The Meat and its products are excellent sources of the nutrients for the humans. The Meat and its products also provide a favorable environment for the microbial growth. To prevent the microbiological contamination of the livestock foods, the chemical preservatives, including the nitrites, the nitrates, and the sorbates, have been widely used in the food processing due to their low cost and the strong antibacterial activity. The application of the chemical preservatives is recently being considered by the customers due to the concerns related to the negative health issues. The demand for the natural substances as the food preservatives has increased with the use of the plant origin and the animal origin products, and the microbial metabolites. The natural preservatives inhibit the growth of the spoilage bacteria or the foodborne pathogenic bacteria by increasing the permeability of the microbial cell membranes, the interruption of the protein synthesis, and the cell metabolism. The Natural preservatives can extend the shelf life and inhibit the growth of the bacteria. The natural preservatives  can influence the food sensory properties, including the food flavor, the food taste, the food color, the food texture, and the food acceptability.In order  to increase the applicability of the natural preservatives, a number of the strategies, including the combinations of different preservatives or the food preservation methods, such as the active packaging systems and the encapsulation, have been used for the applications of the natural preservatives in meat and its products.

The Foodborne pathogenic bacteria, including the Listeria monocytogenes, the Staphylococcus aureus, the pathogenic Escherichia coli, the Clostridium perfringens, the Campylobacter spp., and the Vibrio spp., cause a large number of the illnesses, with substantial damage to the human health and the economy. The World Health Organization (the WHO), the food contaminated with the foodborne pathogenic bacteria, the chemicals, and the allergens results in 600 million cases of the foodborne illness and four hundred thousand deaths worldwide/ year, Moreover, fifty-six million people die /year and 7.7% of people worldwide suffer from the foodborne diseases. The Meat and its products are essential nutrient sources for the humans due to their excellent protein content, the essential amino acids, the vitamin B groups, and the minerals. The meat and its products also provide an appropriate environment for the spoilage bacteria or the foodborne pathogenic bacteria due to their high-water activity and the nutrient factors (1,2,3,4,5,6 and 7). The food processing has advanced worldwide, resulting in an enhanced the threat of the food contamination by the pathogenic bacteria, the chemical residues, the harmful food additives, and the toxins. The multiplication of the spoilage and the pathogenic bacteria should be controlled to ensure the food safety. The food preservation techniques for protecting the food from the pathogenic bacteria and extending the shelf-life include the chemical methods, such as the use of the preservatives; the physical methods, such as the heat treatment, the drying, the freezing, and the packaging; and the biological methods using the bacteria that have an antagonistic effect on the pathogenic bacteria and produce the bacteriocins. Among them, the addition of the food preservatives that inhibit the growth of the bacteria is a widely used the food protection technique. The countries in the world have different regulations for the food preservatives (8,9,10,11,12,13 and 14). The chemical preservatives have the advantage for the meat production due to the low cost, guaranteed the antibacterial effect or the shelf-life extending activity, and the little effect on the meat taste, the meat flavor, the meat color, and the meat texture. The chemical preservatives tend to be less preferred by the consumers because of a number of health concerns regarding their side effects. The food consumers selected preservatives as the most concerned food additive owing to their negative effects on the health. The Sorbic acid, the benzoic acid, and their salts promote the mutagenic and the carcinogenic compounds. The Nitrites and the nitrate, used as preservative and coloring agents in the meat, have been associated with the leukemia, the colon cancer, the bladder cancer, and others. The Natural preservatives have emerged as alternatives to the chemical preservatives. The Natural preservatives have shown potential to provide the effective antimicrobial activity while reducing the negative health effects. The Meat and its products containing the chemical additives, are a major concern for the public health. The meat processors and the researchers have begun to consider the use of the natural rather than the chemical preservatives (15,16,17,18,19,20 and 21). The ‘clean label’ food trends, including the meat and its products, began and possessed an important source of the food marketing. It includes the consumer, friendly characteristics, such as the chemical additive free, the least processing, a brief list of the food ingredients, and the procedure of the traditional methods. The clean label food material market, including the natural preservatives, is likely to value, mostly owing to growing consumer requests for all the natural products. The natural preservatives such as the nisin, the natamycin, the ε-polylysine, and the grapefruit seed extract are registered, but they are not approved for the meat products, or their concentration is not specified. The replacement of chemical preservatives with the natural preservatives has major positive effects and is being accepted by the customers. The food producers also encounter challenges, including a decrease in price competitiveness due to the relatively high price of the natural preservatives and a decrease in the antibacterial effect due to the food ingredients, such as the carbohydrates, the proteins, and the lipids. In the case of the plant origin substances, the standardization is problematic because of the influence of the country of origin, the soil, and the harvest seasons. The toxicity evaluation or identification of exact compounds for several plant origin compounds contained in extracts and the essential oils have been performed. To solve these problems, various studies have been conducted to optimize the extraction process, combine other antimicrobial substances, apply active packaging, and encapsulate antibacterial substances to improve their utilization (22,23,24,25, 26, 27 and 28). 

This review summarizes the current knowledge about the application of the natural preservatives for the meat and its products against the foodborne pathogenic and the spoilage bacteria.

The Application Technique of the Natural Preservatives to the Meat and its Products

