Natural Phenolic Compounds for the Control of Oxidation, Bacterial Spoilage, and Foodborne Pathogens in Meat

Control of Listeria monocytogenes on Frankfurters by Surface Treatment with Olive Mill Wastewater Polyphenolic Extract

Listeria monocytogenes (LM) is a frequent post-process contaminant in meat products. This study aimed to investigate the antilisterial effectiveness of post-process antimicrobial treatments employing olive mill wastewater polyphenolic extract (PE) in commercially manufactured frankfurters. Frankfurters were inoculated on the surface with a three-strain LM mixture (~102 CFU/g), treated on the surface with PE in a 2-fold series of concentrations (PM, 2PM, 4PM) and a control group (CTR) of PE-untreated samples. Then, the frankfurters were vacuum-packed and stored at 4 °C for 28 days. Samples were examined on days 0, 7, 14, 21, and 28 for LM count, in silico growth modeling, and impacts on pH, water activity (aw), and sensory characteristics. From T(time) 7, the PE treatment showed a significant effect on LM growth, registering maximum Δ values between CTR and 4PM of 3.19, 4.86, 4.59, 4.39 at T7, T14, T21, T28, respectively. Minimum effect was attributable to PM treatment with Δ values (CTR versus PM) of 2.07, 2.52, 1.14, 0.65 at T7, T14, T21, T28, respectively. No significant changes occurred in pH (average 6 at T0 and 5.9 at T28), aw (average 0.978 at T0 and 0.968 at T28), nor in sensory profile (p > 0.05). These findings suggest that PE is an effective natural antimicrobial, offering a promising approach to enhancing food safety and extending shelf life in meat products.

The Antimicrobial Effect of Thymol and Carvacrol in Combination with Organic Acids Against Foodborne Pathogens in Chicken and Beef Meat Fillets

Bioactive compounds and organic acids are applied to a wide range of foods against different types of foodborne pathogens. In the present study, carvacrol and thymol (1000 mg/L) were applied in wine-based marinades, alone or in combination with them and in combination with tartaric acid, malic acid, ascorbic acid, citric acid, and acetic acid (in concentration 0.1% w/v), in chicken and beef fillets and their antimicrobial activity, antioxidant capacity, and pH were estimated during refrigerated storage. Likewise, their antimicrobial activity was recorded against Enterobacteriaceae, total mesophilic bacteria, yeasts/molds, and lactic acid bacteria. The outcome demonstrated that both meats kept under similar storage conditions (4 °C/9 days) exhibited lower microbial growth, particularly with Enterobacteriaceae, when treated with wine-based carvacrol-thymol marinades and may extend their shelf-life. This antimicrobial action was more pronounced in the beef samples. The total phenolic content (TPC) and the antioxidant activity of the applied marinades were determined using the Folin-Ciocalteau method and ABTS and DPPH radical scavenging activity methods, respectively. The results revealed that marinades with thymol and/or carvacrol in combination with acetic or ascorbic acid had greater TPC and antioxidant activity. The pH values of the respective marinades applied to both chicken and beef fillets exhibited an upturn during storage. Consequently, these marinades, even at low concentrations, could be used as natural preservatives in meat products.

Phenolic Compounds and Bacteriocins: Mechanisms, Interactions, and Applications in Food Preservation and Safety

Beneficial properties of different natural antimicrobials are topics of scientific curiosity for improving safety and extending the shelf life of food commodities. In this regard, phenolic compounds, natural molecules known for their antioxidant, anti-inflammatory, and antimicrobial properties can be right choice. Moreover, bacteriocins, antimicrobial peptides produced by various microorganisms, capable of inhibiting the growth of other bacteria, particularly closely related species can be genuine alternative. Combining phenolic compounds with bacteriocins can enhance antimicrobial effects, extending the shelf-life of food products by combating spoilage and foodborne pathogens. Despite their potential, the chemical interactions between phenolic compounds and bacteriocins, including synergistic and antagonistic effects, are not well understood. Key areas needing further research include the following: the mechanisms of action against different bacterium types, interactions with cell membranes, enzyme activity, and gene expression; the effects of environmental factors like concentration, pH, temperature, and food matrix specificity on their interactions; and methods for incorporating these compounds into food products and packaging materials to improve food safety. Additionally, the safety, toxicity, allergenicity, sensory properties, nutritional value, regulatory approval, and consumer acceptance of using phenolic compounds and bacteriocins in food products require thorough investigation.

