Non-thermal technologies and its current and future application in the food industry: a review

Extraction of polyphenols and essential oils from herbs with green extraction methods - An insightful review

The demand for polyphenols and essential oils (EOs) on the food market is high and grows every year. Its partially the result of the fact that these compounds can be used in formulation of clean label foods, a fast growing food sector. A significant share of polyphenols and EOs are extracted from herbs. The quality of the extracts is determined mainly by the extraction method. Conventional extraction techniques of phytochemicals are time-consuming, operate at high temperatures, and require usage of organic solvents and energy in large quantities. According to the United Nations Sustainability Development Plan, chemical processes should be replaced by green alternatives that would reduce the use of solvents and energy. Ultrasound-Assisted Extraction (UAE), Microwave-Assisted Extraction (MAE) and Cold Plasma-Assisted Extraction (CPAE) meets these criteria. The review shows that each of these techniques seems to be a great alternative for conventional extraction methods ensuring higher yields of bioactive compounds.

Natural pigments in the food industry: Enhancing stability, nutritional benefits, and gut microbiome health

Natural pigments are increasingly favored in the food industry for their vibrant colors, fewer side effects and potential health benefits compared to synthetic pigments. However, their application in food industry is hindered by their instability under harsh environmental conditions. This review evaluates current strategies aimed at enhancing the stability and bioactivity of natural pigments. Advanced physicochemical methods have shown promise in enhancing the stability of natural pigments, enabling their incorporation into food products to enhance sensory attributes, texture, and bioactive properties. Moreover, recent studies demonstrated that most natural pigments offer health benefits. Importantly, they have been found to positively influence gut microbiota, in particular their regulation of the beneficial and harmful flora of the gut microbiome, the reduction of ecological dysbiosis through changes in the composition of the gut microbiome, and the alleviation of systemic inflammation caused by a high-fat diet in mice, suggesting a beneficial role in dietary interventions.

Betalains from vegetable peels: Extraction methods, stability, and applications as natural food colorants

Betalains are hydrophilic pigments naturally present in a limited number of plants and fungi. In addition to providing pigmentation, ranging from yellow to red, they show potential for replacing artificial food colorings. Betalains can be obtained from agri-food waste like vegetable peels through conventional and emerging extraction methods; however, they are susceptible to chemical changes due to various degradation factors, such as the presence of oxygen, light, and increased temperature. In this context, encapsulation can be used as a strategy to stabilize and reduce the pigment degradation rate for later industrial application in processed foods. This study reviews data from the last five years on the production and relevance of valuing agri-food waste, in addition to research carried out on betalains obtained from vegetable peels, such as extraction methods, encapsulation as a method of controlling stability and applications as colorant in food matrices, highlighting news insights for the field of pigments from plant sources. This review shows that encapsulation techniques using mixtures of wall materials offer superior protection than isolated materials. Despite advances in applicability, gaps still persist regarding stability in food matrices, especially on an industrial scale. However, future investigations should focus on filling the gaps regarding the maintenance of the properties of betalains for application in food industries as natural food coloring based on the precepts of circular economy and sustainable technology.

Electromagnetic wave-based technology for ready-to-eat foods preservation: a review of applications, challenges and prospects

In recent years, the ready-to-eat foods market has grown significantly due to its high nutritional value and convenience. However, these foods are also at risk of microbial contamination, which poses food safety hazards. Additionally, traditional high-temperature sterilization methods can cause food safety and nutritional health problems such as protein denaturation and lipid oxidation. Therefore, exploring and developing effective sterilization technologies is imperative to ensure food safety and nutritional properties, and protect consumers from potential foodborne diseases. This paper focuses on electromagnetic wave-based pasteurization technologies, including thermal processing technologies such as microwave, radio frequency, and infrared, as well as non-thermal processing technologies like ultraviolet, irradiation, pulsed light, and photodynamic inactivation. Furthermore, it also reviews the antibacterial mechanisms, advantages, disadvantages, and recent applications of these technologies in ready-to-eat foods, and summarizes their limitations and prospects. By comparing the limitations of traditional high-temperature sterilization methods, this paper highlights the significant advantages of these pasteurization techniques in effectively inhibiting microbial growth, slowing lipid oxidation, and preserving food nutrition and flavor. This review may contribute to the industrial application and process optimization of these pasteurization technologies, providing an optimal choice for preserving various types of ready-to-eat foods.

Post-harvest bacterial contamination of fish, their assessment and control strategies

Healthy fish populations lead to healthy aquatic ecosystems and it is our responsibility to be a part of the solution. Fish is one of the most favored foods and is suitable for people of all ages. Fish is an essential source of protein, vitamins, and minerals and a source of income for millions of people. Human population growth and climate change are putting a strain on our food system, demanding the development of sustainable services to enhance global food production and its security. Food safety is an intricate problem in both developed and developing countries. Fresh fish is a highly perishable food with a limited life span; as a result, it must be delivered and kept carefully to minimize deterioration and assure safety. Fish spoilage is linked to biochemical changes that occur post-harvest, such as storage and transportation. These modifications can account for fish spoilage by altering the taste, texture, and appearance. Fish harvesting, distribution, and post-harvest handling are all unhygienic, resulting in poor and unpredictable fish quality in the market. Many innovative and effective control measurements of various bacteria in fish have been proposed and evaluated. This review is a systematic approach to investigating post-harvest fish spoilage, its assessment, and control strategies.

Impact of Ultrasound Pre-Treatment on the Drying Kinetics and Quality of Chicken Breast-A Comparative Study of Convective and Freeze-Drying Methods

Fresh meat has a limited shelf life and is prone to spoilage. Drying serves as a common method for food preservation. Non-thermal techniques such as ultrasound treatment (US) can positively affect the drying processes and alter the final product. The study aimed to evaluate the impact of US pre-treatment on the hot air (HA) and freeze-drying (FD) of chicken breast meat and the quality of the dried products. US pre-treatment had a varied impact depending on the drying method used. The contact US method extended the HA drying time (about 50%) but improved water removal during FD (about 30%) compared to the untreated samples. Both methods resulted in low water content (<8.3%) and low water activity (<0.44). While rehydration properties (RR) and hygroscopicity (H) were not significantly affected by US pre-treatment in HA drying (about 1.35% and about 1.1, respectively), FD noticed differences due to shrinkage and porosity variations (RR: 2.4-3.2%, H: 1.19-1.25). The HA-dried samples exhibited notably greater tissue shrinkage and a darker surface color than the FD meat. Ultrasonic processing holds substantial potential in creating dried meat products with tailored characteristics. Hence, meticulous consideration of processing methods and parameters is of utmost importance.

