The presence of HIM in the three diets kept chromium, manganese, iron, copper, zinc, and nickel levels lower than those recommended by various authorities. Ca/P ratio showed a higher level (p < 0.0001) in the group fed with FM than those fed with diets containing HIM. The insect meal in the diets did not influence the microbiological profile of fish. Use of HIM as an unconventional feed ingredient in Sparus aurata diet looks promising, although the quality of filets may be affected.

Impact of Freezing on the Microbiological Quality and Physical Characteristics of Buffalo Mozzarella Cheese

Simple Summary

Buffalo Mozzarella cheese from Campania is made from the fresh milk of the Italian Mediterranean buffalo. In 1996, thanks to its distinctive characteristics (specific environmental conditions and production method), Regulation (EC) No. 1107/96 recognized it as a Protected Designation of Origin product. The limited availability of milk and the increased demand for buffalo mozzarella cheese, especially during the spring-summer period (when milk production is lowest), have induced the use of frozen milk or curd for its production. The aim of this research was to provide preliminary results about the effect of freezing on microbial communities of fresh buffalo milk, curd and Buffalo Mozzarella cheese, and on physical properties (whiteness, hardness, and oxidation state) of Buffalo Mozzarella cheese. The preliminary results obtained have allowed us to conclude that the freezing process if properly carried out, does not compromise the microbiological quality of the products but produces only slight changes of some physical properties.

Abstract

Buffalo Mozzarella cheese from Campania is one of the most worldwide appreciated Italian dairy products. The increased demand for buffalo dairy products and the limited availability of the finest buffalo milk has prompted the diffusion of illicit practices, such as the use of milk, curd, or other products that are frozen or bought at low cost. The aim of this research was to provide preliminary results about the trend of the microbial communities of buffalo milk, curd and Buffalo Mozzarella cheese, during freezing storage of eleven months. At the same time, the alterations of physical properties and the presence of the molecular marker “γ4-casein”, have been investigated. The results showed that freezing reduced the concentrations of the total bacterial count, Enterobacteriaceae, coliforms, Escherichia coli and yeasts in fresh milk and, the concentrations of the total bacterial count, coliforms, lactic acid bacteria and yeasts in mature curd. In the finished product, no notable decreases were observed, except for lactic acid bacteria. About the γ4-casein, no increase was observed in all matrices. These preliminary results allow us to conclude that the freezing process if properly carried out, does not compromise the microbiological quality and the physical properties of the Buffalo Mozzarella cheese.

Research Note: Antimicrobial resistance profile of Enterococcus spp. isolated from the eggshell of laying hens submitted to pharmacological treatment

The occurrence of antimicrobial resistance in microorganisms isolated from eggshells, especially Enterococcus, might serve as a parameter to assess the selection of bacteria due to the use of drugs in the diet of laying hens. In order to evaluate the frequency and the antimicrobial resistance profile of Enterococcus spp. isolated from the eggshells, 225 Hy-line laying hens were submitted to a 25-d long trial. The treatments were the following: hens fed ration without antimicrobials (control) and groups that received oxytetracycline (10 mg kg⁻¹), doxycycline (20 mg kg⁻¹), lincomycin (50 mg kg⁻¹), and enrofloxacin (10 mg kg⁻¹) in the ration for 5 d. Six replications were analyzed per treatment, composed of a pool of 5 eggs each. They were collected before treatment and on days 3, 6, 15, and 25, totaling 150 samples. Eggshells were submitted to counts of Enterococcus spp., which were identified by proteomic analyses. Antimicrobial resistance was determined by the disk-diffusion test. It was observed that 97.3% (n = 146) of the samples were contaminated with Enterococcus spp. There were no differences (P > 0.05) in the bacterial counts between treatments on the same day of evaluation. E. faecalis and E. faecium were the most frequent on the eggshells of all treatments. Multiresistance to the four classes of antimicrobials was also verified in the isolated bacteria. A total of 83% of the Enterococcus isolates showed resistance to neomycin, which was not administered to the hens, demonstrating an environmental problem. Thus, feeding laying hens with diets added with antimicrobials induces drug resistance in Enterococcus spp., isolated form the eggshells.