Thyme Essential Oil as a Potential Tool Against Common and Re-Emerging Foodborne Pathogens: Biocidal Effect on Bacterial Membrane Permeability

Over the past decade, foodborne diseases have become a significant public health concern, affecting millions of people globally. Major pathogens like Salmonella spp., Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus contaminate food and cause several infections. This study investigates the potential of thyme essential oil (Thy-EO) as a natural antimicrobial agent against most common and re-emerging foodborne bacteria, including S. enterica, Yersinia enterocolitica, and L. monocytogenes. Preliminary tests provided qualitative evidence of Thy-EO's efficacy by evaluating its antibacterial activity through direct contact and vapor phase exposure. Then, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were defined to quantitatively evaluate the bacteriostatic and bactericidal effects of Thy-EO, revealing a strong inhibitory effect against S. enterica, Y. enterocolitica and L. monocytogenes. Additionally, Thy-EO exerted rapid bactericidal kinetics characterized by the disruption of bacterial cell membrane integrity over time. Results highlight Thy-EO's potential as an alternative antimicrobial agent, demonstrating that treatment with Thy-EO significantly and irreversibly affects the growth of the tested foodborne pathogens.

Antimicrobial Properties of Fennel By-Product Extracts and Their Potential Applications in Meat Products

Background: Beef burgers are perishable meat products, and to extend their shelf life, EU Regulation 1129/11 permits the use of certain additives. Objectives: However, given the concerns of health-conscious consumers and the potential toxicity of synthetic substances, this study aimed to explore the use of fennel waste extracts as natural preservatives. Methods: This study characterized the bioactive compounds (phenolic content), the antioxidant activity (ABTS+ and DPPH assay), and the antimicrobial properties (against Salmonella enterica serotype Enteritidis, Escherichia coli, Staphylococcus aureus, Bacillus cereusi, and Pseudomonas aeruginosa) of different fennel waste extracts (LF, liquid fraction; SF, solid fraction and PF, pellet fraction). Additionally, the potential use of the best fennel extract was evaluated for its impact on beef burger shelf life (up to 18 days at 4 ± 1 °C) in terms of microbiological profile, pH, and activity water (aw). Results: The PF extract, which was rich in flavones, hydroxybenzoic, and hydroxycinnamic acids, demonstrated the highest antioxidant and antimicrobial activities. Microbiological analyses on beef burgers with PF identified this extract as a potential antimicrobial substance. The aw and pH values did not appear to be affected. Conclusions: In conclusion, fennel extracts could be proposed as natural compounds exploitable in beef burgers to preserve their quality and extend their shelf-life.

The Impact of Chlorella vulgaris Fortification on the Nutritional Composition and Quality Characteristics of Beef Burgers

Chlorella vulgaris (C.V) is known for its high protein and nutrient contents and has been touted as a potential functional ingredient in food products. For this study, beef burgers were formulated with varying levels of Chlorella vulgaris fortification (0%, 0.5%, 1%, and 1.5% by weight). The nutritional composition, including proximate analysis and mineral content, was determined for each treatment group. The quality characteristics evaluated included thiobarbituric acid (TBA), total volatile base nitrogen (TVBN), pH, and total acidity. The study included extracting the active substances from Chlorella vulgaris using three solvents, 50% ethanol, 95% ethanol, and water, to evaluate the effect on the antimicrobial and antioxidant activity. The results showed that the water extract had the highest total phenolic content (183.5 mg gallic acid equivalent per gram) and the highest flavonoid content (54 mg quercetin per gram). The aqueous extract had the highest content of total antioxidants, followed by the 95% ethanol and 50% ethanol extracts. Meanwhile, the 50% ethanol extract showed the best antimicrobial activity, while the aqueous extract had less of an effect on Gram-positive bacteria and no effect on E. coli. For the burger treatments, at the end of the storage period, it was observed that the microbial load of the treatments decreased compared to the control, and there was a high stability in the total volatile base nitrogen (TVBN) values for the treatments compared to the control, reaching a value of 22.4 at month 5, which is well above the acceptable limit, indicating spoilage. The pH values were higher for all of the treatments, with a lower total acidity for all of the treatments compared to the control. In conclusion, utilizing Chlorella vulgaris algae as a natural preservative to extend the freshness of burgers is a sustainable and innovative approach to food preservation. By harnessing the power of this green superfood, we not only enhance the shelf life of our food products but also contribute to a healthier and more environmentally friendly food industry.