The Natural preservatives are manufactured in a variety of formulations including powder formed by drying methods and liquid forms such as essential oils. The Natural preservatives are directly added to the meat products and extend the shelf life by inhibiting the bacterial growth. It is possible to increase the antibacterial effect of the natural preservatives through a combination of the other food processing methods (29,30,31,32,33,34 and 35). In the case of the plant origin natural preservatives, it is necessary to consider the form applied to the food. The Natural preservatives are commonly prepared in the form of extracts using organic solvents, water, and essential oils. The plant extracts obtained from rosemary, chestnut, sage, cranberry, oregano, grape seed, and others have been used as the meat preservatives. The application of the plant origin substances to the meat products in the form of the essential oil because the antibacterial effect of essential oil type is better than that of extract type. It is difficult to apply large amounts of the essential oil to the food because of its distinct organoleptic properties. The Recent developments have attempted to solve this problem by applying essential oils with other antibacterial substances. The advantage of this application is that it reduces the amounts of essential oils with strong flavor and increases antioxidant and antibacterial effects through synergistic effects. In terms of industrial perspective, if the chemical preservatives cannot be completely replaced with the natural preservatives, due to the industrial problems, such as increasing the economic costs or the complexity of the product manufacturing process, they could be replaced gradually by composing a mixed formulation of the chemical preservatives and the natural preservatives (36,37,38,39, 40,41 and 42). The gamma irradiation and the high-pressure processing (the HPP) treatment are the physical food-processing methods that can further increase the antibacterial efficacy of the natural preservatives. The Unlike thermal food processing, these two food processing techniques could be used for the pasteurization of the raw meat because it has a minor effect on the food composition. In 1997, the WHO, the Food and Agricultural Organization (FAO), and the International Atomic Energy Agency (the IAEA) concluded that foods processed in the proper doses of the irradiation are nutritionally sufficient and safe to consume. The irradiation is permitted for the food preservation in more than sixty countries. Recent approaches in the food irradiation have involved the use of combined treatments with the natural preservatives to reduce irradiation doses. The gamma irradiation of medium doses (2–6 kGy) with the natural compounds and active packaging has been applied to extend the shelf-life of the meat and its products. The HPP is also a non-thermal technique for the food preservation that inhibits the growth of the bacteria and maintains the natural properties of the food. The HPP is performed under high pressures (100–800 MPa) at the mild temperature or the weak heating. The potential capability of combining the HPP and the natural preservatives including the essential oil and the antibacterial peptides in alleviating both the processing conditions of the HPP and the concentration of the natural preservatives while maintaining antibacterial effects (43,44,45,46,47,48 and 49). The Encapsulation is one of the effective approaches for expanding the applicability of the natural preservatives to the food. The encapsulation was performed with GRAS (generally recognized as safe) materials such as the alginate, the chitosan, the starch, the dextrin, and the proteins using the various techniques including the spray-drying, the extrusion, the freeze-drying, the coacervation, and the emulsification. The application of the natural preservatives to the meat is limited due to their characteristics, such as low solubility and the bioavailability, the rapid release, and the easy degradation. The environmental conditions, such as the pH, the storage temperature and the time, the oxygen and the light exposures could influence the efficacy of the natural preservatives. Through the encapsulation, the natural preservatives, especially hydrophobic compounds (e.g., the essential oil), could improve its stability and expand the versatility of the food processing while maintaining the antibacterial effect (50,51,52,53, 54,55 and 56). The Active packaging is an innovative packaging technology that allows for an interaction with the product and its environment to extend the shelf-life and to ensure its microbial safety while keeping the original properties of the packaged food. In relation to the European Union Guidance to the Commission Regulation, active packaging is a type of the food packaging with a further beneficial function, while providing a protective barrier against the external influence. In the meat processing, the antimicrobial active packaging could be applied in several methods which are the incorporation of the natural preservatives into a sachet inside the packaging, the packaging film composition with the natural preservatives, the packaging coated with the natural preservatives onto the surface of the food, and use of the antimicrobial polymers as the packaging materials (57,58,59,60,61,62 and 63). The application of the microorganism origin natural preservatives, known as the bio-preservation, in which the useful bacteria or their antibacterial substances have antagonistic effects on the pathogenic or the spoilage bacteria, are used is also a meat preservation method in the spotlight. This method is mainly involved in the lactic acid bacteria, the Lactobacillus spp., the Leuconostoc spp., the Pediococcus spp., and the Lactococcus spp., that have a GRAS status, widely participate in the fermentation processes, and produce the various antibacterial metabolites such as the organic acids, the hydrogen peroxide, and the bacteriocins. In terms of the application to the meat products, the bio-preservation methods included the direct inoculation with the lactic acid bacteria, which has an inhibitory effect on the spoilage or the pathogenic bacteria, the inclusion of the bacterial strains producing the antimicrobial substances in the fermentation starter, and the treatment with the purified bacteriocins (64,65,66,67,68,69 and 70).

The Natural Preservatives from the Plants and Their Application for the Meat and its Products

The antibacterial effect of the plant origin natural preservatives is closely related to the polyphenols, the phenolics, and the flavonoids. The Plant origin polyphenols have various classifications and structures, as the phenolic acids (the caffeic acid, the rosmarinic acid, the gallic acid, the ellagic acid, the cinnamic acid), the flavones (the luteolin, the apigenin, the chrysoeriol), the flavanols (the catechin, the epicatechin, the epigallocatechin, the gallocatechin, and their gallate derivatives), the flavanones (the hesperidin, the hesperetin, the heridictyol, the naringenin), the flavonols (the quercetin, the kaempferol, the myricetin), the isoflavones (the geinstein, the daidzin, the formononetin), the coumarins (the coumarin, the warfarin, the 7-hydroxycourmarin), the anthocyanins (the pelagonidin, the delphinidin, the cyanidin, the malvidin), the quinones (the naphthoquinones, the hypericin), the alkaloids (the caffeine, the berberine, the harmane), and the terpenoids (the menthol, the thymol, the lycopene, the capsaicin, the linalool) (71,72,73,74,75,76 and 77). The Polyphenols have been recognized for their effective antimicrobial properties. Although the antimicrobial mechanism has not yet been clearly elucidated, the cell membrane-disturbing molecules, such as the hydroxy group (OH-), which induces the leakage of intracellular components, inactivation of metabolic enzymes, and extinction of the adenosine triphosphate (the ATP) structure; direct pH change in the environment by the improvement in proton concentration, reduction of the intracellular pH by separation of acid molecules, and modification of the bacterial membrane permeability; an organic acid in the plant extracts may influence the oxidation of the nicotinamide adenine dinucleotide (the NADH), the eliminating, the reducing agent used in the electron transport system (78,79,80,81,82,83 and 84).