Algae-Boosted Chickpea Hummus: Improving Nutrition and Texture with Seaweeds and Microalgae

The global food industry faces a critical challenge in ensuring sustainable practices to meet the demands of a growing population while minimizing environmental impact. At the same time, consumer awareness and the demand for quality products drive innovation and inspire positive changes in the food supply chain. Aiming to create a more sustainable and nutrient-rich alternative, this study is summarized by characterizing the physical and chemical characteristics of algae-enriched chickpea hummus: an innovative approach to popular food products. The algae-enriched hummuses were developed with an incorporation (6% w/w) of Gelidium corneum and Fucus vesiculosus seaweeds and Chlorella vulgaris (hetero and autotrophic) microalgae to reveal their technological potential and evaluate the nutritional and rheological characteristics relative to a control hummus (without algae). From a nutritional perspective, the main results indicated that hummus enriched with microalgae showed an increase in protein content and an improved mineral profile. This was particularly notable for the seaweed F. vesiculosus and the autotrophic microalga C. vulgaris, leading to claims of being a "source of" and "rich in" various minerals. Additionally, the antioxidant activity of hummus containing F. vesiculosus and C. vulgaris increased significantly compared to the control. From a rheological perspective, incorporating algae into the humus strengthened its structure. The microalgae further enhanced the dish's elasticity and firmness, thus improving this chickpea-based dish´s overall texture and quality.

Green Methods to Recover Bioactive Compounds from Food Industry Waste: A Sustainable Practice from the Perspective of the Circular Economy

The worrying and constant increase in the quantities of food and beverage industry by-products and wastes is one of the main factors contributing to global environmental pollution. Since this is a direct consequence of continuous population growth, it is imperative to reduce waste production and keep it under control. Re-purposing agro-industrial wastes, giving them new life and new directions of use, is a good first step in this direction, and, in global food production, vegetables and fruits account for a significant percentage. In this paper, brewery waste, cocoa bean shells, banana and citrus peels and pineapple wastes are examined. These are sources of bioactive molecules such as polyphenols, whose regular intake in the human diet is related to the prevention of various diseases linked to oxidative stress. In order to recover such bioactive compounds using more sustainable methods than conventional extraction, innovative solutions have been evaluated in the past decades. Of particular interest is the use of deep eutectic solvents (DESs) and compressed solvents, associated with green techniques such as microwave-assisted extraction (MAE), ultrasonic-assisted extraction (UAE), pressurized liquid extraction (PLE) and pulsed-electric-field-assisted extraction (PEF). These novel techniques are gaining importance because, in most cases, they allow for optimizing the extraction yield, quality, costs and time.

Acid-Heat-Induced Fabrication of Nisin-Loaded Egg White Protein Nanoparticles: Enhanced Structural and Antibacterial Stability

As a natural cationic peptide, Nisin is capable of widely inhibiting the growth of Gram-positive bacteria. However, it also has drawbacks such as its antimicrobial activity being susceptible to environmental factors. Nano-encapsulation can improve the defects of nisin in food applications. In this study, nisin-loaded egg white protein nanoparticles (AH-NEn) were prepared in fixed ultrasound-mediated under pH 3.0 and 90 °C. Compared with the controls, AH-NEn exhibited smaller particle size (112.5 ± 2.85 nm), smaller PDI (0.25 ± 0.01), larger Zeta potential (24 ± 1.18 mV), and higher encapsulation efficiency (91.82%) and loading capacity (45.91%). The turbidity and Fourier transform infrared spectroscopy (FTIR) results indicated that there are other non-covalent bonding interactions between the molecules of AH-NEn besides the electrostatic forces, which accounts for the fact that it is structurally more stable than the controls. In addition, by the results of fluorescence intensity, differential scanning calorimetry (DSC), and X-ray diffraction (XRD), it was shown that thermal induction could improve the solubility, heat resistance, and encapsulation of nisin in the samples. In terms of antimicrobial function, acid-heat induction did not recede the antimicrobial activity of nisin encapsulated in egg white protein (EWP). Compared with free nisin, the loss rate of bactericidal activity of AH-NEn was reduced by 75.0% and 14.0% following treatment with trypsin or a thermal treatment at 90 °C for 30 min, respectively.

High pressure processing plus technologies: Enhancing the inactivation of vegetative microorganisms

High pressure processing (HPP) is a non-thermal technology that can ensure microbial safety without compromising food quality. However, the presence of pressure-resistant sub-populations, the revival of sub-lethally injured (SLI) cells, and the resuscitation of viable but non-culturable (VBNC) cells pose challenges for its further development. The combination of HPP with other methods such as moderate temperatures, low pH, and natural antimicrobials (e.g., bacteriocins, lactate, reuterin, endolysin, lactoferrin, lactoperoxidase system, chitosan, essential oils) or other non-thermal processes (e.g., CO2, UV-TiO2 photocatalysis, ultrasound, pulsed electric fields, ultrafiltration) offers feasible alternatives to enhance microbial inactivation, termed as "HPP plus" technologies. These combinations can effectively eliminate pressure-resistant sub-populations, reduce SLI or VBNC cell populations, and inhibit their revival or resuscitation. This review provides an updated overview of microbial inactivation by "HPP plus" technologies and elucidates possible inactivation mechanisms.

A comprehensive review of mycotoxins: Toxicology, detection, and effective mitigation approaches

Mycotoxins, harmful compounds produced by fungal pathogens, pose a severe threat to food safety and consumer health. Some commonly produced mycotoxins such as aflatoxins, ochratoxin A, fumonisins, trichothecenes, zearalenone, and patulin have serious health implications in humans and animals. Mycotoxin contamination is particularly concerning in regions heavily reliant on staple foods like grains, cereals, and nuts. Preventing mycotoxin contamination is crucial for a sustainable food supply. Chromatographic methods like thin layer chromatography (TLC), gas chromatography (GC), high-performance liquid chromatography (HPLC), and liquid chromatography coupled with a mass spectrometer (LC/MS), are commonly used to detect mycotoxins; however, there is a need for on-site, rapid, and cost-effective detection methods. Currently, enzyme-linked immunosorbent assays (ELISA), lateral flow assays (LFAs), and biosensors are becoming popular analytical tools for rapid detection. Meanwhile, preventing mycotoxin contamination is crucial for food safety and a sustainable food supply. Physical, chemical, and biological approaches have been used to inhibit fungal growth and mycotoxin production. However, new strains resistant to conventional methods have led to the exploration of novel strategies like cold atmospheric plasma (CAP) technology, polyphenols and flavonoids, magnetic materials and nanoparticles, and natural essential oils (NEOs). This paper reviews recent scientific research on mycotoxin toxicity, explores advancements in detecting mycotoxins in various foods, and evaluates the effectiveness of innovative mitigation strategies for controlling and detoxifying mycotoxins.

A multidimensional evaluation of the effects of sweetener selection and UV-C treatment on orange juice and pectin-based confectionery gels

BACKGROUND

Consumers are seeking healthier alternatives to traditional confectioneries. They value the use of sugar replacers, more natural ingredients and/or environmentally friendly preservation technologies. UV-C light is considered an emerging alternative to thermal pasteurization that leaves no residue and requires minimal energy. The present study aimed to investigate the effect of novel sweetener combinations and juice UV-C assisted by mild heat treatment (UV-C/H) on the physicochemical, microbiological, morphological, rheological and sensory properties of orange juice pectin-based confectioneries stored at 5 ± 1 °C for 35 days.