Valorisation of raw mango pickle industry waste into antimicrobial agent against postharvest fungal pathogens

In mango pickle industry, a significant quantity of mango seed kernels is discarded as solid wastes. These seed kernels can be an ideal source for obtaining extracts rich in bioactive polyphenolic compounds with good antioxidant properties. The potential of mango kernel phenolic extract (MKPE) was investigated as a natural and effective antimicrobial agent for controlling major postharvest fungal pathogen infections, a significant threat to global food supply chains. Fungal pathogens contribute to the deterioration of fruits, vegetables, and grains during storage and transportation, leading to economic losses and compromised food safety. MKPE was obtained from pickling variety 'Ramkela' raw mango kernels, and its phenolic composition was characterized using LC-MS. The in vitro antifungal activity of MKPE against Botrytis cinerea, Colletotrichum gloeosporoides, and Rhizopus stolonifer was evaluated in vitro. A concentration-dependent inhibition of fungal radial growth against all three pathogens was observed, exhibiting the potential of MKPE as a valuable natural resource for addressing postharvest losses caused by fungal pathogens. The extraction process yielded a total phenolic content of 2128 mg GAE/100 g. Major polyphenolic bioactive compounds present were mangiferin, quercetin, and rhamnetin. The in-vitro antimicrobial assay showed reduction in the radial growth and inhibition percent of the pathogens. EC50 values of MKPE for B. cineria, C. gloeosporoides, and R. stolonifer was found to 364.17, 963.8 and 926 ppm, respectively. Our results demonstrate an economical, sustainable, and eco-friendly approach to manage post-harvest diseases rendered by fungi using mango MKPE from pickling industry waste.

Exploring Propolis as a Sustainable Bio-Preservative Agent to Control Foodborne Pathogens in Vacuum-Packed Cooked Ham

The search for natural food additives makes propolis an exciting alternative due to its known antimicrobial activity. This work aims to investigate propolis' behavior as a nitrite substitute ingredient in cooked ham (a ready-to-eat product) when confronted with pathogenic microorganisms of food interest. The microbial evolution of Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, and Clostridium sporogenes inoculated at known doses was examined in different batches of cooked ham. The design of a challenge test according to their shelf life (45 days), pH values, and water activity allowed the determination of the mesophilic aerobic flora, psychotropic, and acid lactic bacteria viability. The test was completed with an organoleptic analysis of the samples, considering possible alterations in color and texture. The cooked ham formulation containing propolis instead of nitrites limited the potential growth (δ < 0.5 log10) of all the inoculated microorganisms until day 45, except for L. monocytogenes, which in turn exhibited a bacteriostatic effect between day 7 and 30 of the storage time. The sensory analysis revealed the consumer's acceptance of cooked ham batches including propolis as a natural additive. These findings suggest the functionality of propolis as a promising alternative to artificial preservatives for ensuring food safety and reducing the proliferation risk of foodborne pathogens in ready-to-eat products.

Preventing Microbial Growth in Game Meat by Applying Polyphenolic Extracts from Olive Mill Vegetation Water

We studied the efficacy of different formulations of polyphenol extracts (mainly containing hydroxytyrosol and tyrosol) from olive mill vegetation water on the microflora on the surfaces of game meat cuts with high or low initial bacterial loads. Meat with a high microbial load (>5 Log cfu/g; mean value = 6.83 ± 0.45 standard deviation) was immersed for 10 or 60 sec into 25% and 10% solutions of microencapsulated freeze-dried and non-encapsulated polyphenolic extracts. Aerobic colony, Enterobacteriaceae, Pseudomonas spp., and lactic acid bacteria counts were determined on treated samples compared to controls after 7 days of storage (in vacuum-packed conditions at +3 °C). Significant differences were registered only for aerobic colony count for a 10% liquid extract treatment (0.64 log reduction). In contrast, the dipping or immersion of game meat with low initial microbial loads (<5 Log cfu/g; mean value = 3.58 ± 0.72 standard deviation) in 10% solutions of the polyphenol extracts effectuated significant reductions in all bacteria counts (p < 0.002) at 7 and 14 days of storage for different extracts, independently from the application methods. The use of the extracts to inhibit bacterial growth in game meat should only be considered if a good hygienic baseline is guaranteed.