The Rosemary

The Rosemary (the Rosmarinus officinalis L.) is a perennial herb with the woody, the aromatic, and the evergreen needle-like leaves. Originally from the Mediterranean region, it is broadly distributed throughout the globe. The Rosemary has been used as a spice and the flavoring agent in the food. The Rosemary essential oil is known to contain fifteen kinds of the bioactive compounds. The principal compound was 1,8-cineole (35.32%). Other major compounds were the camphor, the α-pinene, the trans-caryophyllene, the α-thujone, and the borneol (85,86,87,88,89,90 and 91). The antibacterial effect of the rosemary ethanol extracts against the Listeria monocytogenes in the beef. The application of 45% rosemary ethanol extract for the Listeria monocytogenes on the beef led to a two-log colony forming unit / gram reduction in the incubation at 4 °C for nine days. In the chicken meat, the effect of the rosemary essential oil on the inhibition of the Salmonella Enteritidis and the spoilage protective effects at 4 and 18 °C was investigated. The 5 mg/mL of the rosemary essential oil induced the decrease in the coliform, the aerobic bacteria, the lactic acid bacteria, and the anaerobic bacteria at 18 °C for one day. The Comparing with the untreated chicken meat, the reductions of 1.75 log Colony Forming Unit / gram (the coliform), 0.87 log Colony Forming Unit / gram (the aerobic bacteria), 1.05 log Colony Forming Unit / gram (the lactic acid bacteria) and 1.28 log Colony Forming Unit / gram (the anaerobic bacteria) were observed in the group treated with rosemary essential oil at 18 °C. The Rosemary oil reduced the S. Enteritidis by more than two log Colony Forming Unit / gram at 18 °C, but less than one log Colony Forming Unit / gram at 4 °C (92,93,94,95,96,97 and 98). The rosemary essential oil applied with modified atmosphere packaging for the inhibition of the foodborne pathogenic bacteria (the S. Typhimurium and the Listeria monocytogenes) in the poultry filets under the refrigerated conditions for seven days was examined. The 0.2% rosemary essential oil did not affect the sensory profile and inhibited the growth of both the pathogenic bacteria in the laboratory media within one day. The Treatment with 0.2% rosemary essential oil did not affect the reduction in the S. Typhimurium, but showed weak antibacterial activity against the Listeria monocytogenes until the first day of the storage (0.1 log Colony Forming Unit / gram the reduction compared to the control) (99,100,101,102,103,104 and 105).

The Sage

The Sage (the Salvia officinalis L.), belonging to the Lamiaceae family, has been used since prehistoric eras because of its flavor, taste, therapeutic, and preservative properties. The Sage is known to contain considerable amounts of the rosemary acid, the p-coumaric acid, and the benzoic acid. The Sage essential oils, the camphor, the carvacrol, the R (+) limonene, and the linalool are the major components in terms of content (106,107,108, 109,110 and 111). The antibacterial effects of various sage preparations were assessed for low-pressure mechanically separated meat in vacuum packaging stored at −18 °C for nine months. The mechanically separated meat from the chickens with the addition of the sage extracts inhibited the growth of all groups of the bacteria (the mesophilic aerobic bacteria, the psychrotrophic bacteria, the Enterobacteriaceae, the coliforms, and the enterococci). The most effective antibacterial effect was exhibited by the 0.1% sage essential oil-treated groups (112,113,114,115,116 and 117). The antibacterial effect of the sage essential oil (0.625%) on the survival of the Listeria monocytogenes in the Sous-vide cook-chill beef stored in the refrigerated storage (2 or 8 °C) for 28 days. The decrease of one log Colony Forming Unit / gram of the Listeria monocytogenes was detected in the sage essential oil-treated groups compared to the control at 2 °C. Although the exponential growth was observed from the day 14, decrease the Listeria monocytogenes counts of one log Colony Forming Unit / gram were detected in the sage essential oil treated samples stored at 8 °C (118,119,120,121,122 and 123).

The Thyme

The Thyme (the Thymus vulgaris) is a representative herb used together with the meat and its products. The application of the thyme in the meat products can elevate the antioxidant, the antibacterial, the shelf-life extension, and the sensory properties. In the meat sausage, the thyme essential oil inhibited 2.69 log Colony Forming Unit / gram of coagulase-positive Staphylococcus and 4.41 log Colony Forming Unit / gram of aerobic mesophilic bacteria, respectively, at a concentration of 0.95% by mixing with 1% (w/w) powdered beet juice. The sensory properties, odor, flavor, and overall acceptability improved (124,125,126,127,128 and 129). The 1% thyme oil led to the reduction in the S. enterica by three log Colony Forming Unit / gram during the margination process with lemon juice and 0.5% Yucca schidigera extract in the raw chicken breast. The major composition of the thyme oil revealed 51.1% and 24.1% thymol and O-cymene, respectively. The antibacterial effects of thyme may be due to additive or synergistic effects with its major and/or minor components. The Thymol and its synergistic effect with other phenolic compounds, such as the carvacrol, the p-cymene, and the γ-terpinene, can change the permeability of the bacterial cell wall, leading to cell death (130,131,132,133,134 and 135). The Thyme essential oil encapsulated with the casein and the maltodextrin was evaluated for its antibacterial potential in the vitro and in the situ (the hamburger-like meat products). The encapsulated thyme essential oil showed the same minimum inhibitory concentration (0.1 mg/mL) against the Escherichia coli, the S. Typhimurium, the Staphylococcus aureus, and the Listeria monocytogenes as that of the unencapsulated thyme essential. In the treated groups with 1% (v/v) of the encapsulated thyme essential oil for the meat, the Escherichia coli counts were decreased from 23 most probable number (the MPN)/ gram to 0 MPN/ gram, which was similar to the conventional preservative (the sodium nitrate) used as a control until 14 days of the refrigerated storage (4 °C) (136,137,138,139,140 and 141).

The Oregano

The Oregano (the Origanum vulgare) is regularly used in the Mediterranean foods. The oregano essential oil has recognized antibacterial and antioxidant properties for the extension of the shelf-life. The antibacterial effects of the oregano were due to two bioactive the polyphenols, the thymol and the carvacrol (142,143,144,145,146 and 147). The oregano essential oil and its effect on the shelf life of the black wildebeest Biceps femoris muscles was investigated at 2.6 °C. The components of the oregano oil were the thymol, the carvacrol, the ρ-cymene, the β-caryophyllene, the γ-terpinene, the α-humulene, and the α-pinene; among them, the carvacrol (42.94%) and the thymol (17.40%) were the highest. The total viable counts and the lactic acid bacteria reached the spoilage limit (seven log Colony Forming Unit / gram) after three days. The growth rates for the total viable counts and the lactic acid bacteria in the treated group were 40% higher than those in the untreated groups (148,149,150,151,152 and 153). The combinatorial effect of the oregano essential oil with the caprylic acid was studied in the vacuum-packed minced beef. The addition of 0.2% oregano essential oil with 0.5?prylic acid and 0.1% citric acid in the minced beef reduced the counts of the lactic acid bacteria by 1.5 log Colony Forming Unit / gram in vacuum packaging. The cell counts of the psychrotrophic bacteria and the Listeria monocytogenes were reduced by more than 2.5 log Colony Forming Unit / gram at 3 °C for 10 days. The Oregano essential oil inhibits the growth of the bacteria by releasing volatile components during the drying process. The addition of the oregano essential oil composed of the carvacrol (64.5%), the p-cymene (5.2%), and the thymol (2.9%) inhibited the S. Enteritidis and the Escherichia coli in the beef drying process. For drying, a filter paper was soaked with oregano essential oil and placed in front of the fan of the drier. The beef samples were dried at 55 °C for 6 hours. Both the bacteria (the S. Enteritidis and the Escherichia coli) were not detected after treatment with three mL of oregano essential oil (154,155,156,157,158 and 159).

