Effect of rosemary extract on microbial growth, pH, color, and lipid oxidation in cold plasma-processed ground chicken patties

The Effect of Plasma-Activated Water Combined with Rosemary Extract (Rosmarinus officinalis L.) on the Physicochemical Properties of Frankfurter Sausage during Storage

This study investigated the impact of plasma-activated water (PAW) and rosemary extract on the bacterial inactivation and quality attributes of Frankfurter sausages during a 6-day storage period. The antibacterial activity, total phenol content (TPC), and total flavonoid content (TFC) of the rosemary extract were evaluated. The TPC of the rosemary extract was 89.45 mg gallic acid/g dry weight, while the TFC was 102.3 mg QE/g dry weight. Even at low concentrations, the rosemary extract effectively inhibited the growth of all the tested pathogens using the Well Diffusion Agar method (WDA). The sausages were treated with different concentrations of PAW and rosemary extract and stored for 1 and 6 days. Sample B (100% rosemary extract + PAW treatment) showed the greatest reduction in microbial load and was selected for further analysis. Throughout the storage period, Sample B exhibited no significant changes in pH, moisture content, textural parameters, or sensory evaluation compared to the control group. However, the hardness and color parameters (L*, a*) of Sample B decreased, while the TBARS value increased after 6 days of storage. The combination of PAW and rosemary extract, particularly Sample B, effectively inhibited bacterial growth in the Frankfurter sausages without compromising most quality attributes. Some changes in hardness, color, and lipid oxidation were observed over the extended storage period.

Innovative Application of Cold Plasma Technology in Meat and Its Products

The growing demand for sustainable food production and the rising consumer preference for fresh, healthy, and safe food products have been driving the need for innovative methods for processing and preserving food. In the meat industry, this demand has led to the development of new interventions aimed at extending the shelf life of meats and its products while maintaining their quality and nutritional value. Cold plasma has recently emerged as a subject of great interest in the meat industry due to its potential to enhance the microbiological safety of meat and its products. This review discusses the latest research on the possible application of cold plasma in the meat processing industry, considering its effects on various quality attributes and its potential for meat preservation and enhancement. In this regard, many studies have reported substantial antimicrobial efficacy of cold plasma technology in beef, pork, lamb and chicken, and their products with negligible changes in their physicochemical attributes. Further, the application of cold plasma in meat processing has shown promising results as a potential novel curing agent for cured meat products. Understanding the mechanisms of action and the interactions between cold plasma and food ingredients is crucial for further exploring the potential of this technology in the meat industry, ultimately leading to the development of safe and high-quality meat products using cold plasma technology.

Cold Plasma-Assisted Extraction of Phytochemicals: A Review

In recent years, there has been growing interest in bioactive plant compounds for their beneficial effects on health and for their potential in reducing the risk of developing certain diseases such as cancer, cardiovascular diseases, and neurodegenerative disorders. The extraction techniques conventionally used to obtain these phytocompounds, however, due to the use of toxic solvents and high temperatures, tend to be supplanted by innovative and unconventional techniques, in line with the demand for environmental and economic sustainability of new chemical processes. Among non-thermal technologies, cold plasma (CP), which has been successfully used for some years in the food industry as a treatment to improve food shelf life, seems to be one of the most promising solutions in green extraction processes. CP is characterized by its low environmental impact, low cost, and better extraction yield of phytochemicals, saving time, energy, and solvents compared with other classical extraction processes. In light of these considerations, this review aims to provide an overview of the potential and critical issues related to the use of CP in the extraction of phytochemicals, particularly polyphenols and essential oils. To review the current knowledge status and future insights of CP in this sector, a bibliometric study, providing quantitative information on the research activity based on the available published scientific literature, was carried out by the VOSviewer software (v. 1.6.18). Scientometric analysis has seen an increase in scientific studies over the past two years, underlining the growing interest of the scientific community in this natural substance extraction technique. The literature studies analyzed have shown that, in general, the use of CP was able to increase the yield of essential oil and polyphenols. Furthermore, the composition of the phytoextract obtained with CP would appear to be influenced by process parameters such as intensity (power and voltage), treatment time, and the working gas used. In general, the studies analyzed showed that the best yields in terms of total polyphenols and the antioxidant and antimicrobial properties of the phytoextracts were obtained using mild process conditions and nitrogen as the working gas. The use of CP as a non-conventional extraction technique is very recent, and further studies are needed to better understand the optimal process conditions to be adopted, and above all, in-depth studies are needed to better understand the mechanisms of plasma-plant matrix interaction to verify the possibility of any side reactions that could generate, in a highly oxidative environment, potentially hazardous substances, which would limit the exploitation of this technique at the industrial level.