Antioxidant activity of an Mg(II) compound containing ferulic acid as a chelator: potential application for active packaging and riboflavin stabilisation

Foods rich in riboflavin (Rf) are susceptible to degradation due to oxidative processes with the formation of radicals. Herein, we describe the features and stability of an Mg(II) complex containing ferulic acid (fer) and 1,10-phenanthroline (phen) as chelators: henceforth called Mg(phen)(fer). The electrochemical behavior of Mg(phen)(fer) is pH dependent and results from the stabilisation of the corresponding phenoxyl radical via complexation with Mg(II). This stabilisation enhances the antioxidant activity of Mg(phen)(fer) with respect to free fer and commercial antioxidants. Mg(phen)(fer) scavenges and neutralizes DPPH˙ (IC50 = 15.6 μmol L-1), ABTS˙+ (IC50 = 5.65 μmol L-1), peroxyl radical (IC50 = 5.64 μg L-1) and 1O2 (IC50 = 0.7 μg m-1). Mg(phen)(fer) effectively protects riboflavin (Rf) against photodegradation by quenching the singlet excited states of Rf regardless of the conditions. Also, the complex Mg(phen)(fer) was effectively incorporated into starch films, broadening its applications, as shown by microbiological studies. Thus, Mg(phen)(fer) has high potential for use in Rf-rich foods and to become a new alternative to the synthetic antioxidants currently used.

In Vitro and In Silico Antioxidant Activity and Molecular Characterization of Bauhinia ungulata L. Essential Oil

Bauhinia ungulata is an antioxidant medicinal plant that has been manipuled in Brazil to lower glycemic index as well is for alternative treatment for diabetes. Therefore, the present hearch has aimed to investigates the antioxidant effects of the essential oil of Bauhinia ungulata L. (EOBU) collected in Amazon region better specified in Boa Vista, Roraima, Brazil, located in the Amazon region. Gas chromatography had been used to characterize the components, and antioxidant assays such as DPPH, TAC, reducing power, Fe2+ chelation, and total phenols had also been performed. The major constituents had molecularly anchored with the human catalase (CAT) enzyme, and maltol has showed as a positive control. Among the 25 revealed components, the main ones have been α-bisabolol (27.2 %), β-Caryophyllene (12.5 %) and Epi-γ-eudesmol (13.6 %). The EOBU has comproved a TAC value of 618.79 mg of ascorbic acid equivalent, free radical scavenging capacity (DPPH) around 53.7 % and 65.27 %, Fe2+ chelation capacity of 161±6 and 126.7±39.6, for 0.1 mg.mL-1 and 0.5 mg.mL-1 , respectively. The power around the EOBU has appeared percentages equals to 28.66 %, 44.6 %, and 77.03 % in the concentrations tested. As well as, 96.5 % of total phenols. The compounds α-bisabolol (-5.7±0.4 Kcal.mol-1 ) and β-caryophyllene (-6.1±0.5 Kcal.mol-1 ) have showed good interaction with CAT compared to Maltol (-4.4±0.4 Kcal.mol-1 ). The present work has demonstrated that EOBU functions as a potent antioxidant, capable of scavenging free radicals and reducing oxidative stress damage.

Application of White-Wine-Pomace-Derived Ingredients in Extending Storage Stability of Fresh Pork Burgers

White wine pomace, a by-product from winemaking, was stabilized after the application of thermal blanching (with the aim of deactivating the polyphenoloxidase enzyme), milling, and processing by hydrostatic high-pressure treatment (with the aim of reducing initial microbial loads while preserving phenolic compounds content). The valorized pomace (VP) ingredient was added at different proportions to pork burgers (0.5%, 1%, and 3% w/w) to improve their preservation, and the effect was compared to those produced by sulfites and with a control (without sulfites or VP). Burgers were vacuum-packed and refrigerated for 7 days. Microbiological, color, oxidation, and sensory parameters were analyzed. Neither sulfites nor VP reduced the microbial development of most microorganism groups evaluated (p > 0.05); however, both prevented coliform growth during storage (p < 0.01). The use of sulfites prevented the discoloration of burgers during storage, while VP had no effect (p < 0.001). On the contrary, VP limited lipid and protein oxidation development during storage (p > 0.05), while sulfites had no effect. Therefore, the use of VP from white wine production could have an antioxidant effect but a limited antimicrobial or color-protective effect for the preservation of pork burgers.

