Long-term storage under pressure in deep sea improved the microbiological safety and physical properties of whale meat

This study aimed to clarify the effects of deep-sea pressure storage on the quality of whale meat, especially microbiological safety and physical properties, to examine the effectiveness of deep-sea storage for long-term aging of whale meat. Microbiological safety, physical properties, color and appearance, water content, water activity, and pH of whale meat were examined after storage in the deep sea at depths of 2200-6000 m (22-60 MPa) for 4 months. During storage under high pressure at a depth of >4000 m (40 MPa), the growth of aerobic bacteria was inhibited in whale meat. The toughness of whale meat stored in deep sea at a depth of >4000 m became significantly tender than that before deep-sea storage. Long-term storage of whale meat under high pressure and low-temperature conditions in the deep sea at a depth of >4000 m was clarified to improve the microbiological safety and tenderness of whale meat.

Comparison of high pressure and thermal pasteurization on the quality parameters of strawberry products: a review

Strawberry (Fragaria ananassa) is rich in bioactive compounds with high antioxidant activity. High pressure processing (HPP) is an efficient alternative to preserve these bioactive compounds in terms of microbial inactivation and shelf-life stability. This review compares the effects of pasteurization methods using high pressure or thermal pasteurization (TP) on the quality parameters of various strawberry-based products. To summarize, most of the high pressure-treated products are microbiologically stable and showed minimum degradation of thermolabile compounds than TP-treated ones. However, some studies reported that high pressure did not have an advantage over TP especially in the preservation of phenolic phytochemicals during storage. The insufficient enzyme inactivation and high residual activity of enzymes after high pressure treatment could cause anthocyanins degradation thus affecting the product quality. Overall, this review could be valuable to potential processors in evaluating the effective commercialization of high pressure-treated strawberry products.

Removal of protozoan (oo)cysts and bacteria during microalgae harvesting: Outcomes from a lab-scale experiment

The efficiency of microalgae harvesting on the removal of Giardia spp. cysts, Cryptosporidium spp. oocysts, total coliforms, Escherichia coli, Enterococcus spp. and Clostridium spp. was assessed in lab-scale experiments (Jartest and Flotatest) using effluent from a flat panel photobioreactor used for Chlorella sorokiniana cultivation. Three harvesting methods were evaluated: (1) flocculation induced by pH modulation followed by sedimentation (pH-SED), (2) flocculation induced by pH modulation followed by dissolved air flotation (pH-DAF), and (3) coagulation using an organic coagulant (Tanfloc SG) followed by dissolved air flotation (Coag-DAF). The results indicated that the three harvesting methods were efficient in removing protozoan (oo)cysts and bacteria, achieving percentages of removal higher than 97% for all the analyzed pathogens. Among the three methods, pH-SED showed the best removal performance: 99.60% (2.5 log) for Giardia spp. cysts, 100% (>6.3 log) for total coliforms, 100% (>4.6 log) for Escherichia coli, 100% (>5.8 log) for Enterococcus spp. and 99.96% (3.6 log) for Clostridium spp. Clostridium spp. seemed to be more tolerant to the harvesting methods than the other groups of bacteria analyzed in the study, and its presence was positively correlated to the presence of Giardia spp. cysts.

An assessment of the persistence of putative pathogenic bacteria in chloraminated water distribution systems

This study investigated how a chloramine loss and nitrifying conditions influenced putative pathogenic bacterial diversity in bulk water and biofilm of a laboratory- and a full-scale chloraminated water distribution systems. Fifty-four reference databases containing full-length 16S rRNA gene sequences obtained from the National Centre for Biotechnology Information database were prepared to represent fifty-four pathogenic bacterial species listed in the World Health Organisation and Australian Drinking Water Quality Guidelines. When 16S rRNA gene sequences of all samples were screened against the fifty-four reference pathogenic databases, a total of thirty-one putative pathogenic bacteria were detected in both laboratory- and full-scale systems where total chlorine residuals ranged between 0.03 - 2.2 mg/L. Pathogenic bacterial species Mycolicibacterium fortuitum and Pseudomonas aeruginosa were noted in all laboratory (i.e. in bulk water and biofilm) and in bulk water of full-scale samples and Mycolicibacterium fortuitum dominated when chloramine residuals were high. Other different pathogenic bacterial species were observed dominant with decaying chloramine residuals. This study for the first time reports the diverse abundance of putative pathogenic bacteria resilient towards chloramine and highlights that metagenomics surveillance of drinking water can serve as a rapid assessment and an early warning of outbreaks of a large number of putative pathogenic bacteria.