Technological and Sensory Quality and Microbiological Safety of RIR Chicken Breast Meat Marinated with Fermented Milk Products

Simple Summary

The use of meat from hens after the end of the laying period is limited due to their inferior sensory properties compared to the meat of young slaughter birds, mainly due to the age of the hens. Therefore, we are looking for effective methods of softening the meat of laying hens after the end of the annual laying use. One way to reduce the hardness of hen meat after the laying period is to marinate it with fermented milk products. The aim of the research was to evaluate the effect of marinating with buttermilk and sour milk on the quality of Rhode Island Red (RIR) hen meat after the first year of laying use. In the conducted research, it was found that marinating hen meat after the first year of laying with fermented milk products has a beneficial effect on the characteristics of raw and roasted meat. Roasted hen meat was characterised by a brighter colour, lower hardness, and better microbiological quality, and had greater overall acceptability. The obtained results allow us to conclude that marinating hen meat with fermented milk products creates new opportunities and prospects for the culinary use of the meat of RIR hens after one year of laying use.

Abstract

The aim of the study was to determine the effect of marinating with fermented milk products (buttermilk and sour milk) on the physical characteristics, microbiological quality, and sensory acceptability of Rhode Island Red (RIR) hen meat after the first year of laying use. The hen breast meat was marinated with fermented dairy products, buttermilk and sour milk, by the immersion method for 12 h at 4 °C. The assessed features included the quality of raw and roasted marinated and non-marinated meat in terms of physical characteristics (marinade absorption, water absorption, pH, L*, a*, b* colour, shear strength, texture profile analysis (TPA) test), microbiological parameters, and sensory characteristics. Bacteria were identified by the mass spectrometry method (MALDI-TOF MS Biotyper). Marinating meat with fermented dairy products lightened the colour, decreased the value of shear force, reduced hardness and chewiness, and limited the growth of aerobic bacteria and Pseudomonas spp. Additionally, after heat treatment, the number of identified aerobic bacteria families in the marinated in buttermilk and marinated in sour milk groups was smaller than in the non-marinated muscle group. The sensory evaluation showed a beneficial effect of marinating with buttermilk and sour milk on the tenderness, juiciness, and colour of roasted meat.

Development and validation of a one-step modelling approach for the determination of chicken meat shelf-life based on the growth kinetics of Pseudomonas spp

The main objective of the present study was to investigate the effect of storage temperature on aerobically stored chicken meat spoilage using the two-step and one-step modelling approaches involving different primary models namely the modified Gompertz, logistic, Baranyi and Huang models. For this purpose, growth data points of Pseudomonas spp. were collected from published studies conducted in aerobically stored chicken meat product. Temperature-dependent kinetic parameters (maximum specific growth rate 'µ_max' and lag phase duration 'λ') were described as a function of storage temperature through the Ratkowsky model based on the different primary models. Then, the fitting capability of both modelling approaches was compared taking into account root mean square error, adjusted coefficient of determination (adjusted-R²) and corrected Akaike information criterion. The one-step modelling approach showed considerably improved fitting capability regardless of the used primary model. Finally, models developed from the one-step modelling approach were validated for the maximum growth rate data extracted from independent published literature using the statistical indexes Bias (B_f) and Accuracy (A_f) factors. The best prediction capability was obtained for the Baranyi model with B_f and A_f being very close to 1. The shelf-life of chicken meat as a function of storage temperature was predicted using both modelling approaches for the Baranyi model.

