Quality considerations with high pressure processing of fresh and value added meat products

Methods of Controlling Microbial Contamination of Food

The rapid growth of world population and increase in living standards have led to an increase in the demand for high-quality, safe food. The Food and Agriculture Organization of the United Nations (FAO) estimates that by 2050 the demand for food will increase by 60%, and production of animal protein will increase by 1.7% a year, with meat production to increase by nearly 70%, dairy products by 55%, and aquaculture by as much as 90%. Microbial contamination of food is a significant problem for the accessibility of safe food which does not pose a threat to the life and health of consumers. Campylobacter, Salmonella, and Yersinia are responsible for thousands of food-borne infections in humans. Currently, numerous programs are being developed to combat pathogenic bacteria in the food supply chain, especially at the primary production stage. These approaches include physical, chemical, biological, and other strategies and methods used to inhibit the bacterial growth of bacteria or completely eliminate the pathogens from the food chain. Therefore, an extremely important goal is to provide safe food and control its quality by eliminating pathogenic and spoilage microorganisms. However, the use of chemicals in food preservation has negative effects for both the consumption values of food and the natural environment. Therefore, it seems absolutely necessary to implement measures utilizing the most environmentally friendly and effective techniques for controlling microbial contamination in food. There is a great need to develop ecological methods in food production which guarantee adequate safety. One of these methods is the use of bacteriophages (bacterial viruses) naturally occurring in the environment. Given the above, the aim of this study was to present the most natural, ecological, and alternative methods of food preservation with regard to the most common foodborne zoonotic bacteria. We also present methods for reducing the occurrence of microbial contamination in food, thus to produce maximally safe food for consumers.

Enhancing Shelf Life and Nutritional Quality of Lamb Burgers with Brassica By-Products: A Synergistic Approach Using High Hydrostatic Pressure

This study examines the effects of incorporating broccoli and cauliflower by-products (leaves, stems and inflorescences) like puree ingredients and applying high hydrostatic pressure (HHP) treatment on the quality, safety, and shelf life of lamb burgers. Broccoli and cauliflower by-products were valorized like rich bioactive ingredients, especially in phenol compounds. The valorized ingredients were added to lamb burgers (5% w/w), and 120 burgers were produced for the experiment: three formulations (lamb, lamb with broccoli, and lamb with cauliflower) × four pressure treatments (untreated, 400 MPa, 500 MPa, 600 MPa) × five replicates per formulation and pressure treatment × two storage times (day 1 and day 14). The interactions between composition and pressure were also investigated. The results indicated that while Brassica by-products contributed to slight changes in moisture content and fatty acid composition, they did not independently provide strong antimicrobial effects, likely due to their high moisture content and minimal impact on pH reduction. However, combining these ingredients with HHP treatment (600 MPa for 60 s) significantly improved microbial stability. HHP treatment effectively reduced microbial counts, which were maintained during refrigerated storage, supporting its role as a valuable non-thermal intervention for enhancing meat safety. In terms of oxidative stability, the inclusion of Brassica ingredients, particularly with HHP, reduced lipid (TBA-RS ≤ 1.47 MDA mg kg-1) and protein oxidation (≤5.05 Nmol mg-1 proteins) over time, thereby enhancing product stability during storage. Sensory evaluation and affective testing revealed no significant differences in appearance, odor, taste, texture, or overall acceptability between treated and untreated samples, with high acceptance scores. This suggests that HHP treatment, in combination with Brassica by-products, can improve safety and oxidative stability without compromising the sensory quality of meat products. Overall, this study presents a sustainable and effective approach for producing high-quality and safe meat products with extended shelf life.

Reheating-induced gel properties change and flavor evolution of surimi-based seafood: Effects and mechanisms

This study investigated the effect of different reheating treatments on gel properties and flavor changes of surimi products. As the reheating temperature increased from 90 °C to 121 °C, the heat-induced proteolysis produced more abundant umami and sweet amino acids, which took part in the conversion of IMP to AMP, thus enhancing the taste profiles. Reheating increased the exposure of active -NH2 terminals in proteins, which boosted Maillard and Strecker reactions with carbonyl compounds originated from fatty acid oxidation, thus not only reducing the aldehydes and esters contents but also lowering the whiteness of surimi products. Reheating at 90 °C prohibited the production of warmed-over flavor (WOF) and well-preserved the textural characteristics, but high temperatures ≥100 °C were prone to generate furan as the major WOF substance and to destroy gel structures. Collectively, this study provides new insights on understanding the role of reheating on sensory properties of surimi products.

Thermal-assisted pressure processing: effects of marination, temperature, and pressure level on physicochemical, color and textural parameters of Superficial pectoralis beef muscle

This study aimed to evaluate the effects of salt addition and different thermal-assisted pressure processing (TAPP) conditions (temperature and pressure levels) on technological, chromatic, and textural parameters and lipid oxidation of Superficial pectoralis beef muscle. A factorial design with three factors was applied: KCl/NaCl marination (marinated samples MS; non-marinated samples, NMS), temperature during high-pressure processing (50, 70°C), and pressure level (0.1, 200, and 300 MPa). All factors affect the water-holding capacity of beef, which is important to ensure both high yields and optimal tenderness and juiciness in the final product. MS treated at 50°C had the highest yield values, regardless of applied pressure level. TAPP modified the color parameter values of raw samples, resulting in brighter and less reddish. After cooking, color differences remained, indicating that this process did not fully reverse the changes induced by TAPP treatments. MS had lower shear force values than NMS. The presence of salts slightly diminished shear force values. A similar texture profile was obtained for NMS treated at 70°C and 300 MPa and MS treated at 50°C and 200 MPa. NMS and MS treated at 70°C and 0.1 MPa had the highest thiobarbituric acid reactive substance values. Based on the results, marinated samples treated at 200 MPa and 50°C were selected for treatment. TAPP could be an innovative technology for the development of value-added beef products with assured texture. PRACTICAL APPLICATION: Beef tenderness is an essential attribute in consumer satisfaction and purchase decisions. However, several factors affect tenderness, such as the amount of connective tissue, muscle contraction in rigor mortis, and proteolysis. The development of ready-to-cook products with guaranteed tenderness by applying thermally assisted pressure processing would benefit both the industry and consumers.