The Chestnut

The Castanea crenata was classified into the Castanea family and is a woody plant native to the East Asia, including the Korea and the Japan. The Castanea sativa is one of the most important Castanea families and the food resources of the European areas for long periods. Chestnut shells contain abundant phenols and hydrolyzable tannins. The chestnut inner shell extracts using ethanol exhibited antimicrobial effects against C. jejuni in the chicken meat at a concentration of two mg/mL. The polyphenol and flavonoid contents of chestnut inner shell ethanol extracts were 532.96 ± 3.75 mg gallic acid/100 g and 12.28 ± 0.03 mg quercetin/100 g, respectively (160,161,162,163,164 and 165). The influence of the chestnut extracts (the Castanea sativa) on the leaf, the bur, and the hull of the beef patties under refrigerated conditions (2 ± 1 °C) for 18 days to extend the shelf-life. Inside the chestnut extracts from the leaf, the bur, and the hull, only the leaf extract at a concentration of 1000 mg/kg had weak antimicrobial activity. The lactic acid bacteria and the Pseudomonas spp. were reduced by 0.37 log Colony Forming Unit / gram and 0.33 log Colony Forming Unit / gram at seven days, respectively (166,167,168,169,170 and 171).

The Grapefruit Seed Extract 

The Grapefruit Seed Extract is a byproduct of the Citrus paradise. The Grapefruit Seed Extract contains the various phenolic compounds and the flavonoids, such as the catechin, the citric acid, the naringenin, the procyanidin, and the epicatechin gallate. The Grapefruit Seed Extract has been described to have a wide-ranging spectrum antimicrobial, the antiparasitic, and the antifungal activities. The Polyphenols in the Grapefruit Seed Extract are unstable but can be chemically modified to become more stable using quaternary ammonium compounds, such as the benzethonium chloride, during the industrial procedure of the commercial Grapefruit Seed Extract preparations (172,173,174,175,176 and 177). The bacteriostatic effect of the commercial Grapefruit Seed Extract (the Citricidal) on the sous-vide chicken products against the Clostridium perfringens. The cell numbers of the Clostridium perfringens were consistently 2.5 log Colony Forming Unit / gram regardless of the treatment or the control groups until 9.5 h of stored at 19 °C; the storage of the control and 50 or 100 ppm Grapefruit Seed Extract treated groups at 25 °C for more than six hours resulted in fast growth rates of the Clostridium perfringens, showing 2–3 log Colony Forming Unit / gram. The Grapefruit Seed Extract concentrations at 200 ppm inhibited the growth of the Clostridium perfringens stored at 19 and 25 °C. The active packaging system for the inhibition of the foodborne pathogenic bacteria used the mixed natural preservatives consisting of the Grapefruit Seed Extract (80 mg/m2) with the cinnamaldehyde (200 mg/m2) and the nisin (60 mg/m2) was assessed for the beef storage. The active packaging showed decrease the counts of the psychrotrophic and the anaerobic bacteria compared to the control groups at 1–2 log Colony Forming Unit / gram. The packaged beef samples with mixed natural preservatives showed a decrease in the Listeria monocytogenes, the Staphylococcus aureus, and the C. jejuni for 4.7 log Colony Forming Unit / gram, 0.81 log Colony Forming Unit / gram, and 3.1 log Colony Forming Unit / gram compared to wrapped packaging at 28 days of the refrigerated storage, respectively. The C. jejuni was observed below the detection limit after 21 days of the storage (184,185,186,187,188 and 189)

The Cinnamon

The Cinnamon is a native plant in Asia that is acquired from the inner bark of the genus Cinnamomum. The Cinnamon contains several active compounds, such as the cinnamaldehyde, the eugenol, the cinnamyl acetate, the L-borneol, the β-caryophyllene, the caryophyllene oxide, the camphor, the L-bornyl acetate, the α-terpineol, the α-cubebene, the α-thujene, and the terpinolene. The cinnamon (Cinnamomum cassia) essential oils could inhibit the L. monocytogenes in the ground beef at the refrigerated (0 and 8 °C) and the frozen (–18 °C) conditions. The concentration of five percentage cinnamon essential oil to decrease by 3.5–4.0 log Colony Forming Unit / gram of Listeria monocytogenes at 0 and 8 °C for seven days. Under the frozen conditions, the Listeria monocytogenes was reduced by 3.5–4.0 log Colony Forming Unit / gram over 60 days. The antibacterial effect and the shelf-life extending activity were evaluated using a chitosan edible coating containing 0.6% cinnamon essential oil on the roast duck slices under the modified atmosphere packaging (30?rbon dioxide (CO2)/70% nitrogen (N2)) at the storage at 2 ± 2 °C for 21 days. The edible coating with cinnamon essential oil showed the total viable counts reduced by one log Colony Forming Unit / gram compared to the control after 14 days of the storage. It is similar to the results of the Enterobacteriaceae counts. The number of the lactic acid bacteria was decreased than that of the control until the day 7 of the storage, but there was no significant difference from day 11 of the storage. The growth of the Vibrio spp. was delayed using the edible coating with the cinnamon essential oil within the earlier period of the storage as a result of the microbial diversity sequencing (196,197,198, 199, 200 and 201).