RESULTS

For orange juice processing, UV-C/H (pilot-scale Dean-flow reactor; 892 mJ cm-2 ; 50 ± 1 °C) and thermal (T-coil, 80 °C; 6 min) treatments were used. Low-calorie confectionery gels were elaborated using the treated juices, low-methoxyl pectin and various sweetener combinations. UV-C/H and T-coil effectively inactivated juice native microbiota. The proposed formulations, derived from a previous Box-Behnken optimization study, included partial (F1: 3%-sucrose-S + 0.019%-rebaudioside-A-RA) or complete sucrose replacement (F2: 5.5%-erythritol-E + 0.019%-RA), and one control (C:10%-S). In general, the microbiota of the gels prepared with the UV-C/H or T-coil treated juices did not recover during storage. The physicochemical and mechanical parameters of the formulations were significantly influenced by the choice of sweetener and the duration of storage. The gel surface got smoother and had fewer holes when the sucrose level dropped, according to a scanning electron microscopy study. The UV-C/H-treated samples did not differ in acceptability, whereas the measured sensory attributes approached ideal levels. F1 and F2 showed distinctive temporal-dominance-of-sensations profiles, mainly dominated by sweetness and orange taste, respectively. However, consumers perceived sourness and astringency in C during consumption.

CONCLUSION

The present study provides significant evidence in support of the development of confectionery gels F1 and F2 made from fruit juice treated by UV-C light assisted by mild heat and combinations of sucrose-alternative sweeteners. In terms of the properties investigated, these confectionery gels were comparable to, or even outperformed the full-sucrose option. © 2023 Society of Chemical Industry.

Effect of Optimized UV-LED Technology on Modeling, Inactivation Kinetics and Microbiological Safety in Tomato Juice

This research analyzed, optimized and modeled the inactivation kinetics of pathogenic bacteria (PB1: Escherichia coli O157:H7 and PB2: Listeria monocytogenes) and determined the microbiological safety of tomato juice processed by UV-LED irradiation and heat treatment. UV-LED processing conditions were optimized using response surface methodology (RSM) and were 90% power intensity, 21 min and 273-275 nm (251 mJ/cm2) with R2 > 0.96. Using the optimal conditions, levels of PB1 and PB2 resulted a log reduction of 2.89 and 2.74 CFU/mL, respectively. The Weibull model was efficient for estimating the log inactivation of PB1 and PB2 (CFU/mL). The kinetic parameter δ showed that 465.2 mJ/cm2 is needed to achieve a 90% log (CFU/mL) reduction in PB1 and 511.3 mJ/cm2 for PB2. With respect to the scale parameter p > 1, there is a descending concave curve. UV-LED-treated tomato juice had an 11.4% lower Listeria monocytogenes count than heat-treated juice on day 28 (4.0 ± 0.82 °C). Therefore, UV-LED technology could be used to inactivate Escherichia coli O157:H7 and Listeria monocytogenes, preserving tomato juice for microbiological safety, but studies are required to further improve the inactivation of these pathogens and analyze other fruit and vegetable juices.

Pulsed electric field technology as a promising pre-treatment for enhancing orange agro-industrial waste biorefinery

In the processing of orange juice, 50-70% of the fresh fruit weight is converted into organic waste. Orange processing waste (OPW) primarily consists of peels, seeds, and pulp. Improper disposal of this residue can lead to greenhouse gas emissions, environmental pollution, and the wastage of natural resources. To address this ecological issues, recent research has focused on developing innovative process designs to maximize the valorization of OPW through biorefinery strategies. However, the current challenge in implementing these methods for industrial waste management is their significant energy consumption. In response to these challenges, recent studies have explored the potential of employing pulsed electric field (PEF) technology as a pre-treatment to improve energy efficiency in biorefinery processes. This non-thermal and emerging technology can enhance the mass transfer of intracellular components via electroporation of cell walls, thereby resulting in shorter processing times, lower energy inputs, greater retention of thermosensitive components, and higher extraction yields. In this regard, this review offers a comprehensive discussion on the innovative biorefinery strategies to the valorization of OPW, with a specific focus on recent studies assessing the technical feasibility of methodologies for the extraction of phytochemical compounds, dehydration processes, and bioconversion methods. Recent studies that discussed the potential of PEF technology to reduce energy demand by increasing the mass transfer of biological tissues were emphasized.

Integrated ESI-MS/MS and APCI-MS/MS based metabolomics reveal the effects of canning and storage on peach fruits

The characterization of peach metabolites and carotenoids during canning and storage remains unclear. The present study identified 658 metabolites and 40 carotenoids in peach fruits throughout the canning and storage using ESI-MS/MS and APCI-MS/MS based metabolome approach. A total of 282 differentially accumulated metabolites were found, mainly including 78 phenolic acids, 74 lipids, 61 flavonoids. Five esterified carotenoids (rubixanthin palmitate, β-cryptoxanthin oleate, β-cryptoxanthin laurate, β-cryptoxanthin palmitate, and β-cryptoxanthin myristate) were the main peach carotenoids, with a proportion of approximately 90%, while free carotenoids accounted for 4.22-5.95% during the entire processing period. Moreover, the total carotenoid loss rates for canning and storage were 56.67% and 46.55%, respectively. Compared to the loss of free carotenoids, esterified carotenoids were more stable during storage, while canning led to a greater loss of esterified carotenoids. The results provided new insights into the maintenance of health-related phytochemicals from canning processes.

The Application of High-Hydrostatic-Pressure Processing to Improve the Quality of Baked Products: A Review

The current trend in the food industry is towards "clean label" products with high sensory and nutritional quality. However, the inclusion of nutrient-rich ingredients in recipes often leads to sensory deficiencies in baked goods. To meet these requirements, physically modified flours are receiving more and more attention from bakery product developers. There are various findings in the literature on high hydrostatic pressure (HHP) technology, which can be used to modify various matrices so that they can be used as ingredients in the baking industry. HHP treatments can change the functionality of starches and proteins due to cold gelatinization and protein unfolding. As a result, the resulting ingredients are more suitable for nutrient-rich bakery formulations. This review describes the information available in the literature on HHP treatment conditions for ingredients used in the production of bakery products and analyses the changes in the techno-functional properties of these matrices, in particular their ability to act as structuring agents. The impact of HHP-treated ingredients on the quality of dough and bakery products and the effects on some nutritional properties of the treated matrices have been also analysed. The findings presented in this paper could be of particular interest to the bakery industry as they could be very useful in promoting the industrial application of HHP technology.