Oxidative regulation and cytoprotective effects of γ-polyglutamic acid on surimi sol subjected to freeze-thaw process

Frozen surimi sol incline to protein oxidation, but the quality control strategies based on oxidation remain limited. Hence, the antioxidant and cryoprotective effects of γ-polyglutamic acid (γ-PGA) on freeze-thawed salt-dissolved myofibrillar protein (MP) sol were investigated. Results showed that γ-PGA could effectively regulate protein oxidation of MP sol during freeze-thawing with lower carbonyl contents and less oxidative cross-linking. Meanwhile, γ-PGA primely maintained sol protein structures, showing reduction of 15.28% of salt soluble protein contents at γ-PGA addition of 0.04% under unoxidized condition. Additionally, compared to the control group without oxidation treatment, cooking loss of heat-induced gel with 0.04% γ-PGA decreased by 47.19%, while gel strength obviously increased by 57.22% respectively. Overall, moderate γ-PGA addition (0.04%) could inhibit protein oxidation of sol, further improving frozen stability of sol through hydrogen bonds and hydrophobic interaction, but excessive γ-PGA was adverse to sol quality due to severe cross-linking between γ-PGA and MP.

The Influence of High Hydrostatic Pressure on Selected Quality Features of Cold-Storage Pork Semimembranosus Muscle

The primary objective of this investigation was to assess the influence of high hydrostatic pressure (HHP) and the duration of cold storage on the physicochemical, technological, and sensory attributes as well as the nutritional composition and shelf life of meat. The experimental framework involved utilizing samples derived from the semimembranosus muscle of pork. Each muscle obtained from the same carcass was segmented into six distinct parts, with three designated as control specimens (K) and the remaining subjected to vacuum packaging and subsequent exposure to high hydrostatic pressure (200 MPa at 20 °C for 30 min). Comprehensive laboratory analyses of the meat were conducted at 1, 7, and 10 days post slaughter. The meat was cold-stored at +3 ± 0.5 °C. The findings of the study elucidated that the application of high hydrostatic pressure exhibited a favorable impact on the extension of the raw meat's shelf life. The tests showed a significant (p < 0.05) decrease in the total number of microorganisms compared to the control sample after 7 (K: 4.09 × 105, HHP: 2.88 × 105 CFU/g) and 10 (K: 7.40 × 105, HHP: 2.42 × 105 CFU/g) days of cold storage. It was also found that using HHP increased the pH value after 1 (K: 5.54, HHP: 5.77) and 7 (K: 5.60, HHP: 5.87) days of storage.

The effect of ohmic heating conditions and heating modes on gel properties of unwashed pre-rigor common carp (Cyprinus carpio) surimi

Ohmic heating (OH) at different conditions (voltage: 15, 20, 25 V; frequency: 1, 5, 10 kHz) and one-step water bath (WB) were used to heat wash and unwash surimi prepared from fresh pre-rigor common carp. The optimal heating conditions were established through assessments of gel strength, Texture Profile Analysis (TPA), water-holding capacity (WHC), whiteness, and sensory evaluation. Then, the impact of heating modes on gelation properties of unwashed surimi based on the optimal heating conditions was investigated. The study findings indicated a significant enhancement in gel properties compared to WB. Unwashed surimi gel properties showed improvement when derived from freshly caught raw fish and subjected to OH treatment. Moreover, variations in frequencies and voltages were observed to influence the heating rate. Optimal gel quality was achieved at 10 kHz 20 V (10 V/cm), facilitating swift progression through the gel deterioration stage, inhibition of protein hydrolyzing enzymes activity, and establishment of a stable gel network. Continuing to increase the heating rate would disrupt its network structure, resulting in diminished gel strength and WHC. The best quality of unwashed surimi gel was achieved by heating to 40°C for 30 min, followed by heating to 90°C for another 30 min (40°C 30 min + 90°C 30 min) under 10 kHz 20 V. The gel strength increased when held for 1 h at 40°C. For optimal heating efficiency, the heating mode of 40°C 30 min + 90°C 30 min is recommended to prepare unwashed surimi gel. PRACTICAL APPLICATION: Ohmic heating, as a rapid food heat treatment method, can both increase the heating rate and improve the gelation properties of freshwater surimi. There is a wide range of potential applications for the heat treatment of the surimi.