Tejuino, a Traditional Fermented Beverage: Composition, Safety Quality, and Microbial Identification

This study aims to analyze the chemical and microbial composition and characterize volatile compounds from the artisanal and commercial Tejuino beverage. For this, eight samples are analyzed (four artisanal and four commercial). The chemical and microbiological quality is determined by standard methods, and volatile compounds are determined by solid-phase microextraction. Overall, the physicochemical composition and microbiological quality are higher for artisanal Tejuino (p < 0.05). The pH values were 3.20 and 3.62, and 0.76 and 0.46 meq of lactic acid for artisanal and commercial Tejuino, respectively. With volatile compounds analyzed, esters, benzenes, and aldehydes were predominant; meanwhile, ethanol was a volatile compound with the highest concentration for all samples. Saccharomyces cerevisiae and Limosilactobacillus fermentum were identified in artisanal Tejuino; yeasts of the Pichia genera and Lactiplantibacillus plantarum, for commercial Tejuino, and Enterococcus genus were identified in both samples. The characterization of both types of Tejuino allows us to update the information available on this important Mexican beverage. In addition, the isolation of lactic acid bacteria, as representative bacteria of both drinks, offers an area of opportunity to know the potential functionality of these bacteria in traditional fermented products.

Effects of Peppermint Extract and Chitosan-Based Edible Coating on Storage Quality of Common Carp (Cyprinus carpio) Fillets

Edible coatings have recently been developed and applied to different food matrices, due to their numerous benefits, such as increasing the shelf life of foods, improving their appearance, being vehicles of different compounds, such as extracts or oils of various spices that have antioxidant and antimicrobial activity, as well as being friendly to the environment. The objective of this research was to develop a new edible coating based on chitosan enriched with peppermint extract and to evaluate its effectiveness to inhibit microbial development in vitro and improve both the quality and shelf life of common carp (Cyprinus carpio) during refrigerated storage (4 ± 1 °C). Three treatments were used: edible coating (C + EC), edible coating +, 5% chitosan (C + ECCh) and edible coating + 1.5% chitosan + 10% peppermint (C + ECChP). Prior the coating carp fillets; the antibacterial activity and antioxidant capacity were evaluated in the peppermint extract and coating solutions. After coating and during storage, the following were determined on the fillet samples: microbiological properties, observed for ECP, an inhibition halo of 14.3 mm for Staphylococcus aureus, not being the case for Gram-negative species, for ECCh, inhibition halos of 17.6 mm, 17.1 mm and 16.5 mm for S. aureus, Salmonella typhimurium and Escherichia coli, respectively; for the ECChP, inhibition halos for S. aureus, S. typhimurium and E. coli of 20 mm, 17 mm and 16.8 mm, respectively. For the physicochemical characteristics: an increase in solubility was observed for all treatments during storage, reaching 46.7 mg SN protein/mg total protein for the control, and values below 29.1 mg SN protein/mg total protein (p < 0.05), for fillets with EC (C + EC > C + ECCh > C + ECChP, respectively at the end of storage. For the pH, maximum values were obtained for the control of 6.4, while for the fillets with EC a maximum of 5.8. For TVB-N, the fillets with different CE treatments obtained values (p < 0.05) of 33.3; 27.2; 25.3 and 23.3 mg N/100 g (control > C + E C > C + ECCh > C + ECChP respectively). Total phenolic compounds in the aqueous peppermint extract were 505.55 mg GAE/100 g dried leaves, with 98.78% antioxidant capacity in the aqueous extract and 81.88% in the EC. Biomolecule oxidation (hydroperoxide content) had a significant increase (p < 0.05) in all treatments during storage, 1.7 mM CHP/mg protein in the control, to 1.4 in C + EC, 1.27 in C + ECCh and 1.16 in C + ECChP; TBARS assay values increased in the different treatments during refrigerated storage, with final values of 33.44, 31.88, 29.40 and 29.21 mM MDA/mg protein in the control; C + EC; C + ECCh and C + ECChP respectively. In SDS -PAGE a protective effect was observed in the myofibrillar proteins of fillets with ECChP). The results indicate that the C + ECCh and C + ECChP treatments extend the shelf life of 3–5 days with respect to microbiological properties and 4–5 days with respect to physicochemical characteristics. A reduction in lipid and protein oxidation products was also observed during refrigerated storage. With these findings, this is considered a promising method to increase the shelf life of fish fillets combined with refrigeration and we are able to recommend this technology for the fish processing industry.