A comprehensive review on infant formula: nutritional and functional constituents, recent trends in processing and its impact on infants' gut microbiota

Human milk is considered the most valuable form of nutrition for infants for their growth, development and function. So far, there are still some cases where feeding human milk is not feasible. As a result, the market for infant formula is widely increasing, and formula feeding become an alternative or substitute for breastfeeding. The nutritional value of the formula can be improved by adding functional bioactive compounds like probiotics, prebiotics, human milk oligosaccharides, vitamins, minerals, taurine, inositol, osteopontin, lactoferrin, gangliosides, carnitine etc. For processing of infant formula, diverse thermal and non-thermal technologies have been employed. Infant formula can be either in powdered form, which requires reconstitution with water or in ready-to-feed liquid form, among which powder form is readily available, shelf-stable and vastly marketed. Infants' gut microbiota is a complex ecosystem and the nutrient composition of infant formula is recognized to have a lasting effect on it. Likewise, the gut microbiota establishment closely parallels with host immune development and growth. Therefore, it must be contemplated as an important factor for consideration while developing formulas. In this review, we have focused on the formulation and manufacturing of safe and nutritious infant formula equivalent to human milk or aligning with the infant's needs and its ultimate impact on infants' gut microbiota.

Antimicrobial activity of cold atmospheric-pressure argon plasma combined with chicory (Cichorium intybus L.) extract against P. aeruginosa and E. coli biofilms

The present study reports a significant combined antibacterial activity of Cichorium intybus L. (known as Chicory) natural extract with cold atmospheric-pressure argon plasma treatment against multi-drug resistant (MDR) Gram-negative bacteria. To detect reactive species that are generated in the argon plasma, optical emission spectra were recorded. The molecular bands were allocated to the hydroxyl radicals (OH) and neutral nitrogen molecules (N2). Moreover, the atomic lines form the emitted spectra were determined to argon atoms (Ar) and the oxygen atoms (O), respectively. The results revealed that Chicory extract treatment at a concentration of 0.043 g/ml reduced the metabolic activity of P. aeruginosa cells by 42%, while, a reduced metabolic activity of 50.6% was found for E. coli biofilms. Moreover, the combination of Chicory extract with 3 min Ar-plasma introduced a synergistic effect, so that it exhibited a significantly reduced metabolic activity of P. aeruginosa to 84.1%, and E. coli ones to 86.7%, respectively. The relationship between cell viability and membrane integrity of P. aeruginosa and E. coli biofilms treated with Chicory extract and argon plasma jet were also analyzed by CLSM. It was found that after the combined treatment, a noticeable membrane disruption was formed. Besides, it was concluded that E. coli biofilms showed a higher sensitivity to Ar-plasma than P. aeruginosa biofilm at longer plasma exposure times. This study suggests that the anti-biofilm therapy based on a combined effect of Chicory extract and cold argon plasma treatment can serve as a considerable green method for treatment of antimicrobial MDR bacteria.

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 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.

Effect of commercial plant extracts on the oxidative stability of mechanically deboned poultry meat during chilled storage

The effect of commercial plant extracts (grape, rosemary, pomegranate, green tea, and mate) at 0.125, 0.25, 0.50, and 1 % w/w concentrations as a natural antioxidant in mechanically deboned poultry meat (MDPM) was evaluated. The extracts were characterized for the content of phenolic compounds, total flavonoids, and antioxidant activity. Lipid oxidation (TBARS), instrumental color (L*, a*, and b* values), and pH of MDPM were evaluated on days 0, 2, 4, 6, 8, and 10 of chilled storage (2 °C). All commercial extracts showed antioxidant activity in the following order: grape > green tea > mate > rosemary > pomegranate, the latter addition promoted the highest TBARS values in MDPM during storage. The levels of 0.5, 0.25, and 0.125 % of grape, green tea, mate, and rosemary extracts showed the same positive effect in decelerating lipid oxidation in MDPM. The pH values of the MDPM decreased with increasing the extract concentrations. The commercial extracts led to a decrease in L* and b* values, and the grape extract provided the highest a* values in MDPM during chilled storage. The addition of commercial plant-derived extracts has proven to be an effective natural antioxidant to extend the shelf life of MDPM and consequently healthier and quality meat products can be produced.