Physical property changes promoting shelf-life extension of soy protein-based high moisture meat analog under high pressure treatment

The effects of high pressure treatment were investigated on the physical properties and possible shelf-life extension of soy protein-based high moisture meat analog (S-HMMA) produced by the extrusion process. High pressure treatment was applied at 200, 400 and 600 MPa for 5, 10 and 15 min. Physical properties of S-HMMA including appearance, moisture content, color and texture were analyzed during storage at 4 °C for 8 weeks. Higher pressure and longer storage time significantly reduced moisture content by creating more air cells and increasing cavitation. L* value of S-HMMA products increased at higher levels of pressurization while increasing storage time tended to decrease lightness. The unpressurized control S-HMMA product showed increasing hardness and toughness, while S-HMMA products subjected to various pressures exhibited higher hardness and toughness over time compared to the control sample at 200-400 MPa. Products treated with high pressure (600 MPa) showed the highest reductions in microbial growth but the aroma of the beans became more pronounced.

A review of the world's salt reduction policies and strategies - preparing for the upcoming year 2025

Excessive consumption of dietary sodium is a significant contributor to non-communicable diseases, including hypertension and cardiovascular disease. There is now a global consensus that regulating salt intake is among the most cost-effective measures for enhancing public health. More than half of the countries worldwide have implemented multiple strategies to decrease salt consumption. Nevertheless, a report on sodium intake reduction published by the World Health Organization revealed that the world is off-track to meet its targeted reduction of 30% by 2025. The global situation regarding salt reduction remains concerning. This review will center on domestic and international salt reduction policies, as well as diverse strategies, given the detrimental effects of excessive dietary salt intake and the existing global salt intake scenario. Besides, we used visualization software to analyze the literature related to salt reduction research in the last five years to explore the research hotspots in this field. Our objective is to enhance public awareness regarding the imperative of reducing salt intake and promoting the active implementation of diverse salt reduction policies.

High-pressure processing enhances saltiness perception and sensory acceptability of raw but not of cooked cured pork loins-leveraging salty and umami taste

The salt (NaCl) content in processed meats must be reduced because of its adverse effects on cardiovascular health. However, reducing salt in meat products typically leads to a lower taste intensity and, thus, consumer acceptability. Industry interventions must reduce salt content while maintaining taste, quality, and consumer acceptability. In this context, high-pressure processing (HPP) has been proposed to enhance saltiness perception, though there are contradictory reports to date. The present work aimed to conduct a targeted experiment to ascertain the influence of HPP (300/600 MPa) and cooking (71°C) on saltiness perception and sensory acceptability of meat products. HPP treatment (300/600 MPa) did enhance those two sensory attributes (approx. +1 on a 9-point hedonic scale) in raw (uncooked) cured pork loins but did not in their cooked counterparts. Further, the partition coefficient of sodium (PNa+), as an estimate of Na+ binding strength to the meat matrix, and the content of umami-taste nucleotides were investigated as potential causes. No effect of cooking (71°C) and HPP (300/600 MPa) could be observed on the PNa+ at equilibrium. However, HPP treatment at 300 MPa increased the inosine-5'-monophosphate (IMP) content in raw cured pork loins. Finally, hypothetical HPP effects on taste-mediating molecular mechanisms are outlined and discussed in light of boosting the sensory perception of raw meat products as a strategy to achieve effective salt reductions while keeping consumer acceptability.

Challenges and processing strategies to produce high quality frozen meat

Freezing is an effective means to extend the shelf-life of meat products. However, freezing and thawing processes lead to physical (e.g., ice crystals formation and freezer burn) and biochemical changes (e.g., protein denaturation and lipid oxidation) in meat resulting in loss of quality. Over the last two decades, several attempts have been made to produce thawed meat with qualities similar to that of fresh meat to no avail. This is due to the fact that no single technique exists to date that can mitigate all the quality challenges caused by freezing and thawing. This is further confounded by the consumer perception of frozen meat as lower quality compared to equivalent fresh-never-frozen meat cuts. Therefore, it remains challenging for the meat industry to produce high quality frozen meat and increase consumer acceptability of frozen products. This review aimed to provide an overview of the applications of novel freezing and thawing technologies that could improve the quality of thawed meat including deep freezing, high pressure, radiofrequency, electro-magnetic resonance, electrostatic field, immersion solution, microwave, ohmic heating, and ultrasound. This review will also discuss the development in processing strategies such as optimising the ageing of meat pre- or post-freezing, and the integration of freezing and thawing in one process/regime to collapse the difference in quality between thawed meat and fresh-never-frozen equivalents.

A comprehensive review of the applications of bacteriophage-derived endolysins for foodborne bacterial pathogens and food safety: recent advances, challenges, and future perspective

Foodborne diseases are caused by food contaminated by pathogenic bacteria such as Escherichia coli, Salmonella, Staphylococcus aureus, Listeria monocytogenes, Campylobacter, and Clostridium, a critical threat to human health. As a novel antibacterial agent against foodborne pathogens, endolysins are peptidoglycan hydrolases encoded by bacteriophages that lyse bacterial cells by targeting their cell wall, notably in Gram-positive bacteria due to their naturally exposed peptidoglycan layer. These lytic enzymes have gained scientists' interest in recent years due to their selectivity, mode of action, engineering potential, and lack of resistance mechanisms. The use of endolysins for food safety has undergone significant improvements, which are summarized and discussed in this review. Endolysins can remove bacterial biofilms of foodborne pathogens and their cell wall-binding domain can be employed as a tool for quick detection of foodborne pathogens. We explained the applications of endolysin for eliminating pathogenic bacteria in livestock and various food matrices, as well as the limitations and challenges in use as a dietary supplement. We also highlight the novel techniques of the development of engineering endolysin for targeting Gram-negative bacterial pathogens. In conclusion, endolysin is safe and effective against foodborne pathogens and has no adverse effect on human cells and beneficial microbiota. As a result, endolysin could be employed as a functional bio-preservative agent to improve food stability and safety and maintain the natural taste of food quality.