The prevalence of Listeria monocytogenes in meat products in China: A systematic literature review and novel meta-analysis approach

Meat products are commonly regarded as one of the main sources of human listeriosis caused by Listeria monocytogenes. The objective of this study was to estimate the prevalence of L. monocytogenes in a range of meat products from 24 different Chinese regions by using meta-analysis of literature data and a novel sensitivity analysis approach. A total of 112 publications from five databases, published between 1 January 2007 and 31 December 2017, were systematically selected for relevance and covered meat products sampled between 2000 and 2016. Estimated by the random-effects model, the pooled prevalence of L. monocytogenes was 8.5% (95% CI: 7.1%-10.3%) in raw meats and 3.2% (95% CI: 2.7%-3.9%) in ready-to-eat (RTE) meats. The prevalence differed from high to low among raw meats including prefabricated raw meats 12.6% (95% CI: 6.9%-21.7%), fresh pork 11.4% (95% CI: 8.6%-14.9%), fresh beef 9.1% (95% CI: 6.3%-13.0%), fresh poultry 7.2% (95% CI:4.9%-10.4%), frozen raw meats 7.2% (95% CI: 5.7%-9.0%), and fresh mutton 5.4% (95% CI: 2.5%-11.0%). A higher L. monocytogenes prevalence level was shown in the meat products from central and northeastern China provincial regions. The entropy-based sensitivity analysis utilized in the meta-analysis indicated that the sampling period and location were two critical factors influencing the prevalence level of L. monocytogenes in meat products. A better understanding of differences in prevalence levels per geographic region and between meat product sources may allow the competent authorities, industry, and other relevant stakeholders to tailor their interventions to control the occurrence of L. monocytogenes in meat products effectively.

Promising bacterial genera for agricultural practices: An insight on plant growth-promoting properties and microbial safety aspects

In order to address the ever-increasing problem of the world's population food needs, the optimization of farming crops yield, the combat of iron deficiency in plants (chlorosis) and the elimination/reduction of crop pathogens are of key challenges to solve. Traditional ways of solving these problems are either unpractical on a large scale (e.g. use of manure) or are not environmental friendly (e.g. application of iron-synthetic fertilizers or indiscriminate use of pesticides). Therefore, the search for greener substitutes, such as the application of siderophores of bacterial source or the use of plant-growth promoting bacteria (PGPB), is presented as a very promising alternative to enhance yield of crops and performance. However, the use of microorganisms is not a risk-free solution and the potential biohazards associated with the utilization of bacteria in agriculture should be considered. The present work gives a current overview of the main mechanisms associated with the use of bacteria in the promotion of plant growth. The potentiality of several bacterial genera (Azotobacter, Azospirillum, Bacillus, Pantoea, Pseudomonas and Rhizobium) regarding to siderophore production capacity and other plant growth-promoting properties are presented. In addition, the field performance of these bacteria genera as well as the biosafety aspects related with their use for agricultural proposes are reviewed and discussed.

Use of leftovers of monoclonal antibody products after partial extraction - A microbiological safety study

BACKGROUND/PURPOSE

In the absence of thorough microbiological, chemical and physical stability data, high amounts of pharmaceutical products, from which the seal has been broken, are to be discarded after preparation. We performed a generic microbiological validation study for several marketed monoclonal antibody products, in order to define conditions under which leftovers from partially extracted product can be used in order to minimize loss.