Application of PET/Sepiolite Nanocomposite Trays to Improve Food Quality

New PET and nanosepiolite materials are produced for its application in innovative packaging with better performance. In our previous work, we demonstrate that the use of different percentages of sepiolite modified with different organosilanes improved mechanical and barrier properties of PET. Nanocomposites permeability can decrease up to 30% compared to that of pure PET and the mechanical analyses show that, although PET nanocomposites are more brittle than virgin PET, they are also harder. In the present work, we are going to study the properties of this innovative packaging with real food analyzing mechanical properties related to the product transport together with permeability and microbiological characteristics. At the same time, it has been seen that it is possible to lighten trays, which is very important both industrially and environmentally. On the other hand, a good quality packaging for food needs to ensure that organoleptic and physico-chemical characteristics of the product inside are not modified due to migration of any of the packaging material to the food itself. Results obtained in this work also show lower count of aerobic mesophilic bacteria and Enterobacteriaceae (EB), reducing the incidence of food contaminations by microorganisms.

Effect of Delayed Refrigeration on the Microbial Carcass Contamination of Wild Boars (Sus scrofa)

Simple Summary

The bacteria that contaminate meat after the death of the animal can come from multiple sources, such as the animal itself, the external environment and the operator who handles it. The prompt refrigeration of hunted game is generally considered an important step to prevent spoilage and meat alterations, although many logistic hindrances, such as animal weight and distance from the hunting area to the refrigerators, limit the meticulous adoption of the best procedures. We show that the bacterial population of wild boar carcasses is not correlated to the mere time from shot to refrigeration but is correlated to the refrigeration time from chilling to analysis. The results of our study revealed a correlation between the time from shot to analysis and from refrigeration to analysis but a lack of correlation between the time from shot to refrigeration.

Abstract

The immediate refrigeration of meat after slaughter is a key issue for the proper storage and aging of meat. The industry standard cold chain relies on low temperatures and ventilation to lower the internal carcass temperature to 0–4 °C within the first 48 h, i.e., within four times the so-called semi-cooling time. On the other hand, for games, once bled and eviscerated, the carcass must be sent to a point where it can be sectioned or kept on air for maturation at refrigeration temperature. The precautions to observe are few and simple but essential: protect the meat and start the cooling process quickly. After preparing the animal (bleeding and evisceration), it may be necessary to face a period of transport that is sometimes long and not very easy; while small animals can be easily transported in a backpack, larger ones must necessarily be carried by several people or sometimes dragged to the vehicle capable of transporting them. It is obvious that a wild boar opened from the jaws to the pelvis and dragged for hundreds of meters will tend to be contaminated, although these contaminations are to be considered secondary for the preservation of the meat, compared to contamination by the intestinal contents. In an attempt to investigate the effect of delayed refrigeration on wild boar carcass contamination, the aim of this work was to determine a correlation between several hunting and logistic parameters (age, sex, animal weight, shooting distance, number of shots, weather and temperature and time from shot to refrigeration and to analysis) and bacterial contamination of the carcass. The correlation coefficient, r, was found to be 0.038 for the eviscerated body weight (p < 0.05), 0.091 for the external temperature on the day of hunting (p < 0.05), 0.027 for the time from shot to refrigeration (p = 0.081), 0.038 for the time from refrigeration to analysis (p < 0.05) and 0.043 for the time from shot to analysis (p < 0.05). These results stand for a negative correlation between the bacterial population and eviscerated carcass weight and between the bacterial population and external temperature and for a positive correlation between the time from shot to analysis and from refrigeration to analysis. No association was demonstrated between the bacterial population and the time from shot to refrigeration.