Effect of high pressure processing and water activity on pressure resistant spoilage lactic acid bacteria (Latilactobacillus sakei) in a ready-to-eat meat emulsion model

The main use of High Pressure Processing (HPP) in food processing is microorganism inactivation, and studies demonstrated that the characteristics of matrix and microorganisms can interfere on it. As the behavior of lactic acid bacteria exposed to different water activity (a_w) levels in a meat product is still unclear, this study aimed to determine the effect of pressure, time, and a_w to inactivate Latilactobacillus sakei, a pressure resistant lactic acid bacteria (LAB) in a meat emulsion model through a response surface methodology. The meat emulsion model was designed with adjusted a_w (from 0.940 to 0.960) and was inoculated with a pressure resistant LAB and processed varying pressure (400-600 MPa) and time (180-480 s), following the Central Composite Rotational Design (CCRD). The inactivation of the microorganism ranged from 0.99 to 4.12 UFC/g depending on the applied condition. At studied conditions, according to the best fitting and most significant polynomial equation (R² of 89.73 %), in a meat emulsion model, a_w had no influenced on HPP inactivation on LAB (p > 0.05) and only pressure and holding time had significative impact on it. The results of experimental validation of the mathematical model were satisfactory, confirming the suitability of the model. The information obtained in the present study stands out the matrix, microorganism and process effects at HPP efficiency. The answers obtained support food processors in product development, process optimization and food waste reduction.

The Effect of High-Pressure Processing on the Survival of Non-O157 Shiga Toxin-Producing Escherichia coli in Steak Tartare: The Good- or Best-Case Scenario?

Samples of steak tartare were artificially contaminated with a cocktail of Shiga toxin-producing Escherichia coli (STEC) O91, O146, O153, and O156 to the level of 3 log and 6 log CFU/g. Immediately after vacuum packing, high-pressure processing (HPP) was performed at 400 or 600 MPa/5 min. Some of the samples not treated with HPP were cooked under conditions of 55 °C for 1, 3, or 6 h. HPP of 400 MPa/5 min resulted in a 1-2 log reduction in the STEC count. In contrast, HPP of 600 MPa/5 min led to the elimination of STEC even when inoculated to 6 log CFU/g. Nevertheless, sub-lethally damaged cells were resuscitated after enrichment, and STEC was observed in all samples regardless of the pressure used. STEC was not detected in the samples cooked in a 55 °C water bath for 6 h, even after enrichment. Unfortunately, the temperature of 55 °C negatively affected the texture of the steak tartare. Further experiments are necessary to find an optimal treatment for steak tartare to assure its food safety while preserving the character and quality of this attractive product.

The effect of sodium tartrate and sodium citrate on quality changes of squid (Dosidicus gigas) surimi gel

The yield of squid has grown gradually; however, the lack of intensive processing has led to the slow development of the squid industry. In a previous study, some organic salts were found to improve the quality of squid surimi gel. Therefore, this research focused on the effects of sodium citrate (SC) and sodium tartrate (ST) on the quality of squid surimi gel. Physical measurements, such as gel texture, water-holding capacity, and color of squid surimi gel, were conducted. The addition of 2.5% SC and ST significantly improved the gel strength by 40.7, 57.0, 22.9, and 58.1%, respectively, of gel strength compared with the addition of: 1.5 SC, 3.5 SC, 1.5 ST, and 3.5% ST alone. Rheological measurements revealed that the addition of 2.5% SC or ST shortened the gel degradation temperature range (i.e., 2.5% SC or ST: 40-53°C; other treatments: 40-60°C) of the squid paste during heating. Results of chemical force analysis showed that the addition of a high quantity of salt accelerated protein aggregation and reduced hydrophobic interactions and disulfide bond formation. Finally, an increase in the number of β-sheets and a decrease in the bulk water content demonstrated that the addition of 2.5% organic salt could form squid gel with a better network structure. The findings provide a scientific basis for the development of high-quality squid surimi gel.

Principles, Application, and Gaps of High-Intensity Ultrasound and High-Pressure Processing to Improve Meat Texture

In this study, we evaluate the most recently applied emerging non-thermal technologies (NTT) to improve meat tenderization, high-intensity ultrasound (HIUS), and high-pressure processing (HPP), aiming to understand if individual effects are beneficial and how extrinsic and intrinsic factors influence meat toughness. We performed a systematic literature search and meta-analysis in four databases (Web of Science, Scopus, Embase, and PubMed). Among the recovered articles (n = 192), 59 studies were included. We found better sonication time in the range of 2-20 min. Muscle composition significantly influences HIUS effects, being type IIb fiber muscles more difficult to tenderize (p < 0.05). HPP effects are beneficial to tenderization at 200-250 MPa and 15-20 min, being lower and higher conditions considered inconclusive, tending to tenderization. Despite these results, undesirable physicochemical, microstructural, and sensory alterations are still unknown or represent barriers against applying NTT at the industrial level. Optimization studies and more robust analyses are suggested to enable its future implementation. Moreover, combining NTT with plant enzymes demonstrates an interesting alternative to improve the tenderization effect caused by NTT. Therefore, HIUS and HPP are promising technologies for tenderization and should be optimized considering time, intensity, pressure, muscle composition, undesirable changes, and combination with other methods.

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.