The Turmeric

The Turmeric (Curcuma longa L.) has long been used as a flavor and the color agent in the food and the traditional medicine to treat the various diseases, mainly in the South and East Asia. The main active compounds of the turmeric originate from its constituents, called the curcuminoids. The Curcuminoids (the curcumin, the demethoxycurcumin, and the bis-demethoxycurcumin) content of the turmeric varies between about 2–9?sed on its growth environments, such as the cultivar, the soil, and the climatic conditions. The antibacterial effect of the turmeric on the chicken breast meat was assessed for the Escherichia coli and the Staphylococcus aureus stored at 4 °C for two days. When 1% turmeric powder was added, no difference in the Staphylococcus aureus counts was observed between the turmeric treated and the control groups. In the case of the Escherichia coli, a reduction of 0.2 log Colony Forming Unit / gram was observed, but this was not statistically significant (202,203,204,205, 206 and 207). The chicken meat was treated with the turmeric powder and the gamma irradiation to improve the meat quality and stability. The total aerobic bacteria and the coliforms were completely decontaminated with 3% turmeric powder and 2 kGy of the gamma irradiation at 4 °C for 14 days. The microbial characteristics of the edible coatings using the turmeric starch and the bovine gelatin were examined in the frankfurter sausages. The edible coating was developed with a 5% (w/w) aqueous solution of the turmeric starch and the gelatin. The microbial growth of the coated sausages stored at 5 °C for 20 days decreased by 2.21, 1.01, and 1.65 log Colony Forming Unit / gram for the mesophilic bacteria, the lactic acid bacteria, and the psychotropic bacteria, respectively. At 10 °C, the decreases were 1.57, 2.14, and 1.99 log Colony Forming Unit / gram for the mesophilic bacteria, the lactic acid bacteria, and the psychotropic bacteria, respectively (208,209,210,211,212 and 213).

The Plant origin Antimicrobial Peptides

The Plant origin the Antimicrobial Peptides have been studied for their potential to inhibit the different pathogenic bacteria, including the food spoilage bacteria, the food poisoning bacteria, the mold, and the yeast species. The antibacterial peptide Leg1 from the chickpea legumin were reported in the meat application of the plant origin the Antimicrobial Peptides. The Raw pork was pretreated with Leg1 and inoculated with the Escherichia coli and the B. subtilis. The bactericidal activity was measured at 37 °C for 16 hours. The minimum bactericidal concentrations of Leg1 on the pork were 125 µM and 15.6 µM for the Escherichia coli and the B. subtilis, respectively. This was the same concentration as the MBC of the nisin, the bacteriocin from the Lactococcus lactis, for the tested strains. The Antimicrobial Peptides from pea (the 11SGP) and the red kidney bean (the RBAH) were used to extend the shelf life of the raw buffalo meat. In the laboratory media, the Gram positive (the L. monocytogenes, the B. cereus, and the Streptococcus pyogenes) and the Gram-negative (the Escherichia coli, the Pseudomonas aeruginosa, the Acinetobacter baumannii) bacteria were inhibited by 11GSP (60 µg/mL) and the Gram-negative bacteria by 60% and the Gram-positive bacteria by 90%. RBAH (60 µg/mL) alleviated the growth of the Gram-negative bacteria by 56% and the Gram-positive bacteria by 85%. In the buffalo meat, the counts of the mesophilic bacteria of 11SGP (400 µg/ gram) and the RBAG (400 µg/ gram) treated groups decreased by 1.60 log Colony Forming Unit / gram and 1.94 log Colony Forming Unit / gram compared to the control groups. The psychrophilic bacteria, 11SGP and the RBAG reduced by 1.10 log Colony Forming Unit / gram and 1.47 log Colony Forming Unit / gram, respectively, after 15 d of the refrigerated storage (4 °C) (172,173,174,175 and 176).

The Natural Preservatives from the Animals and Their Application for the Meat and its Products

The Various antibacterial systems of the animal sources are associated with the defense mechanisms against external intruders. The preservatives derived from the animal sources include the lysozymes, the lactoferrin, the ovotransferrin, the lactoperoxidase, the Antimicrobial Peptides from the livestock animals, and the polysaccharides. The Lysozyme can suppress several Gram-positive bacteria because of the Lysozyme distinctive ability to injure bacterial membranes by hydrolyzing the 1,4-β-linkage between the N acetyl D glucosamine and the N acetyl muramic acid of the peptidoglycan in the bacterial membrane. The Peptide based antibacterial substances containing the Antimicrobial Peptides from the animal sources, the ovotransferrin, and the lactoferrin could influence the cell membranes or the synthesize Antimicrobial Peptides, the peptides, and the enzymes. The antibacterial mechanism of the Antimicrobial Peptides due to the attachment to the bacterial cell membrane and disturb its integrity, resulting in the cell lysis. The Antimicrobial Peptides may also exert more complex activities that inhibit the metabolic and the translational systems. The ovotransferrin isolated from the eggs increased the cell membrane permeability of the Gram positive and the Gram-negative bacteria. The ovotransferrin destroyed the cell membrane integrity, increased the permeability of the pathogen membranes, and induced morphological changes. The Lactoferrin has antibacterial effects related to the large cationic patches present on the surface and the iron impoverishment. The Lactoferrin has an antibacterial effect only when in its iron free state and the iron saturated lactoferrin has a limited antimicrobial activity. The Lacroperoxidase oxidizes the sulfhydryl groups of the proteins present in the bacterial membrane, which could be injured by the efflux of the potassium ions, the amino acids, the peptides, and the enzymes (177,178,179,180,181 and 182).

The Lysozyme

The Lysozyme (the muramidase or the N acetyl muramichydrolase) is mainly extracted from the hen egg whites and is known as an antimicrobial enzyme. The Lysozyme is a glycoside hydrolase that hydrolyses the linkages in the peptidoglycan at the Gram-positive bacterial cell wall. The Lysozyme is composed of 129 amino acids, which contain the disulfide bonds and the tryptophan, the tyrosine, and the phenylalanine residues. The Lysozyme has been used commercially, named the Inovapure, against the spoilage and the foodborne pathogenic bacteria to prolong the shelf life of the raw and the processed meat. The Modified lysozyme, the high hydrophobicity, and the low hydrolytic activity compared to the lysozyme monomer, at the concentrations of 5%, exhibited low microbial growth rates (the total viable count 4.59 log Colony Forming Unit /cm2; the molds and the yeasts 2.17 log Colony Forming Unit /cm2) in the pork surface with the modified atmosphere packaging with composites of 50% O2, 40% CO2, and 10% N2 . The mixed antimicrobials consisting of the lysozyme (250 ppm), the nisin (250 ppm), and the disodium ethylenediaminetetraacetic acid (the EDTA) (20 mM) had antibacterial effects against the Listeria monocytogenes, the total viable counts, the Enterobacteriaceae, the Pseudomonas spp., and the lactic acid bacteria in the ostrich meat patties with the air and the vacuum packaging. The mixed lysozyme preparations reduced the Listeria monocytogenes below the official detection limit of the European Union (<2>