Cluster Analysis Classification of Honey from Two Different Climatic Zones Based on Selected Physicochemical and of Microbiological Parameters

The geographical origin of honey affects its composition, which is of key importance for the health-promoting properties and safety of the product. European regulations clearly define the physicochemical requirements for honey that determine the microbiological quality. On the other hand, legislation abolishes microbiological criteria. In the study 40 honey samples originating from two different climatic zones were analyzed. The water content, pH, water activity analysis and the microbiological quality of honey samples have been tested using the reference plate method (total viable count, yeast and molds, lactic acid bacteria, Bacillus spp.). The cluster classification showed that total viable count of bacteria could be used as a measure alternative to the count of Bacillus spp. and 70% of honeys from the tropical climate zone had different microbiological quality than honeys from the temperate climate zone but still under the level 3.0 log cfu/g. The study has revealed that geographical origin of honey may significantly affect the quality and safety of honey. It was considered that water content can be the most informative and handy marker of the microbiological quality of honeys. Analysis of lactic acid bacteria showed temperate climate zone honeys as a source of beneficial bacteria in the diet.

Functional and Quality Characteristics of Ginger, Pineapple, and Turmeric Juice Mix as Influenced by Blend Variations

In this current work, the functional and quality characteristics of ginger, pineapple, and turmeric juice mix as influenced by blend variations were investigated. Specifically, the blends had constant ginger amounts, decreased pineapple, and increased turmeric proportionally. Additionally, the functional properties involved physicochemical (pH, soluble solids (SS), total titratable acidity (TA) and viscosity), proximate (moisture, protein, fat and ash), minerals (Ca, and Mg) and vitamin C and β-carotene analyses, whereas quality properties involved microbiological and sensory analyses. The results showed that as quantities of pineapple and turmeric respectively decreased and increased, there was significant increases in Ca, Mg, vitamin C, and β-carotene contents (p < 0.05). Across the blends, the degree of significant differences (p < 0.05) in the protein, fat, and ash seemed more compared to those of moisture contents. Despite the increases in pH and viscosity, and decreases in SS and TA, the increases in turmeric potentially reinforced by ginger most likely decreased the bacterial/fungi counts, as well as inhibition zones. Increasing and decreasing the respective amounts of turmeric and pineapple might not necessarily make the blends more acceptable, given the decreases in appearance, taste, aroma, and mouthfeel scores.

Effects of Whey Protein Isolate-Based Film Incorporated with Tarragon Essential Oil on the Quality and Shelf-Life of Refrigerated Brook Trout

The efficiency of some films prepared from heat-denatured whey protein isolate solutions on the quality and shelf-life of brook trout samples during storage at 4 °C was studied in this research (WPIf-a film based on whey protein isolate and WPIf+2.5%TEO-a film based on whey protein isolate incorporated with 2.5% tarragon essential oil). The control and covered fish samples were periodically assessed (at 3 days) over 15 days of storage for the physicochemical (pH; EC, electrical conductivity; TVB-N, total volatile basic nitrogen; TBARS, thiobarbituric acid reactive substances; color), microbiological (TVC, total viable count; PTC, psychrotrophic count; LAB, lactic acid bacteria; H₂S-producing bacteria), and sensory properties (color discoloration; odor; overall acceptability). The WPIf+2.5%TEO has proven enhanced quality preservation effects compared to WPIf by showing lower values for physicochemical parameters, lower microbial loads, and higher sensory scores in the fish sample. All these effects have led to an extension of the sample’s shelf-life. In conclusion, the tarragon essential oil has conferred antioxidant and antimicrobial properties to the film. Thus, the WPIf+2.5%TEO could be a promising material for the packaging of fresh brook trout during refrigerated storage.