High pressure processing at the early stages of ripening enhances the safety and quality of dry fermented sausages elaborated with or without starter culture

To study the quality of chorizo de León dry fermented sausages (DFS), high pressure processing (HPP) applied at the early stages of ripening and the use of a functional starter culture were evaluated as additional safety measures. Furthermore, the ability to control the populations of artificially inoculated Listeria monocytogenes and Salmonella Typhimurium was investigated and the evolution of microbial communities was assessed by amplicon 16S rRNA metataxonomics. The use of HPP and the starter culture, independently or combined, induced a reduction of Listeria monocytogenes of 1.5, 4.3 and > 4.8 log CFU/g respectively, as compared to control. Salmonella Typhimurium counts were under the detection limit (<1 log) in all treated end-product samples. Both additional measures reduced the activity of undesirable microbiota, such as Serratia and Brochothrix, during the production of DFS. Moreover, the starter culture highly influencedthe taxonomic profile of samples.No adverse sensory effects were observed, and panelists showed preference for HPP treated DFS. In conclusion, this new approach of applying HPP at the early stages of ripening of DFS in combination with the use of a defined starter culture improved the safety and quality of the meat product.

Modifying textural and functional characteristics of fish (Nemipterus japonicus) mince using high pressure technology

Effect of high pressure in inducing textural and functional modification has been investigated in pink perch (Nemipterus japonicus) mince. Fish mince undergone pressurization at 200, 400 and 600 MPa for a holding period of 10 min and was compared against cooked mince (90 °C; 40 min). The treated mince at 400 and 600 MPa lost its natural viscosity and behaved like cooked mince through denaturation and formation of protein aggregates. Textural characterisation showed the retention of tenderness in 200 MPa treated samples, but become harder on application of higher pressures. Unlike heat gels, pressure induced gels were more smooth, white and elastic in nature. A decreased in reactive SH groups was observed in 400 and 600 MPa treated samples due to the formation of disulfide bonds. Hydrophobic concentration was higher in cooked and 600 MPa treatments whereas Ca2+-ATPase activity decreased after pressurization. On application of different pressures microbial reduction of 2-3 log cycles was achieved in the mince samples. Hence pressure treatments at lower ranges cannot alter the texture and functionality of protein and the mince can undergo processing as required. Besides extending shelf life, the treatments above 400 MPa can make irreversible effect on texture quality and protein functionality which is similar to that of cooking.

Processing interventions for enhanced microbiological safety of beef carcasses and beef products: A review

Chilled beef is inevitably contaminated with microorganisms, starting from the very beginning of the slaughter line. A lot of studies have aimed to improve meat safety and extend the shelf life of chilled beef, of which some have focused on improving the decontamination effects using traditional decontamination interventions, and others have investigated newer technologies and methods, that offer greater energy efficiency, lower environmental impacts, and better assurances for the decontamination of beef carcasses and cuts. To inform industry, there is an urgent need to review these interventions, analyze the merits and demerits of each technology, and provide insight into 'best practice' to preserve microbial safety and beef quality. In this review, the strategies and procedures used to inhibit the growth of microorganisms on beef, from slaughter to storage, have been critiqued. Critical aspects, where there is a lack of data, have been highlighted to help guide future research. It is also acknowledge that different intervention programs for microbiological safety have different applications, dependent on the initial microbial load, the type of infrastructures, and different stages of beef processing.

Application and challenge of bacteriophage in the food protection

In recent years, foodborne diseases caused by pathogens have been increasing. Therefore, it is essential to control the growth and transmission of pathogens. Bacteriophages (phages) have the potential to play an important role in the biological prevention, control, and treatment of these foodborne diseases due to their favorable advantages. Phages not only effectively inhibit pathogenic bacteria and prolong the shelf life of food, but also possess the advantages of specificity and an absence of chemical residues. Currently, there are many cases of phage applications in agriculture, animal disease prevention and control, food safety, and the treatment of drug-resistant disease. In this review, we summarize the recent research progress on phages against foodborne pathogenic bacteria, including Escherichia coli, Salmonella, Campylobacter, Listeria monocytogenes, Shigella, Vibrio parahaemolyticus, and Staphylococcus aureus. We also discuss the main issues and their corresponding solutions in the application of phages in the food industry. In recent years, although researchers have discovered more phages with potential applications in the food industry, most researchers use these phages based on their host spectrum, and the application environment is mostly in the laboratory. Therefore, the practical application of these phages in different aspects of the food industry may be unsatisfactory and even have some negative effects. Thus, we suggest that before using these phages, it is necessary to identify their specific receptors. Using their specific receptors as the selection basis for their application and combining phages with other phages or phages with traditional antibacterial agents may further improve their safety and application efficiency. Collectively, this review provides a theoretical reference for the basic research and application of phages in the food industry.

Microbiological Safety and Shelf-Life of Low-Salt Meat Products-A Review

Salt is widely employed in different foods, especially in meat products, due to its very diverse and extended functionality. However, the high intake of sodium chloride in human diet has been under consideration for the last years, because it is related to serious health problems. The meat-processing industry and research institutions are evaluating different strategies to overcome the elevated salt concentrations in products without a quality reduction. Several properties could be directly or indirectly affected by a sodium chloride decrease. Among them, microbial stability could be shifted towards pathogen growth, posing a serious public health threat. Nonetheless, the majority of the literature available focuses attention on the sensorial and technological challenges that salt reduction implies. Thereafter, the need to discuss the consequences for shelf-life and microbial safety should be considered. Hence, this review aims to merge all the available knowledge regarding salt reduction in meat products, providing an assessment on how to obtain low salt products that are sensorily accepted by the consumer, technologically feasible from the perspective of the industry, and, in particular, safe with respect to microbial stability.