METHODS

From the daily practice of the Central Preparation Unit of the Netherlands Cancer Institute, used monoclonal antibody product vials were collected. To examine the integrity of the primary packaging, a VDT/S Vacuum Leak tester from Erweka was used. Vials were punctured with different types of spikes or a needle prior to experiments and examined for leakage afterward. In addition, microbiological monitoring was performed by broth simulation of the preparation method.

RESULTS

All vials (631 vials, 18 different monoclonal antibody products) showed no leakage after puncturing with a 18 G needle. However, the use of a spike system resulted in leakage in 108 of the 435 tested vials. Results from the broth simulations confirmed a higher risk of contamination after puncturing with a spike as compared to needle-punctured vials (0.5% vs. 0.05%).

CONCLUSION

When working under aseptic preparation conditions and making use of appropriate needle, the risk of contamination is acceptably low to justify storage and reuse of leftover monoclonal antibody product from a microbiological perspective. The spikes tested lead to an unacceptably high level of loss of integrity and subsequent risk of microbiological contamination if stored in a non-classified environment. We concluded that these results could be applied generically to all monoclonal antibody products with a primary packaging composed of a glass vial and rubber stopper.

Bacteriological quality and safety of ready-to-consume milk and naturally fermented milk in Borana pastoral area, southern Ethiopia

Milk and milk products play an important role in the diet of pastoralists in Ethiopia. However, only few studies have been conducted on the microbial contamination of milk and milk products in pastoral areas. Therefore, the objective of the present study was to assess the hygiene and safety of ready-to-consume milk and traditionally produced fermented milk products (yogurt) in Borana. A total of 203 raw milk and milk product samples collected from different points along the milk production and handling chains were tested for Escherichia coli, E. coli O157:H7, and Staphylococcus aureus. E. coli was detected in 51.7% of the analyzed samples with a mean count of 2.5 logCFU/ml. The study revealed that 10.8% and 2.5% of the milk and dairy product samples harbor S. aureus and E. coli O157:H7, respectively. Detection of E. coli O157:H7 in ready-to-consume milk has potential health implications for consumers in an area where raw milk consumption is common. To our knowledge, this is the first report of the isolation of E. coli O157:H7 from milk in pastoral systems in Ethiopia.

Microbiological Safety of Fresh Tilapia ( Oreochromis niloticus) from Kenyan Fresh Water Fish Value Chains

This study evaluated the microbiological safety of fresh Nile tilapia ( Oreochromis niloticus) from Kenyan fresh water fish value chains. One hundred seventy-six fish samples were analyzed. The microbial counts of hygiene indicators, total viable aerobic count (TVC), total coliforms, and fecal coliforms isolated by using culture techniques were enumerated, and microbial pathogens present in the fish samples were identified and characterized by using molecular methods. The diversity of bacterial isolates was determined by using the Shannon-Weaver diversity index. The mean of TVC in the samples was 4.44 log CFU/g. A comparison with the European Commission and International Commission on Microbiological Specifications for Foods standards showed two fish samples had counts above the 5.00 log CFU/g limit for TVC, and all the fish samples had total coliform and fecal coliform counts above 2.00 and 1.00 log CFU/g, respectively. Pathogenic strains, including Shiga toxin-producing and enteropathogenic Escherichia coli, Listeria monocytogenes, Yersinia enterocolitica, Klebsiella pneumoniae, and Salmonella enterica, were identified in the fish samples. The diversity of 1,608 bacterial isolates was higher in semiregulated chains than unregulated chains. The diversity was also high at the retail stage of the fish value chain. In conclusion, fresh Nile tilapia samples were above some of the set food safety standards and may be a source of foodborne pathogens. Further microbial risk assessment for detected pathogens is recommended to further support public health protection, taking into account growth, inactivation through cooking, processing, survival, and consumption.