Emerging Trends for Nonthermal Decontamination of Raw and Processed Meat: Ozonation, High-Hydrostatic Pressure and Cold Plasma

Meat may contain natural, spoilage, and pathogenic microorganisms based on the origin and characteristics of its dietary matrix. Several decontamination substances are used during or after meat processing, which include chlorine, organic acids, inorganic phosphates, benzoates, propionates, bacteriocins, or oxidizers. Unfortunately, traditional decontamination methods are often problematic because of their adverse impact on the quality of the raw carcass or processed meat. The extended shelf-life of foods is a response to the pandemic trend, whereby consumers are more likely to choose durable products that can be stored for a longer period between visits to food stores. This includes changing purchasing habits from “just in time” products “for now” to “just in case” products, a trend that will not fade away with the end of the pandemic. To address these concerns, novel carcass-decontamination technologies, such as ozone, high-pressure processing and cold atmospheric plasma, together with active and clean label ingredients, have been investigated for their potential applications in the meat industry. Processing parameters, such as exposure time and processing intensity have been evaluated for each type of matrix to achieve the maximum reduction of spoilage microorganism counts without affecting the physicochemical, organoleptic, and functional characteristics of the meat products. Furthermore, combined impact (hurdle concept) was evaluated to enhance the understanding of decontamination efficiency without undesirable changes in the meat products. Most of these technologies are beneficial as they are cost-effective, chemical-free, eco-friendly, easy to use, and can treat foods in sealed packages, preventing the product from post-process contamination. Interestingly, their synergistic combination with other hurdle approaches can help to substitute the use of chemical food preservatives, which is an aspect that is currently quite desirable in the majority of consumers. Nonetheless, some of these techniques are difficult to store, requiring a large capital investment for their installation, while a lack of certification for industrial utilization is also problematic. In addition, most of them suffer from a lack of sufficient data regarding their mode of action for inactivating microorganisms and extending shelf-life stability, necessitating a need for further research in this area.

Natural alternatives for processed meat: Legislation, markets, consumers, opportunities and challenges

Consumers' interest in food with less and/or free from synthetic additives has increased considerably in recent years. In this context, researchers and industries have concentrated efforts on developing alternatives to these compounds. Replacing synthetic additives in meat products is a challenge, given their importance for sensory characteristics and food safety. Complementary technologies combined with the replacement and/or reduction of synthetic additives (hurdle technologies) has been studied focusing on the protection and extension of the shelf life of meat products. This review reports alternatives for replacing and/or reducing the use of synthetic additives in meat derivatives, aiming at the development of more natural and simpler meat products, familiar to consumers and considered clean labels.

Effect of the Application of Cold Plasma Energy on the Inactivation of Microorganisms, Proteins, and Lipids Deterioration in Adobera Cheese

Cheeses are perishable foods that must fulfill sanitary and quality requirements according to the parameters established globally. Plasma as a nonthermal inactivation technique has been a current research topic for food preservation, so the objective of this work was to study the effect of plasma energy against microorganisms in Adobera cheese (traditional Mexican cheese) as well as evaluate the possible degradation of lipids and protein. 108 CFU/mL of Escherichia coli ATCC 25922, Salmonella ATCC13076, and Staphylococcus aureus ATCC 6538 were inoculated at 0.5 g of Adobera cheese and were subjected to an energy of 30 volts, in a dielectric barrier discharge reactor (DBDR) at intervals of times 1, 3, 5, 7, 10, and 15 min. A flow of a mixture of air and helium at 96% purity was used. The decimal reduction time (D) was determined, and the oxidation of proteins and lipids was analyzed after each treatment. The results showed an annihilating effect of plasma on the indicator bacteria under study, and a reduction of 5 logarithmic cycles was obtained. The maximum degree of lipid oxidation was 23 acid degree values (ADV) after 7 min of exposure to plasma. The oxidation of proteins showed a direct and proportional relationship between the formation of carbonyl groups with the percentage significant loss to the concentration of carbonyl groups with the concentration of protein oxidation, after 3 min of exposure to cold plasma levels of 82% and 99% oxidation of Adobera cheese protein and free casein, respectively. We conclude that the plasma energy applied to Adobera cheese is an effective treatment to inactivate bacteria. However, there is the possibility of causing changes in taste and odor, due to the release of fatty acids and the oxidation of proteins.