The Effects of High-Pressure Processing on pH, Thiobarbituric Acid Value, Color and Texture Properties of Frozen and Unfrozen Beef Mince

In this study, beef mince (approximately 4% fat longissmus costarum muscle of approximately 2-year-old Holstein cattle) was used as a material. High-pressure processing (HPP) was applied to frozen and unfrozen, vacuum-packed minced meat samples. The pH and thiobarbituric acid (TBA) values of the samples were examined during 45 days of storage. Color values (L*, a* and b*) and texture properties were examined during 30 days of storage. After freezing and HPP (350 MPa, 10 min, 10 °C), the pH value of minced meat increased (p > 0.05) and its TBA value decreased (p < 0.05). The increase in pH may be due to increased ionization during HPP. Some meat peptides, which are considered antioxidant compounds, increased the oxidative stability of meat, so a decrease in TBA may have been observed after freezing and HPP. While the color change in unpressurized samples was a maximum of 3.28 units during storage, in the pressurized sample, it exceeded the limit of 10 units on the first day of storage and exceeded the limit of 10 units on the third day of storage in the frozen and pressurized sample. Freezing and HPP caused the color of beef mince to be retained longer. The hardness, gumminess, chewability, adherence, elasticity, flexibility values of the pressurized and pressurized after freezing samples were higher than those of the unpressurized samples during storage. On the other hand, the opposite was the case for the adhesiveness values. In industrial applications, meat must be pressurized after being vacuum packed. If HPP is applied to frozen beef mince, some of its properties such as TBA, color, and texture can be preserved for a longer period of time without extreme change.

EFSA Panel on Biological Hazards (BIOHAZ Panel), Koutsoumanis K, Alvarez‐Ordóñez A, Bolton D, Bover‐Cid S, Chemaly M, Davies R, De Cesare A, Herman L, Hilbert F, Lindqvist R, Nauta M, Peixe L, Ru G, Simmons M, Skandamis P, Suffredini E, Castle L, Crotta M, Grob K, Milana MR, Petersen A, Roig Sagués AX, Vinagre Silva F, Barthélémy E, Christodoulidou A, Messens W, Allende A. The efficacy and safety of high-pressure processing of food

High-pressure processing (HPP) is a non-thermal treatment in which, for microbial inactivation, foods are subjected to isostatic pressures (P) of 400-600 MPa with common holding times (t) from 1.5 to 6 min. The main factors that influence the efficacy (log10 reduction of vegetative microorganisms) of HPP when applied to foodstuffs are intrinsic (e.g. water activity and pH), extrinsic (P and t) and microorganism-related (type, taxonomic unit, strain and physiological state). It was concluded that HPP of food will not present any additional microbial or chemical food safety concerns when compared to other routinely applied treatments (e.g. pasteurisation). Pathogen reductions in milk/colostrum caused by the current HPP conditions applied by the industry are lower than those achieved by the legal requirements for thermal pasteurisation. However, HPP minimum requirements (P/t combinations) could be identified to achieve specific log10 reductions of relevant hazards based on performance criteria (PC) proposed by international standard agencies (5-8 log10 reductions). The most stringent HPP conditions used industrially (600 MPa, 6 min) would achieve the above-mentioned PC, except for Staphylococcus aureus. Alkaline phosphatase (ALP), the endogenous milk enzyme that is widely used to verify adequate thermal pasteurisation of cows' milk, is relatively pressure resistant and its use would be limited to that of an overprocessing indicator. Current data are not robust enough to support the proposal of an appropriate indicator to verify the efficacy of HPP under the current HPP conditions applied by the industry. Minimum HPP requirements to reduce Listeria monocytogenes levels by specific log10 reductions could be identified when HPP is applied to ready-to-eat (RTE) cooked meat products, but not for other types of RTE foods. These identified minimum requirements would result in the inactivation of other relevant pathogens (Salmonella and Escherichia coli) in these RTE foods to a similar or higher extent.

Effect of Partial Substitution of Sodium Chloride (NaCl) with Potassium Chloride (KCl) Coupled with High-Pressure Processing (HPP) on Physicochemical Properties and Volatile Compounds of Beef Sausage under Cold Storage at 4 °C

This study aimed to evaluate the effects of partial substitution of sodium chloride (NaCl) with potassium chloride (KCl) in combination with high-pressure processing (HPP) on the physicochemical properties and volatile compounds of beef sausage during cold storage at 4 °C. Significant differences were found in the volatile compounds of beef sausages with 0%, 25%, and 50% NaCl contents partially substituted with KCl subjected to 28 days of storage and were well-visualized by heat map analysis. A total of 75 volatile compounds were identified and quantified in the beef sausages at the end of 28 days of storage, including 12 aldehydes, 4 phenols, 2 ketones, 18 alcohols, 8 acids, 3 esters, 14 terpenes, and 14 alkanes. Thirteen compounds had low odor activity values (OAV) (OAV < 1); however, high OAV (OAV > 1) were obtained after partial substitution of NaCl by KCl at 25% and 50% with HPP treatment compared to the non-HPP treated samples. In addition, 50% NaCl substitution with KCl in conjunction with HPP treatments increased thiobarbituric acid reactive substances (TBARS) by (0.46 ± 0.03 mg/MDA) compared with no HPP treatments. Replacement of 25% and 50% NaCl with KCl decreased TBARS by an average of 10.8% and 11.10%, respectively, compared to 100% NaCl coupled with HPP beef sausages. In summary, HPP and partial substitution of NaCl with KCl at 25% and 50% can be used to compensate for the reduction of NaCl in beef sausage by keeping the physical and flavor fraction at required levels.