A Guideline for Assessment and Characterization of Bacterial Biofilm Formation in the Presence of Inhibitory Compounds

Campylobacter jejuni, a zoonotic foodborne pathogen, is the worldwide leading cause of acute human bacterial gastroenteritis. Biofilms are a significant reservoir for survival and transmission of this pathogen, contributing to its overall antimicrobial resistance. Natural compounds such as essential oils, phytochemicals, polyphenolic extracts, and D-amino acids have been shown to have the potential to control biofilms formed by bacteria, including Campylobacter spp. This work presents a proposed guideline for assessing and characterizing bacterial biofilm formation in the presence of naturally occurring inhibitory molecules using C. jejuni as a model. The following protocols describe: i) biofilm formation inhibition assay, designed to assess the ability of naturally occurring molecules to inhibit the formation of biofilms; ii) biofilm dispersal assay, to assess the ability of naturally occurring inhibitory molecules to eradicate established biofilms; iii) confocal laser scanning microscopy (CLSM), to evaluate bacterial viability in biofilms after treatment with naturally occurring inhibitory molecules and to study the structured appearance (or architecture) of biofilm before and after treatment.

Phytochemicals and bioactive constituents in food packaging - A systematic review

Designing and manufacturing functional bioactive ingredients and pharmaceuticals have grown worldwide. Consumers demand for safe ingredients and concerns over harmful synthetic additives have prompted food manufacturers to seek safer and sustainable alternative solutions. In recent years the preference by consumers to natural bioactive agents over synthetic compounds increased exponentially, and consequently, naturally derived phytochemicals and bioactive compounds, with antimicrobial and antioxidant properties, becoming essential in food packaging field. In response to societal needs, packaging needs to be developed based on sustainable manufacturing practices, marketing strategies, consumer behaviour, environmental concerns, and the emergence of new technologies, particularly bio- and nanotechnology. This critical systematic review assessed the role of antioxidant and antimicrobial compounds from natural resources in food packaging and consumer behaviour patterns in relation to phytochemical and biologically active substances used in the development of food packaging. The use of phytochemicals and bioactive compounds inside packaging materials used in food industry could generate unpleasant odours derived from the diffusion of the most volatile compounds from the packaging material to the food and food environment. These consumer concerns must be addressed to understand minimum concentrations that will not affect consumer sensory and aroma negative perceptions. The research articles were carefully chosen and selected by following the Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines.

A review on plasma-activated water and its application in the meat industry

Meat is a nutritious food with a short shelf life, making it challenging to ensure safety, quality, and nutritional value. Foodborne pathogens and oxidation are the main concerns that lead to health risks and economic losses. Conventional approaches like hot water, steam pasteurization, and chemical washes for meat decontamination improve safety but cause nutritional and quality issues. Plasma-activated water (PAW) is a potential alternative to thermal treatment that can reduce oxidation and microbial growth, an essential factor in ensuring safety, quality, and nutritional value. This review explores the different types of PAW and their physiochemical properties. It also outlines the reaction pathways involved in the generation of short-lived and long-lived reactive nitrogen and oxygen species (RONS) in PAW, which contribute to its antimicrobial abilities. The review also highlights current studies on PAW inactivation against various planktonic bacteria, as well as critical processing parameters that can improve PAW inactivation efficacy. Promising applications of PAW for meat curing, thawing, and decontamination are discussed, with emphasis on the need to understand how RONS in PAW affect meat quality. Recent reports on combining PAW with ultrasound, mild heating, and non-thermal plasma to improve inactivation efficacy are also presented. Finally, the need to develop energy-efficient systems for the production and scalability of PAW is discussed for its use as a potential meat disinfectant without compromising meat quality.