Analyzing the pressure resistant, sublethal injury and resuscitable viable but non-culturable state population of Escherichia coli, Staphylococcus aureus, Bacillus amyloliquefaciens and Lactiplantibacillus plantarum under high pressure processing

This study aimed to analyze and reduce the pressure resistance (PR), sublethal injury (SLI), and viable but non-culturable (VBNC) populations during HPP. Escherichia coli, Staphylococcus aureus, Bacillus amyloliquefaciens and Lactiplantibacillus plantarum were selected for evaluation of PR, SLI and VBNC cell counts and proportions during HPP. The results revealed that the bactericidal efficiency against these strains gradually improved as the processing pressure increased. However, viable bacteria could still be detected, suggesting that there may involve the presence of resistant population that difficult to be killed or revived from SLI. Further detecting the quantity and proportion of PR, SLI and VBNC bacteria found that these state of cells were present during whole HPP treatment. Additionally, the more resistant a bacterial species was to high pressure, the fewer SLI and more resuscitable VBNC (RVBNC) populations it generated, and vice versa. Therefore, correlation analysis was also employed to make the relationship between log reduction, SLI and RVBNC population ratios clearer. The results demonstrated that the log reduction was highly positive correlation with SLI population ratios, and negative correlation with RVBNC population within our detected species at 500 MPa. Furthermore, CO2 and Nisin were employed to combined with HPP to reduce these survivors. Comparing with 233, 218, 241 and 259 MPa for HPP treatment, it took 37, 89, 135 and 229 MPa for HPP + CO2, and 189, 161, 199 and 292 MPa for HPP + Nisin to the first decimal reduction for E. coli, S.aureus, B. amyloliquefaciens and L. plantarum, respectively. The results indicated that HPP combined with CO2 or Nisin could significantly reduce the quantity of PR, SLI, and RVBNC cells during HPP, and provide better bactericidal effects. In conclusion, we quantified the presence of PR, SLI, and VBNC bacteria after high pressure treatment and investigate the effectiveness of HPP combined with CO2 or Nisin to enhance the inactivation of bacteria and reduce the occurrence of PR, SLI, and RVBNC bacteria.

Implications of Pulsed Electric Field Pre-Treatment on Goat Milk Pasteurization

Goat milk is an interesting product from a nutritional and health standpoint, although its physico-chemical composition presents some technological challenges, mainly for being less stable than cow's milk at high temperatures. As pasteurization and ultra-high temperature processing are universally employed to ensure milk quality and safety, non-thermal methods, such as pulsed electric fields (PEFs), reduce the microbial load and eliminate pathogens, representing an interesting alternative for processing this product. This study demonstrates how the combined use of a PEF with short thermal processing and moderate temperature can be effective and energy-efficient in goat milk processing. A combination of thermal treatment at 63 °C after a low-intensity PEF (50 µs pulses, 3 Hz, and 10 kV·cm-1) caused the same reduction effect on the population of Listeria monocytogenes (goat's raw milk artificially spiked), as compared to a thermal treatment at 72 °C without a PEF. However, z values are significantly higher when PEF is used as a pre-treatment, suggesting that it may induce heat resistance in the survival population of L. monocytogenes. The sensitivity of L. monocytogenes to high temperatures is less pronounced in goat's milk than cow's milk, with a more pronounced impact of a PEF on lethality when combined with lower temperatures in goat's milk. The effect of a PEF on Escherichia coli viability was even more pronounced. It was also observed that thermal treatment energy needs with a PEF as a pre-treatment can be reduced by at least 50% of the total energy requirements.

Recent Advances in Acoustic Technology in Food Processing

The development of food industry technologies and increasing the sustainability and effectiveness of processing comprise some of the relevant objectives of EU policy. Furthermore, advances in the development of innovative non-thermal technologies can meet consumers' demand for high-quality, safe, nutritious, and minimally processed foods. Acoustic technology is characterized as environmentally friendly and is considered an alternative method due to its sustainability and economic efficiency. This technology provides advantages such as the intensification of processes, increasing the efficiency of processes and eliminating inefficient ones, improving product quality, maintaining the product's texture, organoleptic properties, and nutritional value, and ensuring the microbiological safety of the product. This review summarizes some important applications of acoustic technology in food processing, from monitoring the safety of raw materials and products, intensifying bioprocesses, increasing the effectiveness of the extraction of valuable food components, modifying food polymers' texture and technological properties, to developing biodegradable biopolymer-based composites and materials for food packaging, along with the advantages and challenges of this technology.

Bacteria intrinsic to Medicago sativa (alfalfa) reduce Salmonella enterica growth in planta

AIMS

The purpose of this study was to determine whether plant-associated bacteria (PAB) can reduce Salmonella enterica colonization and infection of alfalfa sprouts to reduce the risk of foodborne illness.

METHODS

We isolated PAB from alfalfa seeds and sprouts. Monoclonal isolates of the bacteria were obtained and tested for their ability to inhibit Salmonella Typhimurium growth in alfalfa sprouts over 6 days. Genome sequencing and annotation were used to construct draft genomes of the bacteria isolated in this study using Illumina sequencing platform.

RESULTS

We observed that a cocktail of five PAB could reduce Salmonella growth in alfalfa sprouts from ∼108 to ∼105 CFU g-1, demonstrating a protective role. Genome sequencing revealed that these bacteria were members of the Pseudomonas, Pantoea, and Priestia genus, and did not possess genes that were pathogenic to plants or animals.

CONCLUSIONS

This work demonstrates that PAB can be utilized to reduce pathogen levels in fresh produce, which may be synergistic with other technologies to improve the safety of sprouts and other fresh produce.

The effects of ultrasound on probiotic functionality: an updated review

The effects of ultrasound (US) on probiotics, as health-promoting microbes, have attracted the attention of researchers in fermentation and healthy food production. This paper aims to review recent advances in the application of the US for enhancing probiotic cells' activity, elaborate on the mechanisms involved, explain how probiotic-related industries can benefit from this emerging food processing technology, and discuss the perspective of this innovative approach. Data showed that US could enhance fermentation, which is increasingly used to enrich agri-food products with probiotics. Among the probiotics, recent studies focused on Lactiplantibacillus plantarum, Lactobacillus brevis, Lactococcus lactis, Lactobacillus casei, Leuconostoc mesenteroides, Bifidobacteria. These bacteria proliferated in the log phase when treated with US at relatively low-intensities. Also, this non-thermal technology increased extracellular enzymes, mainly β-galactosidase, and effectively extracted antioxidants and bioactive compounds such as phenolics, flavonoids, and anthocyanins. Accordingly, better functional and physicochemical properties of prebiotic-based foods (e.g., fermented dairy products) can be expected after ultrasonication at appropriate conditions. Besides, the US improved fermentation efficiency by reducing the production time, making probiotics more viable with lower lactose content, more oligosaccharide, and reduced unpleasant taste. Also, US can enhance the rheological characteristics of probiotic-based food by altering the acidity. Optimizing US settings is suggested to preserve probiotics viability to achieve high-quality food production and contribute to food nutrition improvement and sustainable food manufacturing.