Use of betel leaf (Piper betle L.) ethanolic extract in combination with modified atmospheric packaging and nonthermal plasma for shelf-life extension of Nile tilapia (Oreochromis niloticus) fillets

Fish is perishable and has the short shelf-life. To maintain its quality, it is necessary to implement the appropriate technology, particularly nonthermal processing along with safe additive, especially from plant origin under the concept of "hurdle technology". The use of potential vesicle including liposome for loading the plant extract could be a means to enhance the stability and activities of the extract. The current study aimed to evaluate the effect of liposomes loaded with betel leaf ethanolic extract (L/BLEEs) or unencapsulated BLEE (U/BLEE) in conjunction with modified atmospheric packaging (MAP) and nonthermal plasma (NTP) on the quality changes and shelf-life of Nile tilapia fillets (TFs) stored under refrigerated condition (4°C). TFs treated with L/BLEE or U/BLEE at 400 ppm, packed under modified atmosphere (CO₂ :Ar:O₂  = 60:30:10) and subjected to NTP for 300 s (L/BLEE-400/MAP-NTP and U/BLEE-400/MAP-NTP, respectively) had the lowest microbial and chemical changes during storage, while the control showed the highest changes (p < 0.05). Lipid oxidation was lower in these samples, ascertained by more retained polyunsaturated fatty acids and lower lipid oxidation based on Fourier transform infrared (FT-IR) spectra. Overall likeness scores were similar (p > 0.05) between all the samples at day 0 of storage. Only L/BLEE-400/MAP-NTP and U/BLEE-400/MAP-NTP were still sensorially acceptable after 12 days at 4°C. Therefore, L/BLEE or U/BLEE combined with MAP/NTP treatment could be adopted as a potent hurdle for shelf-life extension of TFs. PRACTICAL APPLICATION: Natural additives and nonthermal processing technologies have gained increasing interest for preservation of fish. Liposomes loaded with betel leaf ethanolic extract (L/BLEE) rich in polyphenolics could be used together with modified atmospheric packaging (MAP) and nonthermal plasma (NTP) to retard bacterial growth and chemical deterioration in Nile tilapia fillets. These hurdles were proven to be able to maintain the qualities of tilapia fillets stored at 4°C up to 12 days, especially when L/BLEE was used at 400 ppm. Therefore, shelf-life extension of Nile tilapia fillets or other fish can be achieved by using the natural additive and nonthermal processing technologies.

Strategies to increase the shelf life of meat and meat products with phenolic compounds

Oxidative reactions and microbial growth are the main processes involved in the loss of quality in meat products. Although the use of additives to improve the shelf life is a common practice in the meat industry, the current trends among consumers are pushing the researchers and professionals of the meat industry to reformulate meat products. Polyphenols are compounds with antioxidant and antimicrobial activity naturally found in several plants, fruits, and vegetables that can be used in the production of extracts and components in active packaging to improve the shelf life of meat products. This chapter aims to discuss the advances in terms of (1) encapsulation techniques to protect phenolic compounds; (2) production of active and edible packages rich on phenolic compounds; (3) use of phenolic-rich additives (free or encapsulated form) with non-thermal technologies to improve the shelf life of meat products; and (4) use of active packaging rich on phenolic compounds on meat products. Innovative strategies to encapsulated polyphenols and produce films are mainly centered in the use of innovative and emerging technologies (such as ultrasound and supercritical fluids). Moreover, the combined use of polyphenols and non-thermal technologies is a relevant approach to improve the shelf life of meat products, especially using high pressure processing. In terms of application of innovative films, nanomaterials have been largely explored and indicated as relevant strategy to preserve meat and meat products.