Strategies for Nitrite Replacement in Fermented Sausages and Effect of High Pressure Processing against Salmonella spp. and Listeria innocua

The development of nitrite-free meat products is a current industrial concern. Many efforts have been attempted to replace the nitrite effect in cured meats colour formation and pathogens control. Our previous work evidenced that lactic acid and a cold ripening were the best hurdle technologies for nitrite-free fermented sausages from metabolomics. In the first part of this work, we investigated the effect of lactic acid compared with both two alternative additives (glucono-D-lactone and a mix of sodium di-acetate/sodium lactate) and with low-nitrite sausages, all of them following either cold or traditional ripening. For this purpose, microbiological analysis, pH, water activity (aw), and a sensory study were performed. All nitrite-free sausages (cold or traditional ripened) showed quality and safety traits similar to low-nitrite traditionally ripened ones used as control. In addition, sensory study revealed that sausages with lactic acid were the most preferred cold ripened samples, supporting that this is an optimal strategy for the production of nitrite-free sausages. We selected this product for further studies. Indeed, in the second part, we evaluated the impact of ripening, and other hurdle technologies as High Pressure Processing (HPP) and under-vacuum storage against Listeria innocua and Salmonella spp. by a challenge test. Maximal declines were obtained for ripening along with HPP (i.e., 4.74 and 3.83 log CFU/g for L. innocua and Salmonella spp., respectively), suggesting that HPP might guarantee nitrite-free sausages safety. Although the quality of raw materials remains essential, these hurdle strategies largely contributed to nitrite-free sausages safety, offering a promising tool for the meat industry.

Volatile compounds in high-pressure-treated dry-cured ham: A review

The use of high pressure processing (HPP) for the treatment of dry-cured ham and other meat products has considerably increased worldwide. Its well-documented lethal effect on pathogenic and spoilage bacteria ensures the microbial safety of dry-cured ham and extends its shelf life. However, the effects of HPP on the volatile compounds, odor and aroma of dry-cured ham are less known. In the present review, the effects of HPP on the enzymes and microorganisms responsible for the generation of volatile compounds in dry-cured ham and the changes in the levels of the main groups of volatile compounds resulting from different HPP treatments are discussed. Particular attention is devoted to the fate of odor-active compounds after HPP treatments and throughout further commercial storage. The use of efficient sensory techniques yielding odor and aroma outputs closer to those perceived by consumers is encouraged. Needs for future research on the volatile compounds, odor and aroma of HPP-treated dry-cured ham are highlighted.

Phage and phage lysins: New era of bio-preservatives and food safety agents

There has been an increase in the search and application of new antimicrobial agents as alternatives to use of chemical preservatives and antibiotic-like compounds by the food industry. The massive use of antibiotic has created a reservoir of antibiotic-resistant bacteria that find their way from farm to humans. Thus, there exists an imperative need to explore new antibacterial options and bacteriophages perfectly fit into the class of safe and potent antimicrobials. Phage bio-control has come a long way owing to advances with use of phage cocktails, recombinant phages, and phage lysins; however, there still exists unmet challenges that restrict the number of phage-based products reaching the market. Hence, further studies are required to explore for more efficient phage-based bio-control strategies that can become an integral part of food safety protocols. This review thus aims to highlight the recent developments made in the application of phages and phage enzymes covering pre-harvest as well as post-harvest usage. It further focuses on the major issues in both phage and phage lysin research hindering their optimum use while detailing out the advances made by researchers lately in this direction for full exploitation of phages and phage lysins in the food sector.

High hydrostatic pressure combined with moisture regulators improves the tenderness and quality of beef jerky

The influence of high hydrostatic pressure (HHP) at different pressure levels (0.1, 100, 200, and 300 MPa) combined with moisture regulators (MR) on the tenderness, water content, and quality of beef jerky was investigated. HHP treatment reduced the shear force (SF) of beef jerky (P < 0.05). The beef jerky treated with MR+HHP exhibited higher tenderness than the beef jerky treated only with HHP (P < 0.05). The MR+HHP samples had significantly higher moisture content than the HHP samples (P > 0.05) when the water activity was maintained at approximately 0.7. MR+HHP contributed to a shorter T₂₁ value and a higher P₂₁ value, which indicated an improvement in the water-binding ability of the beef muscle. Analysis of the microstructure showed that MR+HHP led to the fracture of the Z-line and destruction of the sarcomere structure. Sensory analysis showed that MR+HHP-200 samples had significantly higher tenderness and overall acceptable scores than other samples (P < 0.05).

Combination of Natural Compounds With Novel Non-thermal Technologies for Poultry Products: A Review

Ensuring safe, fresh, and healthy food across the shelf life of a commodity is an ongoing challenge, with the driver to minimize chemical additives and their residues in the food processing chain. High-value fresh protein products such as poultry meat are very susceptible to spoilage due to oxidation and bacterial contamination. The combination of non-thermal processing interventions with nature-based alternatives is emerging as a useful tool for potential adoption for safe poultry meat products. Natural compounds are produced by living organisms that are extracted from nature and can be used as antioxidant, antimicrobial, and bioactive agents and are often employed for other existing purposes in food systems. Non-thermal technology interventions such as high-pressure processing, pulsed electric field, ultrasound, irradiation, and cold plasma technology are gaining increasing importance due to the advantages of retaining low temperatures, nutrition profiles, and short treatment times. The non-thermal unit process can act as an initial obstacle promoting the reduction of microflora, while natural compounds can provide an active obstacle either in addition to processing or during storage time to maintain quality and inhibit and control growth of residual contaminants. This review presents the application of natural compounds along with emerging non-thermal technologies to address risks in fresh poultry meat.