The nutritional value, bioactive availability and functional properties of garlic and its related products during processing

Garlic, a common culinary spice, is cultivated and used around the globe. Consumption of garlic and its supplements reduces the risk of diabetes and cardiovascular disease and boosts the immune system with antibacterial, antifungal, anti-aging, and anti-cancer properties. Diallyl sulfide, diallyl disulfide, triallyl trisulfide, phenolics, flavonoids, and others are the most commercially recognized active ingredients in garlic and its products. In recent years, global demand for medicinal or functional garlic has surged, introducing several products such as garlic oil, aged garlic, black garlic, and inulin into the market. Garlic processing has been demonstrated to directly impact the availability of bioactive ingredients and the functionality of products. Depending on the anticipated functional qualities, it is also recommended that one or a combination of processing techniques be deemed desirable over the others. This work describes the steps involved in processing fresh garlic into products and their physicochemical alterations during processing. Their nutritional, phytochemical, and functional properties are also reviewed. Considering the high demand for functional food, this review has been compiled to provide guidance for food producers on the industrial utilization and suitability of garlic for new product development.

Faba Bean Processing: Thermal and Non-Thermal Processing on Chemical, Antinutritional Factors, and Pharmacological Properties

The food industry, academia, food technologists, and consumers have become more interested in using faba bean seeds in the formulation of new products because of their nutritional content, accessibility, low costs, environmental advantages, and beneficial impacts on health. In this review, a systematic and up-to-date report on faba bean seeds' antinutrients and bioactive and processing techniques is comprehensively presented. The chemical composition, including the oil composition and carbohydrate constituents, is discussed. Factors influencing the reduction of antinutrients and improvement of bioactive compounds, including processing techniques, are discussed. Thermal treatments (cooking, autoclaving, extrusion, microwaving, high-pressure processing, irradiation) and non-thermal treatments (soaking, germination, extraction, fermentation, and enzymatic treatment) are identified as methods to reduce the levels of antinutrients in faba bean seeds. Appropriate processing methods can reduce the antinutritional factors and enrich the bioactive components, which is useful for the seeds' efficient utilization in developing functional foods. As a result, this evaluation focuses on the technologies that are employed to reduce the amounts of toxins in faba bean seeds. Additionally, a comparison of these methods is performed in terms of their advantages, disadvantages, viability, pharmacological activity, and potential for improvement using emerging technologies. Future research is expected in this area to fill the knowledge gap in exploiting the nutritional and health benefits of faba bean seeds and increase the utilization of faba bean seeds for different applications.

Potential of Syzygnium polyanthum as Natural Food Preservative: A Review

Food preservation is one of the strategies taken to maintain the level of public health. Oxidation activity and microbial contamination are the primary causes of food spoilage. For health reasons, people prefer natural preservatives over synthetic ones. Syzygnium polyanthum is widely spread throughout Asia and is utilized as a spice by the community. S. polyanthum has been found to be rich in phenols, hydroquinones, tannins, and flavonoids, which are potential antioxidants and antimicrobial agents. Consequently, S. polyanthum presents a tremendous opportunity as a natural preservative. This paper reviews recent articles about S. polyanthum dating back to the year 2000. This review summarizes the findings of natural compounds presented in S. polyanthum and their functional properties as antioxidants, antimicrobial agents, and natural preservatives in various types of food.

The influence of non-thermal technologies on color pigments of food materials: An updated review

The color of any food is influenced by several factors, such as food attributes (presence of pigments, maturity, and variety), processing methods, packaging, and storage conditions. Thus, measuring the color profile of food can be used to control the quality of food and examine the changes in chemical composition. With the advent of non-thermal processing techniques and their growing significance in the industry, there is a demand to understand the effects of these technologies on various quality attributes, including color. This paper reviews the effects of novel, non-thermal processing technologies on the color attributes of processed food and the implications on consumer acceptability. The recent developments in this context and a discussion on color systems and various color measurement techniques are also included. The novel non-thermal techniques, including high-pressure processing, pulsed electric field, ultrasonication, and irradiation which employ low processing temperatures for a short period, have been found effective. Since food products are processed at ambient temperature by subjecting them to non-thermal treatment for a very short time, there is no possibility of damage to heat-sensitive nutrient components in the food, any deterioration in the texture of the food, and any toxic compounds in the food due to heat. These techniques not only yield higher nutritional quality but are also observed to maintain better color attributes. However, suppose foods are exposed to prolonged exposure or processed at a higher intensity. In that case, these non-thermal technologies can cause undesirable changes in food, such as oxidation of lipids and loss of color and flavor. Developing equipment for batch food processing using non-thermal technology, understanding the appropriate mechanisms, developing processing standards using non-thermal processes, and clarifying consumer myths and misconceptions about these technologies will help promote non-thermal technologies in the food industry.

The effects of pulsed electric fields treatment on the structure and physicochemical properties of dialdehyde starch

The structural and physicochemical properties changes of corn starch oxidized by sodium periodate under the assistance of pulsed electric fields (PEF) were studied. It was found that dialdehyde starch (DAS) particles produced by PEF-assisted oxidation exhibited shrinkage and pits, and had a larger particle size when compared to the control without PEF. The solubility of the DAS (12 kV/cm PEF- assisted oxidation) improved by 70.2% when compared to the native starch. Increment in the strength of the PEF, led to a decrease in the viscosity of the DAS. In addition, the aldehyde group content of the DAS produced by PEF-assisted oxidation exhibited shrinkage and pits, and had a larger particle size when compared to the control increased by 11.6% when compared with the traditional oxidation method. PEF is an effective method to promote oxidation reaction of starch.

Recent and novel processing technologies coupled with enzymatic hydrolysis to enhance the production of antioxidant peptides from food proteins: A review

Antioxidant peptides obtained through enzymatic hydrolysis of food proteins exhibit a broad range of bioactivities both in vitro and in vivo models. The antioxidant peptides showed the potential to fight against the reactive oxygen species, free radicals and other pro-oxidative substances which are considered the source of various chronic diseases for humans. Both animals and plants have been recognized as natural protein sources and attracted much research interest over the synthetic ones in terms of safety. However, the main challenge remains to increase the antioxidant peptides yield, reduce the enzyme quantity and the reaction time. Consequently, different efficient and innovative food processing technologies such as thermal, ultrasound, microwave, high hydrostatic pressure, pulsed electric field, etc. have been developed and currently used to treat food proteins before (pretreatment) or during the enzymatic hydrolysis (assisted). Those technologies were found to significantly enhance the degree of hydrolysis and the production of substantial antioxidant peptides. These emerging technologies enhance the enzymatic hydrolysis by inducing protein denaturation/unfolding, and the enzymatic activation without altering their functional and nutritional properties. This review discusses the state of the art of thermal, ultrasound, high hydrostatic pressure, microwave, and pulsed electric field techniques, their applications while coupled with enzymatic hydrolysis, their comparison and potential challenges for the production of antioxidant peptides from food proteins.