Development of ginseng powder using high hydrostatic pressure treatment combined with UV-TiO2 photocatalysis

Background

Korean ginseng (Panax ginseng Meyer) powder is in rising demand because powder forms of foods are convenient to handle and are highly preservable. However, ginseng powder (GP) manufactured using the conventional process of air drying and dry milling suffers nutrient destruction and a lack of microbiological safety. The objective of this study was to prepare GP using a novel process comprised of UV-TiO₂ photocatalysis (UVTP) as a prewashing step, wet grinding, high hydrostatic pressure (HHP), and freeze-drying treatments.

Methods

The effects of UVTP and HHP treatments on the microbial population, ginsenoside concentration, and physiological characteristics of GP were evaluated.

Results

When UVTP for 10 min and HHP at 600 MPa for 5 min were combined, initial 4.95 log CFU/g-fw counts of total aerobes in fresh ginseng were reduced to lower than the detection limit. The levels of 7 major ginsenosides in UVTP-HHP–treated GP were significantly higher than in untreated control samples. Stronger inhibitory effects against inflammatory mediator production and antioxidant activity were observed in UVTP-HHP–treated GP than in untreated samples. There were also no significant differences in CIELAB color values of UVTP-HHP–treated GP compared with untreated control samples.

Conclusion

Combined processing of UVTP and HHP increased ginsenoside levels and enhanced the microbiological safety and physiological activity of GP.

Effects of sous-vide method at different temperatures, times and vacuum degrees on the quality, structural, and microbiological properties of pork ham

This study evaluated the influence of different factors on pork hams cooked by sous-vide method. The quality and structural and microbiological properties of the treated samples were compared with those of controls. Samples were subjected to treatment at different combinations of temperature (61 °C or 71 °C), time (45 or 90 min), and vacuum degree (98.81% or 96.58%). The control sample was air packaged and boiled for 45 min in boiling water. Temperature and vacuum degree affected quality properties, while the effect of time was limited. Samples cooked at 61 °C showed higher moisture content, redness, and pink color of the meat juice, whereas samples cooked at 71 °C showed higher cooking loss rate, lightness, and volatile basic nitrogen values. Texture analysis indicated tenderer meat for the treatment group than the control. No microbial growth was detected in any treatment groups. Meat cooked at 61 °C and 98.81% vacuum showed more spacious arrangement of meat fiber.

Detection of the relatively slow-growing Propionibacterium acnes in seven matrices of blood components and advanced therapeutical medicinal products

BACKGROUND

Relatively slow-growing bacteria like Propionibacterium acnes represent a challenge for quality control investigations in sterility release testing of blood components and advanced therapeutic medicinal products (ATMPs).

METHODS

A convenient validation with 7 matrices was performed using buffy coat, stem cells, islet cells, natural killer cells, red blood cells, platelets and plasma in the microbial detection system Bact/Alert^®3D incubator. All matrix samples were spiked twofold with Propionibacterium acnes with approximately 50 colony forming units (CFUs) per bottle in iAST and iNST culture bottles for 14days using a multishot bioball. Additionally, the stem cell preparations were also incubated in iFAplus and iFNplus culture bottles, which include neutralizing polymers.

RESULTS

The Bact/Alert^®3D-System detected Propionibacterium acnes in anaerobic culture bottles in buffy coat [3.3 d (=positive signal day to detection as mean value)], red blood cells [3.2 d], platelets [3.3], plasma [3.7 d], natural killer cells [3.3 d] and islet cells [4.9 d], resp. No growth of Propionibacterium was found in autologous stem cells using iAST and iNST culture bottles. However, Propionibacterium was safely detected in the iFNplus culture bottle with polymers in the stem cell matrix. A successful validation of media was performed.

CONCLUSIONS

Our study shows that Bact/Alert^®3D-System safely detects the relatively slow-growing bacterium Propionibacterium acnes in different matrices in a practical way except stem cells. Using the iFNplus culture bottle for stem cell products positive signals were observed.

Microbiological Safety of Street Vended Foods in Jigjiga City, Eastern Ethiopia

Background

Food safety problems are particularly becoming an increasingly serious threat to public health in developing countries. This study was conducted to assess microbiological safety of street vended foods from May to November, 2014 in Jigjiga City.