Quality and Safety of Marinating Breast Muscles of Hens from Organic Farming after the Laying Period with Buttermilk and Whey

Simple Summary

Quality and safety are the most important features of poultry meat products for consumers. After the end of laying the meat of hens is hard, therefore methods of improving its tenderness are sought. Marinating is a frequently-used method used to improve the culinary qualities of a product. Synthetic additives for marinating meat are gaining increasingly less consumer acceptance. Acid whey and buttermilk are by-products of the dairy industry which are a source of many valuable components. The aim of this study was to evaluate marinating organic hen meat after the end of the laying period with buttermilk and whey for 24 and 48 h. In this article we have demonstrated that whey and buttermilk are suitable as natural marinades for marinating organic hen meat after laying period as they provide microbiological safety of the product and have a beneficial effect on tenderness and chewiness. In the sensory evaluation, they improve flavour and tenderness, which allows obtainment of a high-quality product.

Abstract

The material for the study was the breast muscles of hens after the laying period which were marinated with buttermilk and acid whey for 24 and 48 h. The quality parameters of non-marinated and marinated raw and roast products were evaluated in respect of physical traits (marinade absorption, pH, colour L*a*b*, shear force, TPA texture profile analysis test), microbiological parameters and sensory characteristics. The microbiological parameters were determined as the total viable counts of mesophilic aerobic bacteria of the Enterobacteriaceae family and Pseudomonas spp. Bacterial identification was performed by MALDI-TOF MS. The study showed that marinating the breast muscles of hens after the laying period with buttermilk and whey lightened the colour (p < 0.05), decreased the shear force value (p < 0.05), and reduced hardness and chewiness (p < 0.05) both after 24 and 48 h of marinating compared to the control product. The 24-h time of marinating with buttermilk and whey inhibited (p < 0.05) the growth of aerobic bacteria and Pseudomonas spp. and had a positive effect on the desirable odour, the intensity and desirability of flavour as well as the roast product tenderness. Longer marinating time reduced the product palatability and decreased its microbiological safety. The obtained results suggest that the 24-h time of marinating hen meat after the laying period with buttermilk and acid whey allows to obtainment of a high-quality product.

Microbiological Quality of Cooked Chicken: Results of Monitoring in England (2013-17)

Results from monitoring of the microbiological quality of 2,721 samples of ready-to-eat cooked chicken collected between 2013 to 2017 in England were reviewed: 70% of samples were from retail, catering or manufacture and 30% were imported and collected at English ports. Samples were tested for a range of bacterial pathogens and indicator organisms. Six samples (<1%) had unsatisfactory levels of pathogens which were potentially injurious to health. Neither Salmonella nor Campylobacter were recovered from any sample. Two samples from catering settings contained either an unsatisfactory level of Bacillus cereus (5 x 10 6 CFU/g) or an unsatisfactory level of coagulase positive staphylococci (1.6 x 10 4 CFU/g). Listeria monocytogenes was recovered from 36 samples (one at manufacture, 26 at catering and nine at retail) and in four instances, unsatisfactory levels (≥10 2 CFU/g) were detected (three samples collected at catering and one at retail). For L. monocytogenes there were no significant differences between the rates of contamination with between the samples collected from ports, manufacture, retail supermarkets and other retailers (p = 0.288). There were no differences between the rates of contamination for other potential pathogens detected between samples from different settings. The prevalence of hygiene indicators ( Escherichia coli , Enterobacteriaceae and Aerobic Colony Counts) at import was significantly lower than in samples collected from manufacturers, retail or catering (p < 0.01). Samples collected from catering gave poorer results than all other settings. Regardless of the stage in the food chain, samples from Thailand and from other non-EU countries were of significantly better microbiological quality with respect to indicator organisms than those from the UK or from other EU countries (p = <0.001).