Physical treatment synergized with natural surfactant for improving gas-water interfacial behavior and foam characteristics of α-lactalbumin

The purpose of this study was to investigate effect of physical treatment (ultrasound, U/high pressure homogenization, H/combined treatment, UH or HU) and surfactant (Mogroside V, Mog) on air/water interface adsorption and foaming properties of α-lactalbumin (ALa). Firstly, the binding of Mog and all physical-treated ALa was a static quenching process. Mog had the greatest binding affinity for HU-ALa among all treated samples. U or H treatment could change surface hydrophobicity of ALa/Mog complex. Secondly, at the molar ratio (ALa:Mog) of 1:50, foaming ability (FA) of all ALa samples got the maximum. The sequence of FA in ALa and ALa/Mog complex was listed as follow: HU > U > H > UH. Moreover, foaming stability (FS) of HU-ALa was the highest, followed by H-ALa, U-ALa and UH-ALa. Meanwhile, low concentration Mog increased FS of ALa or UH-ALa, but it reduced FS of H-ALa, U-ALa and HU-ALa. Quartz crystal microbalance with dissipation monitoring (QCM-D) experiment indicated that ALa/Mog complex after U or H treatment was quickly absorbed at air/water interface, compared with the treated ALa, and HU-ALa/Mog had the largest frequency shift. In addition, HU-ALa had the thickest bubble membrane and the highest dissipation shift in all samples, indicating that the absorbed membrane thickness and viscoelasticity of samples was correlated with foam stability. Therefore, U and H treatment synergism with Mog was an effective approach to enhance foam properties of ALa, which indicated that HU-treated ALa/Mog complex could be viewed as the safe and efficient foaming agent applied in food processing.

Effects of Different Blanching Methods on the Quality of Tremella fuciformis and Its Moisture Migration Characteristics

Blanching is a critical step in the processing of Tremella fuciformis (T. fuciformis). The effects of different blanching methods (boiling water blanching (BWB), ultrasonic-low temperature blanching (ULTB), and high-temperature steam (HTS)) on the quality and moisture migration characteristics of T. fuciformis were investigated. The results showed that the T. fuciformis blanched by ULTB (70 °C, 2 min, 40 kHz, 300 W) had the best quality, including a brighter appearance, superior texture, and good sensory features, with a polysaccharide content of 3.90 ± 0.02%. The moisture migration characteristics of T. fuciformis after blanching exhibited four peaks, displayed strong and weak chemically bound water, immobilized water, and free water, whereas ULTB had a weak effect on the freedom of water in T. fuciformis. The study will provide the foundation for the factory processing of T. fuciformis.

Effects of Low-Frequency Electromagnetic Field on the Physicochemical Properties of Freeze-Thawed Mongolian Cheese

To verify whether a low-frequency electromagnetic field (LFE field) can help reduce structural damage during the freeze-thaw process and maintain shelf life, Mongolian cheese was frozen at -10, -20, and -30 °C, then thawed at microwave or room temperature. Results showed that LFE field-assisted frozen treatment could reduce ice crystal size and protect the protein matrix structure of cheese. Frozen-thawed cheese retained 96.5% of its hardness and showed no significant difference from the fresh one in elasticity, cohesion, and chewiness. Frozen cheese showed similar but slower ripening behavior during storage, suggesting a potential application of the LFE field in the frozen storage of high-protein foods.

Combining pulsed electric field and cross-linking to enhance the structural and physicochemical properties of corn porous starch

In this study, corn porous starch (CPS) was firstly prepared using enzymatic hydrolysis, followed by pore formation enhancement using the treatment of a pulsed electric field (PEF). Subsequently, the PEF treated porous starch (CPS-PEF) was cross-linked with sodium trimetaphosphate (STMP) to investigate its structural and functional properties. The results showed PEF treatment increased the oil absorption of CPS by 26.92% and improved its specific surface area, total pore volume value, solubility and swelling power. After cross-linking of the CPS-PEF, C-O-P covalent bonds were formed between CPS-PEF molecules, resulting in a further increase in oil absorption and specific surface area properties. Moreover, the covalent bonds enhanced the intermolecular forces, resulting in increased thermal stability of the cross-linked porous starch (ScPS). The double modification resulted in significantly improved adsorption properties and better thermal stability of the ScPS, indicating that the double modification is an effective method for the preparation of porous starches.

Pulsed electric field-assisted esterification improves the freeze-thaw stability of corn starch gel by changing its molecular structure

The influence of pulsed electric field (PEF) combined with octenyl succinic anhydride (OSA) on the freeze-thaw stability of corn starch gel was investigated. After five freeze-thaw cycles, the syneresis value of OSA starch treated with PEF-assisted esterification for 15 min was lower by 29.5 %, while that of OSA starch without PEF treatment was lower by 10.17 %, compared to that of native starch. Low-field nuclear magnetic resonance data showed that the introduction of OSA groups greatly increased the water-holding capacity of starch. Results from differential scanning calorimetry (DSC) and X-ray diffraction (XRD) showed that the PEF-assisted esterification markedly hindered the re-formation of the helical structure of starch during freeze-thaw cycles. Moreover, PEF-assisted esterification improved the viscoelastic properties of the starch gel. It is found that the freeze-thaw stability of the PEF-modified starch depends not only on the degree of substitution but also on the starch molecular fine structure. PEF-assisted OSA starch with a high degree of substitution, a low content of amylose, and a high content of short amylopectin chains were found to have high freeze-thaw stability. This study shows that PEF-assisted esterification is a promising technique that should be used for preserving the quality of frozen foods.

The impact of cold plasma innovative technology on quality and safety of refrigerated hamburger: Analysis of microbial safety and physicochemical properties

Atmospheric cold plasma (ACP) is an innovative non-thermal decontamination technology that is considered a great alternative to conventional preservation methods. Most importantly, improving microbial safety along with maintaining the sensory and quality properties of the treated foods, especially for perishable products. Hence, this study aimed to investigate the antimicrobial effects of novel dielectric barrier discharge (DBD) and Jet cold plasma systems and their impact on the physicochemical, color, and sensory properties of refrigerated hamburger samples. In the current study, hamburger samples were inoculated with Staphylococcus aureus, Escherichia coli, Molds and Yeasts microbial suspension (~10⁶ CFU/mL), and then were treated with argon (Ar), helium (He), nitrogen (N), and atmosphere (Atm) gases at different times (s) (0, 30, 60, 90, 180, 360). Similarly, uninoculated samples were considered for total viable count (TVC) testing. The results exhibited that plasma system type, gas type, and treatment time had a significant antimicrobial effect with a microbial reduction ranging from 0.01 to 2 log CFU/g and 0.04-1.5 log CFU/g for DBD and Jet plasma systems, respectively. Also, a treatment time longer than 90 s for DBD and 180 s for jet resulted in a significant reduction in microbial count. The ability of atmospheric cold plasma to inactivate tested foodborne pathogenic bacteria (E. coli and S. aureus) was stronger than other gases because the concentration of O₃ and NO gases in atmospheric plasma is higher than other used plasma gases. Surface color measurements (L*, a* and b*) of samples in both methods (DBD and Jet) were not significantly affected. Moreover, samples treated with various plasma gases have indicated insignificant oxidation changes (Thiobarbituric acid assay). These outcomes can assist to reduce microbial contamination and oxidation of hamburgers as a high-consumption and perishable product using ACP technology. Owing to the non-thermal nature of ACP, samples treated with ACP have exhibited no or least effects on the physical, chemical, and sensory features of various food products. As a result, cold plasma innovative technology can be proposed and used as an efficient preservative method to increase the shelf life of food products.