Methods

A cross-sectional design was used to answer questions concerning the current status of food hygiene and sanitation practire of street food vending sites. Interview and observational assessments were used to collect socio-demographic data about street food venders. One hundred thirty-two samples of street foods were aseptically collected from four ‘kebeles’ of Jigjiga City. Both descriptive and analytical statistical methods were applied.

Results

The majority of the street food vendors were women, 120(90.9%), with the average age group of 23–49 years, (42.85%), and 99(66.7%) them were illiterate. The study revealed that 95(72%) of the food samples had pathogenic bacterial contaminations. Three different bacterial species were isolated: E. coli 68(51.5%), S. aureus 85(64.4%) and 26(19.7%) Salmonella species. The highest incidence of S. aureus 23/33(69%) was seen in ‘Sambusa’; the highest incidence of E. coli 24/33(73.5%) was observed in ‘Pasta’, while the highest Salmonella incidence was observed in ‘Ades’

Conclusion

This study revealed that there is a reasonable gap on food safety knowledge among street food venders. The microbial profile was also higher compared to standards set by the World Health Organization. Due attention should be given by the government to improve knowledge about food safety and the quality standard of street foods sold in the City.

Safety aspects of the production of foods and food ingredients from insects

At present, insects are rarely used by the European food industry, but they are a subject of growing interest as an alternative source of raw materials. The risks associated with the use of insects in the production of foods and food ingredients have not been sufficiently investigated. There is a lack of scientifically based knowledge of insect processing to ensure food safety, especially when these processes are carried out on an industrial scale. This review focuses on the safety aspects that need to be considered regarding the fractionation of insects for the production of foods and food ingredients.

Shelf-life and microbiological safety studies of refrigerated petha sweet

This study was conducted at Indian Institute of Vegetable Research, Varanasi (I.I.V.R.), Uttar Pradesh from 2006 to 2009 for evaluating comparative physico-chemical, microbiological and sensory attributes of crystallized and Kashi petha at refrigerated storage (4 ± 1 °C) condition up to 90 days. The petha were manufactured using 2 varieties of ash gourd developed at I.I.V.R. i.e.; Kashi Dhawal and Kashi Ujwal, selected based on different parameters suitable for petha sweet preparation. The used packaging materials for storage studies were laminated pouch, low density polyethylene, high density polyethylene. The physiochemical analysis and sensory evaluation were performed at 15 days interval upto 90 days for storage study in both Kashi Petha and crystallized petha, while microbial observation was recorded up to 90 days in crystallized petha and up to 50 days Kashi Petha. Physico-chemical analysis exhibited the continuous increase in moisture (25.79-26.80 % and 31.68-32.63 %) and titratable acidity (0.022-0.029 %) and (0.022-0.030 %) and reduction in ascorbic acid content (5.50-5.00 mg/100 g and 5.12-4.84 mg/100 g), respectively in crystallized and Kashi petha. The increasing trend in microbial population was more pronounced in Kashi petha in comparison to crystallized petha. The spoilage bacteria included Bacillus spp., Staphylococcus spp. and lactic acid bacteria while Aspergillus, Penicillium and Saccharomyces were observed among fungal contaminants. The bacteria, yeast and mold were identified on the basis of cultural, morphological and biochemical characterization with respect to storage period. On the basis of the overall findings of comparative physico-chemical, microbiological and sensory evaluation, 30 and 50 days of storage was considered as safe for the consumption of Kashi and crystallized petha, respectively under refrigerated environment (4 ± 1 °C).

[Current concept for the microbiological safety of cell-based medicinal products]

Ensuring microbiological safety in advanced-therapy medicinal products is still a big challenge for manufacturers. There are fundamental problems, especially in cell-based medicinal products, regarding sterility of source materials, short shelf-life of final products, and the selection of suitable microbiological methods. Different from classical medicinal products, there is the need to evaluate a large number of possible risks and to calculate the risk-benefit balance. Depending on the source material, the presence of micro-organisms with specific growth requirements has to be considered. They cannot be detected by conventional testing methods, but may replicate after the application of the preparation in the recipient. Mycoplasmas are the primary representatives of these contaminants and specific testing procedures are required. Additionally, depending on the source and processing of the biological material, specific testing methods for mycobacteria and other contaminants should be included. Alternative microbiological methods (e.g. NAT, flow cytometry) should be applied in order to reduce the time to detection and to provide reliable results before application of a preparation, but should be also assessed for their possible use for the detection of conventionally undetectable micro-organisms.