The Ovotransferrin

The Egg white contains 13% ovotransferrin (the conalbumin), which is a monomeric 77.9 kDa glycoprotein comprised of 686 amino acid residues. The ovotransferrin contains N and C globular parts, each of which can reversibly Fe3+ and CO32− . The ovotransferrin is the main constituent of the egg’s defense system for the bacteria, as it renders the iron unusable for the microbial growth within the albumen. The antimicrobial effects of the ovotransferrin against the Escherichia coli in the fresh chicken breast involved in κ carrageenan film. The growth of the Escherichia coli in the fresh chicken breast wrapped with the active film was 2.7 log Colony Forming Unit / gram by the addition of 25 mg of the ovotransferrin in combination with 5 mM EDTA. The ham models, 25 mg/mL of ovotransferrin with 100 mM sodium bicarbonate (NaHCO3) did not show any antibacterial effects against the Escherichia coli O157:H7 and the Listeria monocytogenes in commercial hams, whereas 25 mg/mL ovotransferrin with half percentage citric acid had bacteriostatic effects against Listeria monocytogenes (188,189,190,191,192 and 193).

The Lactoferrin

The Lactoferrin, a glycoprotein that belongs to the transferrin protein family in the milk and the milk products as well as the neutrophil granules and exocrine secretions in the mammals, was able to bind the iron within the cells. The ability of this 80 kDa protein to control free iron levels contributes to its bacteriostatic and the health beneficial characteristics, such as stimulating bone growth, protecting the intestinal epithelium, and promoting the immune system in animals. In the ground beef, application of the active lactoferrin, the immobilized lactoferrin with the glycosaminoglycans, and solubilized in the citrate/bicarbonate buffer systems at concentrations of three percentage and five percentage resulted in two log Colony Forming Unit / gram reductions of Escherichia coli O157:H7 at 10 °C for nine days. The reduction of the S. Enteritidis growth was 0.8 log Colony Forming Unit / gram when the active lactoferrin concentration was increased to two-point five percentage. A single application of half percentage active lactoferrin reduced Listeria monocytogenes in the beef, resulting in two log Colony Forming Unit / gram. The Bovine lactoferrin (half mg) was tested against the Escherichia coli O157:H7 and P. fluorescens inoculated on the chicken with HPP treatments between 200 and 500 MPa for 10 min at 10 °C. As a result, the P. fluorescens was decreased when the lactoferrin was combined with the HPP treatment at 300 MPa for 2.3 log Colony Forming Unit / gram additional reduction compared to only 300 MPa treatment on day 9. Additional reductions in the Escherichia coli O157:H7 counts obtained by combined treatments remained below 0.5 log Colony Forming Unit / gram. (194,195,196,197 and 198)

The Lactoperoxidase

The Lactoperoxidase is a member of the peroxidase family. It is a ubiquitous active enzyme in bovine milk, which has antimicrobial effects. Bovine lactoperoxidase is a glycoprotein that contains a peptide chain of 78.4 kDa and catalyzes the oxidation of thiocyanate ions (SCN) in lactoperoxidase, producing oxidizing products, such as hypothiocyanite and hypothiocyanous acid. The lactoperoxidase coated with alginate at concentrations of 2, 4, and 6% on the shelf life of the chicken breast filets. The chicken samples with active coating of alginate and 6% lactoperoxidase showed a reduction of the Enterobacteriaceae, the P. aeruginosa, and the aerobic mesophilic bacteria by five log Colony Forming Unit / gram, 4 log Colony Forming Unit / gram, and 2.5 log Colony Forming Unit / gram at 16 days of the refrigerated storage, respectively. The antimicrobial effects of the lactoperoxidase were also assessed against the Listeria monocytogenes and the S. Enteritidis in the sliced dry cured ham for 60 d at 8 °C treated with the HPP at 450 MPa. The synergistic effect of lactoperoxidase and pressure was confirmed as the S. Enteritidis decreased below the detection limit (one log Colony Forming Unit / gram). The Listeria monocytogenes, the synergistic effect reduced cell viability by 0.86 log Colony Forming Unit / gram compared with the untreated samples at the end of the storage. In the beef, the effect of the lactoperoxidase on the growth of the inoculated pathogenic bacteria (four log Colony Forming Unit / gram) composed of the Staphylococcus aureus, the Listeria monocytogenes, the Escherichia coli O157:H7, the S. Typhimurium, the P. aeruginosa, the Yersinia enterocolitica, and the indigenous microbiota was investigated. The pathogenic bacteria used in the experiment were reduced compared to the control at a chilling regime (−1 to 12 °C) for 42 days. The total aerobe and the Pseudomonas spp. increased less in the lactoperoxidase treated group than in the control group, but the antibacterial effect was not exhibited for anaerobes and the lactic acid bacteria (199,200,201,202 and 203).

The Livestock Animal origin

The Livestock animal origin products have been used as a source of the Livestock animal origin products. Among these byproducts of the livestock, the blood, the bones, the collagen, the gelatin, the liver, the lungs, the placenta, the skin, and the visceral mass are important sources of the Livestock animal origin products, as well as the muscle parts. The bovine cruor, a slaughterhouse byproduct containing mainly hemoglobin, broadly described as a rich source of fibrin proteins, was investigated for the extraction of the Livestock animal origin products. The faction named α137–141 (polypeptide with five components, Thr Ser Lys Tyr Arg), a small (0.65 kDa), and hydrophilic Livestock animal origin products deviated from hemoglobin. The α137–141 preservative (0.5%, w/w) had bacteriostatic effects on the total microbial population, coliform bacteria, the yeasts, and the molds at 4 °C for 14 d on the beef. The Livestock animal origin products isolated from porcine leukocytes had antibacterial effects on the proliferation of Staphylococcus aureus and Escherichia coli inoculated in the ground meat (the boneless ham) and the sausage minces. The 20 μg/ gram Livestock animal origin products decreased by 1.3 log Colony Forming Unit / gram of Staphylococcus aureus and 1.5 log Colony Forming Unit / gram of the Escherichia coli in ground meat. It was also achieved that 160 μg/ gram of the Livestock animal origin products had the best inhibition and decreased in 3.9 log Colony Forming Unit / gram of the Staphylococcus aureus and 3.3 log Colony Forming Unit / gram of the Escherichia coli at 6 hours in the ground meats. In sausage mince, the Livestock animal origin products at concentrations of 160 μg/ gram could decrease by three log Colony Forming Unit /g of Staphylococcus aureus and 2.7 log Colony Forming Unit / gram of the Escherichia coli at 12 hours. After one day of the storage, no visible colonies of the Staphylococcus aureus or the Escherichia coli were detected in the sausage mince (203,204,205,206,207 and 208).