A Systematic Quantitative Determination of the Antimicrobial Efficacy of Grape Seed Extract against Foodborne Bacterial Pathogens

Concerns regarding the role of antimicrobial resistance (AMR) in disease outbreaks are growing due to the excessive use of antibiotics. Moreover, consumers are demanding food products that are minimally processed and produced in a sustainable way, without the use of chemical preservatives or antibiotics. Grape seed extract (GSE) is isolated from wine industry waste and is an interesting source of natural antimicrobials, especially when aiming to increase sustainable processing. The aim of this study was to obtain a systematic understanding of the microbial inactivation efficacy/potential of GSE against Listeria monocytogenes (Gram-positive), Escherichia coli and Salmonella Typhimurium (Gram-negative) in an in vitro model system. More specifically, for L. monocytogenes, the effects of the initial inoculum concentration, bacterial growth phase and absence of the environmental stress response regulon (SigB) on the GSE microbial inactivation potential were investigated. In general, GSE was found to be highly effective at inactivating L. monocytogenes, with higher inactivation achieved for higher GSE concentrations and lower initial inoculum levels. Generally, stationary phase cells were more resistant/tolerant to GSE as compared to exponential phase cells (for the same inoculum level). Additionally, SigB appears to play an important role in the resistance of L. monocytogenes to GSE. The Gram-negative bacteria under study (E. coli and S. Typhimurium) were less susceptible to GSE as compared to L. monocytogenes. Our findings provide a quantitative and mechanistic understanding of the impact of GSE on the microbial dynamics of foodborne pathogens, assisting in the more systematic design of natural antimicrobial-based strategies for sustainable food safety.

The microstructure and thermal properties of pulsed electric field pretreated oxidized starch

The structure and thermal properties of pulsed electric field (PEF) assisted sodium hypochlorite oxidized starch were investigated. The carboxyl content of the oxidized starch was increased by 25 % when compared with the traditional oxidation method. Dents and cracks were evident on the surface of the PEF-pretreated starch. Compared with native starch, the peak gelatinization temperature (T_p) of PEF-assisted oxidized starch (POS) was reduced by 10.3 °C, while that of the oxidized starch without PEF treatment (NOS) was only reduced by 7.4 °C. In addition, PEF treatment further reduces the viscosity and improve the thermal stability of the starch slurry. Therefore, PEF treatment combined with hypochlorite oxidation is an effective method to prepare oxidized starch. PEF showed great potential in expanding starch modification, to promote a wider application of oxidized starch in the paper, the textile and the food industry.

Inactivation of Alicyclobacillus acidoterrestris spores, single or composite Escherichia coli and native microbiota in isotonic fruit-flavoured sports drinks processed by UV-C light

Pasteurized sports drinks and other fruit-based beverages are susceptible to deterioration due to thermal processing ineffectiveness to inactivate certain spoilage microorganisms, like Alicyclobacillus acidoterrestris. This represents a major challenge for the beverage industry. The goals of this study were to: i) investigate the UV-C inactivation (annular thin film unit, actinometrical delivered fluence: 795-1270 mJ/cm², 10-15 min, 20 °C, 1.8 L/h, Re_h = 391-1067, recirculation mode operation) and the evolution during refrigerated storage of A. acidoterrestris ATCC 49025 spores and single or composite Escherichia coli ATCC 25922 in isotonic sports drinks (ISDs) made from orange (orange-ISD, UVT% = 81) or orange-banana-mango-kiwi-strawberry-lemon juices (multi-fruit-ISD, UVT% = 91), compared to a turbid orange-tangerine juice (OT juice, UVT% = 40); ii) assess the effect of pH, °Brix, A_254nm, turbidity, colour and particle size of the ISDs and juice on microbial inactivation, iii) evaluate the evolution of native microbiota during cold storage, iv) investigate the Coroller, biphasic, Weibull, and Weibull-plus-tail models' ability to describe microbial inactivation and v) measure 5-hydroxymethylfurfural (HMF) formation. The modified biodosimetry method was used to calculate the germicidal UV-C fluences. Heat pasteurization (T-coil, 80 °C/6 min) was evaluated as the control treatment. UV-C was highly effective at inactivating E. coli as 4.1-5.1 and 4.5-5.6 log reductions were determined in the multi-fruit-ISD and orange-ISD, respectively, barely impacted by the background microbiota. No significant differences were recorded for the inactivation of E. coli in the UV-C and T-coil systems. Whereas, a significantly higher inactivation of A. acidoterrestris spores was achieved by UV-C (3.7-4.0 log reductions), compared to the negligible one achieved by the thermal treatment. Even though E. coli inactivation curves were similar in shape, UV-C was less effective when a cocktail of other E. coli strains was present. In comparison to the OT juice, the ISDs' inactivation kinetics were markedly different in shape, with a rapid decrease in population during the first minutes of treatment. The germicidal fluence (H_{d biod}) corresponding to A. acidoterrestris (19.1 mJ/cm²) was selected as it was higher than the one obtained for E. coli (11.0 mJ/cm²). UV-C induced 2.8- or 1.3 and 2.3- or 0.8 log-reductions of total aerobes or moulds and yeasts in the multi-fruit-ISD and orange-ISD, respectively. Compared to the other models, the Coroller and biphasic models showed a better fit and more accurate parameter estimates. UV-C-induced HMF production was not significant in the ISDs. The current study found that the UV-C treatment was more effective than typical heat pasteurization for inactivating A. acidoterrestris spores in isotonic drinks, following a similar trend for E. coli and native microbiota.

Constructing Selenium Nanoparticles with Enhanced Storage Stability and Antioxidant Activities via Conformational Transition of Curdlan

Selenium nanoparticles (SeNPs) are among the emerging selenium supplements because of their high bioactivity and low toxicity. However, bare SeNPs are prone to activity loss caused by aggregation and sedimentation. This study aims to stabilize SeNPs with curdlan (CUR), a polysaccharide, to maintain or even enhance their biological activity. Herein, the stable SeNPs were constructed via the unique conformational transition of CUR induced by alkali-neutralization (AN) pretreatment. The physicochemical properties and structures of the prepared SeNPs were characterized by dynamic light scattering (DLS), UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and free-radical-scavenging activity assays. The results show that most SeNPs are stabilized within the triple helix of CUR that has been pretreated with high-intensity AN treatment. These amorphous, small-sized (average size was 53.6 ± 17.7 nm), and stabilized SeNPs have significantly enhanced free-radical-scavenging ability compared to the control and can be well-stabilized for at least 240 days at 4 °C. This work indicates that CUR, as a food additive, can be used to well-stabilize SeNPs by AN pretreatment and provides a facile method to prepare and enhance the stability and bioactivity of SeNPs via triple-helix conformational transition.