Physicochemical, Nutritional, Microbiological, and Sensory Qualities of Chicken Burgers Reformulated with Mediterranean Plant Ingredients and Health-Promoting Compounds

The quality of chicken burgers reformulated by the partial replacement of meat by Mediterranean plant ingredients and enriched with peculiar amounts of n-3 PUFAs, Mg, Fe, Se, and folic acid, was evaluated in comparison to conventional chicken burgers. Specifically, two types of burger were developed, namely the "Sicilian burger"-based on cherry tomato and rosemary-and the "Mediterranean burger"-with basil leaves and thyme essential oil-every recipe being differentially functionalized according to the nutritional requirements of consumers, such as children, pregnant women and elderly. Mediterranean ingredients were responsible for different pH, color, and cooking loss between conventional and functional burgers. Except for n-3 PUFAs resulting poorly fortified, the functionalization with Mg, Fe, Se, and vitamin B9 was successful in all products. Considering the target consumer categories, the daily consumption of the functional burger may assure an intake of Mg, Fe, and Se equal, respectively, to 37.31-59.90%, 17.76-46.81%, and 27.20-50.05%, and a cover of vitamin B9 of 31.98-48.31% of the relative population reference intakes. Fortified products kept a good microbiological quality during 5 days of refrigerated storage, and, according to the sensorial descriptive analysis and the hedonic test, they showed a higher acceptability than conventional burgers.

Non-thermal Technologies for Food Processing

Food is subjected to various thermal treatments during processes to enhance its shelf-life. But these thermal treatments may result in deterioration of the nutritional and sensory qualities of food. With the change in the lifestyle of people around the globe, their food needs have changed as well. Today's consumer demand is for clean and safe food without compromising the nutritional and sensory qualities of food. This directed the attention of food professionals toward the development of non-thermal technologies that are green, safe, and environment-friendly. In non-thermal processing, food is processed at near room temperature, so there is no damage to food because heat-sensitive nutritious materials are intact in the food, contrary to thermal processing of food. These non-thermal technologies can be utilized for treating all kinds of food like fruits, vegetables, pulses, spices, meat, fish, etc. Non-thermal technologies have emerged largely in the last few decades in food sector.

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.

Antimicrobial and Preservative Effects of the Combinations of Nisin, Tea Polyphenols, Rosemary Extract, and Chitosan on Pasteurized Chicken Sausage

ABSTRACT

This study was conducted to evaluate the antimicrobial and preservative effects of the combinations of nisin (NS), tea polyphenols (TP), rosemary extract (RE), and chitosan (CS) on pasteurized chicken sausage. An orthogonal test revealed that the most effective preservative was a mixture of 0.05% NS plus 0.05% TP plus 0.03% RE plus 0.55% CS (weight by sausage weight). This mixture had antimicrobial and antioxidant effects in pasteurized chicken sausage and extended the shelf life to >30 days at 4°C. The inhibitory effects of NS, TP, RE, and CS were also evaluated against Pseudomonas aeruginosa, lactic acid bacteria (LAB), and Staphylococcus aureus, the dominant spoilage and pathogenic bacteria in pasteurized chicken sausage. NS had the greatest inhibitory effect on LAB and S. aureus, with inhibitory zone diameters of 19.7 and 17.8 mm, respectively. TP had the largest inhibitory effect on P. aeruginosa, with a clear zone diameter of 18.2 mm. These results indicate that the combination of NS, TP, RE, and CS could be used as a natural preservative to efficiently inhibit the growth of microorganisms in pasteurized chicken sausage and improve its safety and shelf life.

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Antioxidant effect of acerola fruit powder, rosemary and licorice extract in caiman meat nuggets containing mechanically separated caiman meat

The aim of this work was to evaluate the antioxidant effect of acerola fruit powder, rosemary and licorice extract in caiman meat nuggets containing high amounts of mechanically separated caiman meat (MSCM) during 120 days of frozen storage. Five treatments were prepared: a control without antioxidant (CON), sodium erythorbate at 500 mg/kg (ERY), acerola fruit powder at 500 mg/kg (AFP), with licorice extract at 500 mg/kg (LIE) and rosemary extract at 500 mg/kg (ROE). The addition of natural antioxidants increased color, cohesiveness, and decreased TBARS values. The redness values were higher for LIE and these values were different to the CON. Nuggets with licorice extract had significantly lower TBARS values at the end of the storage period compared to the control. All the treatments were similar in sensory analysis, with good acceptability. These results indicate licorice extract used in caiman meat nuggets containing a high amount of MSCM caiman has the potential to improve quality during frozen storage.