Impact of Dietary Supplementation with Goji Berries (Lycium barbarum) on Microbiological Quality, Physico-Chemical, and Sensory Characteristics of Rabbit Meat

Forty-two New Zealand White rabbits (n = 21/group) were fed with two different diets: a commercial diet (control group) and a diet supplemented with goji berries (3% w/w). After slaughtering, the effect of dietary supplementation on microbiological, physico-chemical, and sensory characteristics of the rabbit loins, packed in an oxygen-permeable package, was evaluated at 6 h post mortem (day 0), after 4 and 10 days of refrigerated storage. No relevant results were obtained for pH and total volatile basic Nitrogen (TVBN) values but with regards to the color, some significant differences were observed between the groups. The goji berries (GBs) dietary supplementation had positive effects by reducing thiobarbituric acid reactive substances (TBARS) values in all the observations (p < 0.001). Moreover, microbiological results showed that the supplementation had a significant impact on Lactobacillus spp. (p < 0.001) prevalence, indeed the goji group had higher means on day 0 (p < 0.05) and on day 4 (p < 0.001) than the control group. Lastly, with regards to the consumer's test, the tasters assigned a higher score to GBs rabbit meatballs and the purchase interest increased when the rabbit diet was known. Overall, these results indicate that the goji berries inclusion in the rabbit diet could represent a valuable strategy to improve quality and sensory traits of meat.

Characterization and Processing of Table Olives: A Special Issue

Table olives are recognized as an essential component of the Mediterranean diet, having been explicitly included in the second level of its nutritional pyramid as an aperitif or culinary ingredient, with a recommended daily consumption of one to two portions (15–30 g). Producers demand innovative techniques improving the performance and industrial sustainability, as well as the development of new products that respond efficiently to increasingly demanding consumers. The purpose of this special issue was to publish high-quality papers with the aim to cover the state-of-the-art, recent progress and perspectives related to characterization and processing of table olives. Two reviews offer an overview about the processing and storage effects on the nutritional and sensory properties of table olives, as well as the main technologies used for olive fermentation, and the role of lactic acid bacteria and yeasts characterizing this niche during the fermentation. A total of 10 research papers cover a broad range of aspects such as characterization of their chemical composition, bioavailability, advances in the processing technology, chemical and microbiological changes, optimized use of starter cultures for the improvement of the different fermentative processes, and new strategies to reduce sodium and additives to stabilize the organoleptic properties and avoid defects.

Microbiological Quality of Ready-to-Eat Leafy Green Salads during Shelf-Life and Home-Refrigeration

The market of ready-to-eat leafy green salads is experiencing a noticeable growth in Europe. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat leafy green salads sold in widespread supermarket chains in Lazio, Italy, on the packaging date during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low-, medium-, and high-cost products. Salmonella spp. and L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the Micro Biological Survey method, in order to propose a simple, affordable and accurate alternative for testing the microbiological quality of products, especially suitable for small and medium enterprises and on-site analyses. The study revealed high, unsatisfactory, total bacterial loads in all analyzed samples on the packaging date and expiry date and a very high prevalence of Salmonella spp. (67%) regardless of the selected varieties and cost categories; L. monocytogenes was not recovered aligning with the results obtained in other studies.

Rapid Microbiological Assessment in Raw Milk: Validation of a Rapid Alternative Method for the Assessment of Microbiological Quality in Raw Milk

The consumption of dairy products and the dairy industry are one of the main global agri-food sectors for its size, economic importance, and level of technology. Microbiological quality of pasteurized milk or other milk products is dependent on microbiological quality of raw milk. A variety of microbiological count methods is available for monitoring the hygienic quality of raw milk. Among them, the pour plate method is the official essay for counting the number of colony-forming units in milk samples according to International Organization for Standardization (ISO) No. 4833-1:2013. The aim of the present study is the validation of the Micro Biological Survey (MBS) method, against the reference plate-count method, for the assessment of the microbiological quality of raw milk. This comparative study, performed in collaboration with the Istituto Zooprofilattico Sperimentale del Lazio e della Toscana M. Aleandri (IZSLT), demonstrates the accuracy of this alternative method for the determination of total viable bacterial count in cow’s raw milk. The results obtained with the MBS method highlight its potential as a valid tool for reliable microbiological analysis in dairy industries.