Modeling the effect of simultaneous use of allyl isothiocyanate and cinnamaldehyde on high hydrostatic pressure inactivation of Uropathogenic and Shiga toxin-producing Escherichia coli in ground chicken

BACKGROUND

A combination of high-pressure processing (HPP) and antimicrobials is a well-known approach for enhancing the microbiological safety of foods. However, few studies have applied multiple antimicrobials simultaneously with HPP, which could be an additional hurdle for microbial inactivation. The present study applied a full factorial design to investigate the impact of HPP (225-325 MPa; 10-20 min), allyl isothiocyanate (AITC) (0.3-0.9 g kg^-1 ) and trans-cinnamaldehyde (tCinn) (1.0-2.0 g kg^-1 ) on the inactivation of Shiga toxin-producing Escherichia coli (STEC) O157:H7 and uropathogenic E. coli (UPEC) in ground chicken meat.

RESULTS

The regulatory requirement of 5-log reduction was achieved at 305 MPa, 18 min, 0.8 g kg^-1 AITC and 1.7 g kg^-1 tCinn for STEC O157:H7 and at 293 MPa, 16 min, 0.6 g kg^-1 AITC and 1.6 g kg^-1 tCinn for UPEC, as specified by response surface analysis and verified via experiments. The surviving population was eliminated by post-treatment storage of 9 days at 10 °C. The developed linear regression models showed r²  > 0.9 for the E. coli inactivation. The developed dimensionless non-linear regression models covered a factorial range slightly wider than the original experimental limit, with probability P_r  > F (< 0.0001).

CONCLUSION

Simultaneous use of AITC and tCinn reduced not only the necessary concentration of each compound, but also the intensity of high-pressure treatments, at the same time achieving a similar level of microbial inactivation. STEC O157:H7 was found to be more resistant than UPEC to the HPP-AITC-tCinn stress. The developed models may be applied in commercial application to enhance the microbiological safety of ground chicken meat. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.

Inactivation of Foodborne Viruses by High-Pressure Processing (HPP)

High-pressure processing (HPP) is an innovative non-thermal food preservation method. HPP can inactivate microorganisms, including viruses, with minimal influence on the physicochemical and sensory properties of foods. The most significant foodborne viruses are human norovirus (HuNoV), hepatitis A virus (HAV), human rotavirus (HRV), hepatitis E virus (HEV), human astrovirus (HAstV), human adenovirus (HuAdV), Aichi virus (AiV), sapovirus (SaV), and enterovirus (EV), which have also been implicated in foodborne outbreaks in various countries. The HPP inactivation of foodborne viruses in foods depends on high-pressure processing parameters (pressure, temperature, and duration time) or non-processing parameters such as virus type, food matrix, water activity (aw), and the pH of foods. HPP was found to be effective for the inactivation of foodborne viruses such as HuNoV, HAV, HAstV, and HuAdV in foods. HPP treatments have been found to be effective at eliminating foodborne viruses in high-risk foods such as shellfish and vegetables. The present work reviews the published data on the effect of HPP processing on foodborne viruses in laboratory media and foods.

Innovative Characterization Based on Stress Relaxation and Creep to Reveal the Tenderizing Effect of Ultrasound on Wooden Breast

In order to explore a new strategy to characterize the texture of raw meat, based on the ultrasonic tenderized wooden breast (WB), this study proposed stress relaxation and creep to determine the rheological properties. Results showed that hardness was significantly decreased from 3625.61 g to 2643.64 g, and elasticity increased, after 600 W ultrasound treatment at 20 kHz for 20 min (on-time 2 s and off-time 3 s) at 4 °C. In addition, based on the transformation of creep data, a new indicator, slope ε'(t), was innovatively used to simulate a sensory feedback of hardness from the touch sensation, proving WB became tender at 600 W treatment due to the feedback speed to external force. These above results were confirmed by the reduced shear force, increased myofibril fragmentation index (MFI), decreased particle size, and increased myofibrillar protein degradation. Histology analysis and collagen suggested the tenderizing results was caused by muscle fiber rather than connective tissue. Overall, stress relaxation and creep had a potential to predict meat texture characteristics and 600 W ultrasound treatment was an effective strategy to reduce economic losses of WB.

Non-Thermal Methods for Ensuring the Microbiological Quality and Safety of Seafood

A literature search and systematic review were conducted to present and discuss the most recent research studies for the past twenty years on the application of non-thermal methods for ensuring the microbiological safety and quality of fish and seafood. This review presents the principles and reveals the potential benefits of high hydrostatic pressure processing (HHP), ultrasounds (US), non-thermal atmospheric plasma (NTAP), pulsed electric fields (PEF), and electrolyzed water (EW) as alternative methods to conventional heat treatments. Some of these methods have already been adopted by the seafood industry, while others show promising results in inactivating microbial contaminants or spoilage bacteria from solid or liquid seafood products without affecting the biochemical or sensory quality. The main applications and mechanisms of action for each emerging technology are being discussed. Each of these technologies has a specific mode of microbial inactivation and a specific range of use. Thus, their knowledge is important to design a practical application plan focusing on producing safer, qualitative seafood products with added value following today’s consumers’ needs.