The Natural Preservatives from the Microorganism and Their Application for the Meat and its Products

The Lactic acid bacteria  strains secrete several bacterial growth inhibitory substances (the organic acids, the diacetyl, the phenyl lactate, the hydroxyphenyl lactate, the cyclic dipeptides, the hydroxy fatty acid, the propionate, and the hydrogen peroxide), the bacteriocins (the nisin, the acidophilin, the bulgaricin, the helveticin, the lactacin, the pediocin, the plantarim, the diplococcin, and the bifidocin), and the bacteriocin like inhibitory substances (the Bacteriocin Like Inhibitory Substance), which exhibit antibacterial activity and can control the spoilage and the foodborne pathogenic bacteria. The various bacteriocins, commercial bacteriocin preparations have been applied using nisin and pediocin. The Bacteriocins are peptides or proteins with antibacterial and antifungal effects that produce bacteria, mainly the lactic acid bacteria. The compounds are considered potential natural preservatives because of their inhibitory effects on the food spoilage or pathogenic bacteria. The Lactic acid bacteria bacteriocins vary in accordance with molecular size, the chemical structure, modifications during biosynthesis, presence of modified amino acid residues, and antimicrobial mechanisms. The Lactic acid bacteria bacteriocins can be categorized into two major classes: class I (the lanthionine containing antibiotics) with three subclasses (the Ia, Ib, and Ic) and the class II with four subclasses (IIa, IIb, IIc, and IId). The Class I bacteriocins generally include 19–50 amino acid residues (<5>30 kDa) and the thermally unstable peptides. The Class IV bacteriocins are large peptides complexed with the lipids or the carbohydrates. The bacterial cell surface exhibits a negative charge because the anionic characteristics of the cell membrane consist of the phosphatidylethanolamine, the phosphatidylglycerol, the lipopolysaccharide, the lipoteichoic acid, and the cardiolipin, and is generally captured by the positively charged bacteriocins. The cationic charged groups of the bacteriocins electrostatically interact with the anionic bacterial cell surface, while the hydrophobic surfaces are attached to the membrane and traverse the lipid bilayer. The bacteriocins self-associate or polymerize to develop complexes after passing through the lipid bilayer. The bacteriocins induce the cell death by increasing the permeability of the bacterial membrane, forming pores that cause dissipation of the proton motive force, exhaustion of ATP, and leakage of intracellular substrates. The Gram-positive bacteria origin bacteriocins only perform for the Gram-positive bacteria and are not effective against the Gram-negative bacteria because of their different membrane compositions and the selective membrane permeability. The disadvantages could be compensated by mixing processing with other preservatives and the application of further preservation methods (209,210,211,212 and 213).

The Nisin

The Nisin is the most representative class I bacteriocin. The Nisin is produced by several strains of the Lactococcus lactis, a species that is widely used for the dairy production. The Nisin was first approved as a food preservative in the United Kingdom in the 1950s and is now widely used worldwide and is permitted in over 50 countries. The structure of the nisin consists of a polypeptide with 34 amino acids, a 3.5 kDa molecular mass, and contains the methyllanthionine and the lanthionine groups. The Nisin has antimicrobial activities against a wide range of the Gram-positive bacteria, including the Staphylococcus spp., the Bacillus spp., the Listeria spp., and the Enterococcus spp. The Nisaplin is a typical commercial nisin formulation. The Nisin could provide long lasting bacteriostatic effects on the pathogenic bacteria in the beef jerky at room temperature. The shelf-life extensive effect of the nisin in the B. cereus inoculated with the beef jerky. The beef jerky without the nisin, the counts of the mesophilic bacteria and the B. cereus increasing is unlikely for the beef jerky treated with the nisin at 25 °C for 60 days. The B. cereus grew after three days in the 100 IU nisin/ gram. The treated groups and after 21 days in the 500 IU/ gram nisin treated groups. The nisin containing fermentate from the L. lactis 537 strain was evaluated for the inhibition of the Listeria monocytogenes in ready to eat sliced ham. The addition of the fermentate to the ready to eat sliced ham led to an immediate decrease in the Listeria monocytogenes counts from three log Colony Forming Unit / gram to below the detection limit stored at 4 °C (20 Colony Forming Unit / gram). The Nisin with the cinnamaldehyde and the grapefruit seed extract presented synergistic antibacterial effects. It reduced the counts of the Listeria monocytogenes by three log Colony Forming Unit / gram in the raw pork loin at 4 °C for 12 hours. The minimum inhibitory concentration of the nisin against the Listeria monocytogenes was 250 ppm in the laboratory media, but it was possible to reduce the concentration of 5–6 ppm against the growth of Listeria monocytogenes by mixing with the natural antibacterial substances in the pork (214,215,216,217,218 and 219).

The Pediocin

The Pediococcus spp., the Pediococcus acidilactici, and the Pediococcus pentosaceus are the main pediocin producing strains. Pediocin was classified into the bacteriocin group class IIa, characterized as small non modified peptides (<5>

The Sakacin

The Sakacins, a class II bacteriocin, are mainly produced by the Lactobacillus sakei or the Lactobacillus curvatus strains. The Commercial sakacin products are currently not presented. Compared to the nisin and the pediocin, the sakacins have a relatively narrow antimicrobial spectrum, especially with effective inhibition against the Listeria species. The antibacterial effect of the sakacin producing strain, the L. sakei CWBI B1365, and the L. curvatus CWBI B28, on the fate of the Listeria monocytogenes in the raw beef and poultry. In the refrigerated (5 °C) the raw beef, the L. sakei induced a decrease in the Listeria monocytogenes concentration by 1.5 log Colony Forming Unit / gram after seven days to two log Colony Forming Unit / gram after 14 days, and below the detection limit at 21 days. The addition of the L. curvatus reduced the Listeria monocytogenes to below the detection limit after seven days. However, in the poultry, the bacteriocin producing strain did not affect the inhibition of the Listeria monocytogenes. It was assumed that the type of the meat may have influenced the bacteriocin production by the Lactic acid bacteria. The antibacterial activity of different bacteriocin preparations using the sakacin Q produced by the L. curvatus ACU 1 on the meat surface was evaluated against the L. innocua . The freeze-dried reconstituted cell free supernatant (3200 AU/mL) was effective for the inhibition of L. innocua on the meat surface, decreasing its bacterial cell number to the detection limit (<2>