The pro-oxidant action of high-oxygen MAP on beef patties can be counterbalanced by antioxidant compounds from common hawthorn and rose hips

The objective of this research was to evaluate the effectiveness of antioxidant-rich extracts from rose hip (Rosa canina L.; RC) and hawthorn (Crataegus monogyna Jacq.; CM) at minimizing the oxidative damage to proteins and lipids in beef patties subjected to a high‑oxygen (HiOx-MAP) and vacuum (Vacuum) packaging atmosphere. The extracts of RC and CM were characterized by quantifying bioactive compounds, namely, phenolic compounds, tocopherols and vitamin C. Both fruits had high concentrations of bioactive compounds, with RC having the highest total phenolic and vitamin C content. Yet, CM was the most efficient in protecting beef patties against protein carbonylation, reducing, as a result, the instrumental toughness in cooked beef patties. The use of CM and RC extracts in beef patties significantly improved consumer purchase intention in HiOx-MAP packaging systems. The use of CM and RC extracts or their combination in future research would be an effective antioxidant means to decrease the pro-oxidative effects caused by HiOx-MAP in red meat.

Investigation of Chemical Constituents and Antioxidant Activity of Biologically Active Plant-Derived Natural Products

The aim of this publication is to present rapid screening methods (visual/colorimetric) that will enable quick identification of the presence of biologically active compounds in aqueous solutions. For this reason, 26 plant extracts obtained by ultrasound-assisted extraction were analysed for the content of these compounds. Higher plants, used as a raw material for extraction, are common in Europe and are easily available. The article proposes a comparison of various protocols for the identification of various compounds, e.g., phenolic compounds (phenols, tannins, anthocyanins, coumarins, flavones, flavonoids), vitamin C, quinones, quinines, resins, glycosides, sugars. Initial characterisation of the composition of plant extracts using fast and inexpensive methods allows you to avoid the use of time-consuming analyses with the use of advanced research equipment. In addition, the antioxidant activity of plant extracts using spectrophotometric methods (DPPH, ABTS, FRAP assay) and quantitative analysis of plant hormones such as abscisic acid, benzoic acid, gibberellic acid, indole acetic acid, jasmonic acid, salicylic acid, zeatin, zeatin riboside, and isipentenyl adenine was performed. The obtained results prove that the applied visual methods show different sensitivity in detecting the sought chemical compounds. Therefore, it is necessary to confirm the presence or absence of bioactive substances and their concentration using modern analytical methods.

Plant Antimicrobials for Food Quality and Safety: Recent Views and Future Challenges

The increasing demand for natural, safe, and sustainable food preservation methods drove research towards the use of plant antimicrobials as an alternative to synthetic preservatives. This review article comprehensively discussed the potential applications of plant extracts, essential oils, and their compounds as antimicrobial agents in the food industry. The antimicrobial properties of several plant-derived substances against foodborne pathogens and spoilage microorganisms, along with their modes of action, factors affecting their efficacy, and potential negative sensory impacts, were presented. The review highlighted the synergistic or additive effects displayed by combinations of plant antimicrobials, as well as the successful integration of plant extracts with food technologies ensuring an improved hurdle effect, which can enhance food safety and shelf life. The review likewise emphasized the need for further research in fields such as mode of action, optimized formulations, sensory properties, safety assessment, regulatory aspects, eco-friendly production methods, and consumer education. By addressing these gaps, plant antimicrobials can pave the way for more effective, safe, and sustainable food preservation strategies in the future.

Phenolic Compounds in Bacterial Inactivation: A Perspective from Brazil

Phenolic compounds are natural substances that are produced through the secondary metabolism of plants, fungi, and bacteria, in addition to being produced by chemical synthesis. These compounds have anti-inflammatory, antioxidant, and antimicrobial properties, among others. In this way, Brazil represents one of the most promising countries regarding phenolic compounds since it has a heterogeneous flora, with the presence of six distinct biomes (Cerrado, Amazon, Atlantic Forest, Caatinga, Pantanal, and Pampa). Recently, several studies have pointed to an era of antimicrobial resistance due to the unrestricted and large-scale use of antibiotics, which led to the emergence of some survival mechanisms of bacteria to these compounds. Therefore, the use of natural substances with antimicrobial action can help combat these resistant pathogens and represent a natural alternative that may be useful in animal nutrition for direct application in food and can be used in human nutrition to promote health. Therefore, this study aimed to (i) evaluate the phenolic compounds with antimicrobial properties isolated from plants present in Brazil, (ii) discuss the compounds across different classes (flavonoids, xanthones, coumarins, phenolic acids, and others), and (iii) address the structure-activity relationship of phenolic compounds that lead to antimicrobial action.