Microbial evaluation of sandboxes located in urban area

This paper presents the results of a study on the degree of bacteriological pollution of sandboxes situated in fenced and unfenced housing estates located in an urban area in Olsztyn, Poland. Heterotrophic plate counts (HPC22, HPC37), Enterobacteriaceae, Escherichia coli, Enterococcus spp., Staphylococcus spp. and Clostridium perfringens determined by cultivation and fluorescence in situ hybridization (FISH) methods were used as indicators of the sanitary state. Their maximum number in the sand samples reached values of up to 5.4×10(7), 2.6×10(6), 3.3×10(4), 2.1×10(3), 1.8×10(4), 1.9×10(1) and 1.2×10(4)CFU/g, respectively. It was found that values of culture-independent method were two-four orders greater than those obtained by the cultivation method. Among identified Enterobacteriaceae, Pantoea spp. and Enterobacter cloacae were the most numerous, whereas Escherichia cells were detected only occasionally. Pathogenic bacteria of the genus Salmonella sp. were isolated from sandboxes also when E. coli were absent. Bacteria from Staphylococcus genus were isolated irrespective of the site and time of sampling. Additionally, the presence of molds and yeasts was studied. Maximum counts of these microorganisms amounted to 1.0×10(5) and to 3.5×10(4)CFU/g. Aspergillus, Penicillium, Alternaria and Trichoderma genera were most numerous among molds, whereas Trichosporon was detected most frequently among yeasts. Sandboxes in the fenced housing estate and those located in the area which is not close to trees were less polluted than the sand collected from sandboxes in the unfenced housing estate. Potentially pathogenic bacteria of the genus Salmonella spp. were identified in analyzed sandboxes, also when Toxocara and E. coli were absent. It seems that assessing the contamination of children's play areas basing only on fecal bacteria counts and by monitoring number of parasites' eggs may be insufficient to evaluate microbial pollution of sandboxes and may not fully reflect their safety for children.

Impact of cyadox on human colonic microflora in chemostat models

The aim of this study was to evaluate the microbiological safety of cyadox, a new member of quinoxaline-1,4-dioxides (QdNOs), on human intestinal flora. Four chemostats containing human fecal flora were exposed to 0, 16, 32, and 128 μg/mL of cyadox, respectively. Bacterial populations, resistance rates of two predominant bacteria and short-chain fatty acids (SCFA) were monitored daily prior to and during drug MOA Laboratory of Risk Assessment for Quality and Safety of Livestock and Poultry Products exposure. Colonization resistance (CR) of each community was determined by three successive daily challenges of Salmonella typhimurium. Efflux pump gene (oqxAB) in the Escherichia coli and Enterococcus strains were analyzed by PCR amplification and DNA sequencing. No change in SCFA was observed after exposure to different concentrations of cyadox. Lower concentration of cyadox (16 μg/mL) had no adverse effect on human microflora. However, higher concentrations of cyadox (32 and 128 μg/mL) could change bacterial population and increase the proportion of resistant E. coli and Enterococcus. More than 26% (12/46) of cyadox resistant E. coli strains contained oqxAB gene, while all the resistant Enterococcus were negative to oqxAB gene. Relationship between the occurrence of oqxAB gene and cyadox exposure is inconclusive. Our data indicated that 16 μg/mL might be the no observed effect concentration (NOEC) of cyadox. Derived microbiological acceptable daily intake (mADI) would be 1552.03 μg/kg d. The data obtained in present study indicated that cyadox was a safe member of QdNOs family of antimicrobial agents.