The Bacteriocin Like Inhibitory Substance 

The Bacteriocin Like Inhibitory Substance are among the antimicrobial substances produced by the bacteria and are not completely categorized in terms of amino acid composition, molecular size, and nucleotide sequence. Inside the ready to eat pork ham, the antibacterial effects of the Bacteriocin Like Inhibitory Substance produced by the Pediococcus pentosaceus American Type Culture Collection 43200 were assessed and compared with those of the commercially available nisin preparations (the Nisaplin). The Bacteriocin Like Inhibitory Substance showed effective antibacterial activity against the Listeria seeligeri by 0.74 log Colony Forming Unit / gram in the ready to eat ham stored at 4 °C after two days. The slight increase in the Listeria seeligeri counts was detected in the Bacteriocin Like Inhibitory Substance treated samples from six days to the end of the storage. The Nisaplin did not present any antibacterial effect for up to two days. After two days, the Nisaplin started to induce a decrease in the Listeria seeligeri counts throughout the refrigerated storage. This might have been due to the higher sensitivity of the Bacteriocin Like Inhibitory Substance to residual proteases compared to the nisin, thus weakening its antibacterial effect. The Bacteriocin Like Inhibitory Substance producing the Lactic acid bacteria strains, the P. acidilactici KTU05 7, the Pediococcus pentosaceus KTU05 9, and the Listeria sakei KTU05 6, were used to ferment the plant (the Jerusalem artichoke, the Helianthus tuberosus L.), and 5% of the fermented products were tested to inhibit the foodborne pathogen at 18 °C for half day in the ready to cook minced pork. The P. acidilactici fermented product presented the highest antimicrobial activity compared to the other strains. The counts of the Escherichia coli, the Enterococcus faecalis, the Staphylococcus aureus, and the Streptococcus spp. were reduced by 5.53, 4.37, 4.86, and 3.84 log Colony Forming Unit / gram, respectively, compared to the control groups, suggesting that the fermented product of the Bacteriocin Like Inhibitory Substance producing strains showed an enhanced antibacterial effect. The Bacteriocin Like Inhibitory Substance obtained from the Enterococcus faecium DB1 inhibited the growth and formation of the biofilms of the Clostridium perfringens in the chicken meat. The 2.5 mg/mL of DB1 Bacteriocin Like Inhibitory Substance suppressed the growth of the Clostridium perfringens by 30%. The Clostridium perfringens growth was inhibited by 50% at 5 mg/mL The DB1 Bacteriocin Like Inhibitory Substance. The Biofilm formation by the Clostridium perfringens treated with 5 mg/mL DB1 Bacteriocin Like Inhibitory Substance was radically reduced by 90% at 4 °C for three days compared to the control groups. The 2.5 mg/mL of the DB1 Bacteriocin Like Inhibitory Substance also inhibited biofilm formation by the Clostridium perfringens under the same conditions. The Bacteriocin Like Inhibitory Substance could inhibit the formation of the Clostridium perfringens biofilms on the chicken surfaces due to its antibacterial effect (232,233,234,235,236 and 237).

The Other Microorganism Sources

The mytichitin CB peptide, which was isolated from the blood lymphocytes of the Mytilus coruscus, showed antibacterial effects against the Gram-positive bacteria and the fungi. The mytichitin CB peptide expressed by Pichia pastorisi and applied it to the pork preservation. The total viable counts of the treated group with 6 mg/L of mytichitin CB derived from the P. pastorisi was reduced by 33% (1–2 log Colony Forming Unit / gram) compared to the control group after the storage at 4 °C for 5 days. The Mytichitin CB effectively inhibited the total bacterial growth during the storage compared to the groups treated with 50 mg/L of the nisin. The Mytichitin CB at 6 and 12 mg/L suppressed Staphylococcus spp. and Escherichia spp., respectively, with a reduction of 1–2 log Colony Forming Unit / gram, respectively. The Listeria spp. and the Pseudomonas spp. we’re not detected during the storage, unlike the control and nisin treated groups. The Hispidalin is a unique Antimicrobial Peptides derived from the seeds of the Benincasa hispida and has been shown to exhibit the antimicrobial effects against the various bacteria. The hispidalin expressed by the P. pastorisi was used as a preservative for the pork. The Pork treated with 100 μg/mL hispidalin showed bacteriostatic effects during the entire refrigerated storage period. The total viable count of the pork with 100 μg/mL hispidalin was one log Colony Forming Unit /gram decrease than that of the control group at 4 °C for seven days (236,237, 238,239 and 240).

Conclusions

The Meat and its products are excellent nutrient sources due to their abundant protein content, the essential amino acids, the vitamins, and the minerals. The meat and its products are susceptible to the contamination by the foodborne pathogenic and the various spoilage bacteria because of their high-water activity and the nutrient content. The application of the preservatives is an indispensable element in the livestock food processing to prevent the food poisoning, delay the spoilage, and extend their shelf life. The Industrial preservatives, commonly made up of the chemicals, are not demanded by the food customers because of their negative health concerns. The natural preservatives derived from the plants (the rosemary, the sage, the chestnut, the Grapefruit Seed Extract, and the tumeric), the animals (the lysozyme, the lactoferrin, the lactoferoxidase, the ovotransferrin, and others), and the bacteria (the organic acids, the bacteriocins, and the Bacteriocin Like Inhibitory Substance) have been explored as alternatives to the chemical preservatives. The versatility of the natural preservatives compared to the chemical preservatives is limited due to the production cost, the standardization, the insufficient toxicity studies, and the negative sensory effects on the food. To compensate for these disadvantages, various applications have been studied for their synergistic effect with the other natural preservatives with reduced the application concentrations compared to single use, the application of the physical treatment (the gamma irradation, the high-pressure processing, and the drying), the encapsulation, and the possibility of the packaging materials. The various natural preservatives and the application methods to inhibit the growth of the foodborne pathogenic and the spoilage bacteria in the livestock foods. The Natural preservatives are expected to be in high demand due to the consumer and the industrial requests. Therefore, it is necessary to explore various applications of the existing natural preservatives, while continuously searching for the novel ones.

Conflicts of Interest

The author declares no conflicts of interest