Bacterial Community Assessed by Utilization of Single Carbon Sources in Broiler Ground Meat after Treatment with an Antioxidant, Carnosine, and Cold Plasma

ABSTRACT

Contaminated poultry meat is a major source of human foodborne illnesses. Many interventions have been developed to reduce and/or eliminate human foodborne pathogens in poultry products; however, treatments with cold plasma or carnosine or their combination have not been extensively investigated. In this study, the bacterial microflora of poultry meat samples after treatments with cold plasma and carnosine were characterized with EcoPlates in the OmniLog system. The plates were incubated at 25°C for 7 days in the OmniLog chamber, and bacterial growth was monitored by recording formazan production every 30 min at an optical density of 590 nm. The kinetics of lag, log, and stationary phases of bacterial growth followed the Gompertz sigmoidal model but with different inflection times and asymptotes at the log phase and the stationary phase, respectively. Results indicated that treatment of poultry meat samples with cold plasma technology and carnosine could inhibit growth of the bacteria in the treated meat samples. Of 31 chemicals tested, phenylethylamine, α-d-lactose, d,l-α-glycerol phosphate, 2-hydroxybenzoic acid, γ-hydroxybutyric acid, α-ketobutyric acid, and d-malic acid could not be metabolized by bacteria in the meat samples. Future research is required to determine whether these seven chemicals that inhibited growth of bacteria in these meat samples can be used as food preservatives for extending the shelf life of these products. Whether the bacterial flora can be an indicator of effectiveness for meat samples treated with cold plasma, carnosine, or both needs further study.

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The effect of atmospheric pressure cold plasma on the inactivation of Escherichia coli in sour cherry juice and its qualitative properties

One of the nonthermal methods is the atmospheric pressure cold plasma (APCP). In this study, the effect of cold plasma on the reduction of Escherichia coli bacteria and qualitative properties of sour cherry juice, including total phenolic content (TPC), total anthocyanin content (TAC), and vitamin C, were investigated. Independent variables included plasma exposure time (1, 5, and 9 min), applied field intensity (25, 37.5, and 50 kV/cm), feeding gas oxygen content (0%, 0.5%, and 1%), and sample depth (0.5, 1, and 1.5 cm). The results show that increased oxygen content in argon has the greatest effect on the reduction of bacteria, and plasma exposure decreased 6 logarithmic periods of E. coli bacteria in sour cherry juice. Optimization results showed when all bacteria were eliminated by plasma, TPC remained unchanged, and TAC and vitamin C decreased by 4% and 21%, respectively, while thermal methods increased TPC by 23% and decreased TAC and vitamin C by 26% and 77%, respectively. These results indicate that, compared with conventional thermal methods, sour cherry juice pasteurization using APCP has little effect on the juice qualitative properties, and this method can serve as a suitable alternative to conventional thermal methods.

The effect of rosemary Extract and cold plasma treatments on bacterial community diversity in poultry ground meats

To provide safer food, many technologies have been used to preserve food. One such technology is cold plasma, which can reduce viable bacterial counts in various food matrices. However, bacterial communities in food matrices before and after cold plasma treatment have not been investigated. In this communication, the EcoPlates™ were used to physiologically profile bacterial communities from poultry ground meat treated with rosemary, cold plasma or both. The cultures in the plates were incubated at 25 °C for seven days in an OmniLog® system. Responses of the bacterial communities to 31 chemicals were measured on formazan production. The results show that the three parameters of the Gompertz growth curves were observed in all samples, 2-hydroxybenzoic acid could not be used, while pyruvic acid methyl ester was used for a carbon source by the bacterial communities from all meat samples, each bacterial community metabolized different numbers of chemical compounds at different rates, and reduction of bacterial functional diversity was observed in the poultry meat samples treated with cold plasma and rosemary. In the future, investigations on whether the physiological profiling in bacterial communities be used as an indicator for effectiveness of cold plasma treatment of meat samples.