Dynamic alterations in protein, sensory, chemical, and oxidative properties occurring in meat during thermal and non-thermal processing techniques: A comprehensive review

Meat processing represents an inevitable part of meat and meat products preparation for human consumption. Both thermal and non-thermal processing techniques, both commercial and domestic, are able to induce chemical and muscle's proteins modification which can have implication on oxidative and sensory meat characteristics. Consumers' necessity for minimally processed foods has paved a successful way to unprecedented exploration into various novel non-thermal food processing techniques. Processing of meat can have serious implications on its nutritional profile and digestibility of meat proteins in the digestive system. A plethora of food processing techniques can potentially induce alterations in the protein structure, palatability, bioavailability and digestibility via various phenomena predominantly denaturation and Maillard reaction. Apart from these, sensory attributes such as color, crispness, hardness, and total acceptance get adversely affected during various thermal treatments in meat. A major incentive in the adoption of non-thermal food processing is its energy efficiency. Considering this, several non-thermal processing techniques have been developed for evading the effects of conventional thermal treatments on food materials with respect to Maillard reactions, color changes, and off-flavor development. Few significant non-thermal processing techniques, such as microwave heating, comminution, and enzyme addition can positively affect protein digestibility as well as enhance the value of the final product. Furthermore, ultrasound, irradiation, high-pressure processing, and pulsed electric fields are other pivotal non-thermal food processing technologies in meat and meat-related products. The present review examines how different thermal and non-thermal processing techniques, such as sous-vide, microwave, stewing, roasting, boiling, frying, grilling, and steam cooking, affect meat proteins, chemical composition, oxidation, and sensory profile.

Effectiveness of a Phage Cocktail as a Potential Biocontrol Agent against Saprophytic Bacteria in Ready-To-Eat Plant-Based Food

This study aimed to evaluate the effectiveness of the phage cocktail to improve the microbiological quality of five different mixed-leaf salads: rucola, mixed-leaf salad with carrot, mixed-leaf salad with beetroot, washed and unwashed spinach, during storage in refrigerated conditions. Enterobacterales rods constituted a significant group of bacteria in the tested products. Selected bacteria were tested for antibiotic resistance profiles and then used to search for specific bacteriophages. Forty-three phages targeting bacteria dominant in mixed-leaf salads were isolated from sewage. Their titer was determined, and lytic activity was assessed using the Bioscreen C Pro automated growth analyzer. Two methods of phage cocktail application including spraying, and an absorption pad were effective for rucola, mixed leaf salad with carrot, and mixed leaf salad with beetroot. The maximum reduction level after 48 h of incubation reached 99.9% compared to the control sample. In washed and unwashed spinach, attempts to reduce the number of microorganisms did not bring the desired effect. The decrease in bacteria count in the lettuce mixes depended on the composition of the autochthonous saprophytic bacteria species. Both phage cocktail application methods effectively improved the microbiological quality of minimally processed products. Whole-spectral phage cocktail application may constitute an alternative food microbiological quality improvement method without affecting food properties.

Variation in physicochemical properties and bioactivities of Morinda citrifolia L. (Noni) polysaccharides at different stages of maturity

Introduction

Morinda citrifolia L. (Noni) as an evergreen plant is a rich source of natural polysaccharides.

Objective

The present work aims to investigate the maturation-related changes in polysaccharides of Morinda citrifolia L. (Noni) at five stages of maturity (stages from the lowest to highest degree - 1, 2, 3, 4, and 5).

Methods

The chemical composition (carbohydrate, protein, uronic acid, and sulfate radical) of Noni polysaccharides was determined by different chemical assays. Ion chromatography system was used to analyze the monosaccharide composition, and the molecular weight was measured by HPGPC. The polysaccharides were also analyzed by FT-IR and their radical scavenging effect against DPPH, hydroxyl radicals and ABTS was evaluated. The UV-vis assay and gel electrophoresis assay were performed to investigate the DNA damage protective effect.

Results

Results indicated the significant effect of fruit maturities on the extraction yields, molecular weights, uronic acid contents, sugar levels, monosaccharide compositions and proportions, antioxidant capacities, and DNA protective effects of Noni polysaccharides. However, no fruit maturity stage had prominent impact on the sulfuric radical contents and preliminary structure characteristics. Noni polysaccharides extracted at stage 5 (N5) had the largest extraction yield (8.26 ± 0.14%), the highest sugar content (61.94 ± 1.86%) and the most potent scavenging effect on DPPH (IC₅₀: 1.06 mg/mL) and ABTS (IC₅₀: 1.22 mg/mL) radicals. The stronger DPPH and ABTS radical scavenging activities of N5 might be contributed by its higher content of fucose and rhamnose and smaller molecular weight. Noni polysaccharides extracted at stage 4 (N4) showed the highest uronic acid content (4.10 ± 0.12%), and the superior performance in scavenging hydroxyl radicals and protecting DNA. The greater hydroxyl radical scavenging effect of N4 might be attributed to its higher percentage of the low molecular weight counterpart. Moreover, the DNA protective effects of N4 displayed a positive correlation with its hydroxyl radical scavenging ability.

Conclusion

Overall, stage 4 and stage 5 could be ideal stages of fruit maturity aiming at high-quality Noni polysaccharides extraction. This study provided valuable information for the selection of suitable Noni polysaccharides to cater for various industrial applications.

Recent Insights on the Role of Various Food Processing Operations Towards the Development of Sustainable Food Systems

Chronic hunger and malnutrition will eventually result from the population's rapid growth. It is unlikely to succeed in tackling the rising challenges of delivering sustainable food for all people unless high attention is paid on the function of food processing to ensure the supply of stable food. It is impossible to overstate the importance of developing food processing and preservation technologies that can reduce food losses and wastage during surplus seasons. Therefore, sustainable food systems must be developed to provide healthy diets without damaging our world and its resources. The goal is to use various perspectives to confirm why food processing is crucial to future food supply. It is important to show the appropriate utilization of sustainability factors and effect assessments to construct for feeding the globe while staying within planetary limits. There has never been a better time to assure a plentiful food supply to feed the people than right now, when the population is expanding at a worrying rate. The sustainable food project seeks to move the food systems in a long-term, more equitable direction. Food processing, or the conversion of raw materials into functional, edible, and consumer acceptable food, is a critical link in the food value chain between consumption and production. This review looked at various existing and emerging food processing followed by preservation techniques. Food systems must also attempt to reduce food waste and losses, as well as the current and future impacts on the environment and society, to be sustainable.