Effects of Plant-Based Antioxidants in Animal Diets and Meat Products: A Review

The perceived level of risk associated with a food product can influence purchase and consumption decisions. Thus, current trends in food safety address an issue of general interest-the identification of healthy and economical alternatives to synthetic antioxidants that may have harmful effects on human health. Still, the processors' target is to increase the shelf life of food products using preserving substances. Natural antioxidants can be extracted and used in the food industry from different plants, such as blueberry, broccoli, chokeberry, cinnamon, ginger, olives, oregano, etc. The identification of the main natural antioxidant types that have been used in the food industry is very important in order to provide a comprehensive analysis of the researched topic. In this regard, the aim of this paper was to illustrate the positive aspects of using natural antioxidants with preservative roles in meat products, while, at the same time, highlighting the potential risks induced by these compounds. All of those aspects are correlated with the impact of sensorial attributes and the improvement of the nutritional value of meat products.

Antibacterial and Antibiofilm Efficacy of Thyme (Thymus vulgaris L.) Essential Oil against Foodborne Illness Pathogens, Salmonella enterica subsp. enterica Serovar Typhimurium and Bacillus cereus

Nowadays, the wide spread of foodborne illness and the growing concerns about the use of synthetic food additives have shifted the focus of researchers towards essential oils (EOs) as possible antimicrobials and preservatives of natural origin. Thanks to their antimicrobial properties against pathogenic and food spoilage microorganisms, EOs have shown good potential for use as alternative food additives, also to counteract biofilm-forming bacterial strains, the spread of which is considered to be among the main causes of the increase in foodborne illness outbreaks. In this context, the aim of this study has been to define the antibacterial and antibiofilm profile of thyme (Thymus vulgaris L.) essential oil (TEO) against widespread foodborne pathogens, Salmonella enterica subsp. enterica serovar Typhimurium and Bacillus cereus. TEO chemical composition was analyzed through gas chromatography-mass spectrometry (GC-MS). Preliminary in vitro antibacterial tests allowed to qualitatively verify TEO efficacy against the tested foodborne pathogens. The subsequent determination of minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values allowed to quantitatively define the bacteriostatic and bactericidal effects of TEO. To evaluate the ability of essential oils to inhibit biofilm formation, a microplate assay was performed for the bacterial biofilm biomass measurement. Results suggest that TEO, rich in bioactive compounds, is able to inhibit the growth of tested foodborne bacteria. In addition, the highlighted in vitro anti-biofilm properties of TEO suggest the use of this natural agent as a promising food preservative to counteract biofilm-related infections in the food industry.

Characterization of Chia Seeds, Cold-Pressed Oil, and Defatted Cake: An Ancient Grain for Modern Food Production

The increasing demand for superfoods has resulted in an increase in chia seeds consumption. The reintroduction of this ancient crop in agriculture is useful to ensure food security since it can grow in high-stress conditions. The current study aimed to characterize chia seeds, cold-pressed oil, and defatted cake (the oil extraction by-product) to improve their value and to meet consumer's expectations (low-fat products). Chia seeds presented a significantly higher energy value than cake (444 vs. 284 kcal/100 g, respectively) due to fat removal (33 vs. 7%). The cake showed higher contents of total minerals (6 vs. 5%), protein (27 vs. 18%), and fiber (48 vs. 38%) in comparison to the seeds, and was hence considered a promising food ingredient. The major fatty acid in oil, seeds, and cake was α-linolenic acid (62-66%), and the vitamin E content was 409, 200, and 44 mg/kg, respectively. The major amino acid in the seeds and cake was glutamic acid (49 vs. 36 mg/g). The oil had a low oxidative stability (1 h), and the total phenolics content was 1.3 mg gallic acid equivalents/100 g. Chia cake incorporation in food formulations will follow consumer's interests, and the obtained oil can be used to improve the oil supply for different applications. This approach adds value to the concept of "one health" since it includes the culture, the environment, and the consumers.

Bifidobacterium animalis A12, a Probiotic Strain That Promotes Glucose and Lipid Metabolism, Improved the Texture and Aroma of the Fermented Sausage

Bifidobacterium animalis A12 was used for the development of fermented sausage. The growth activity, tolerance, and enzyme activity of B. animalis A12 and its contribution to the texture and flavour of fermented sausages were evaluated. Additionally, the sensory texture, flavour components, and amino acid nutrients during the fermentation process were assessed. B. animalis had high tolerance to NaCl and nitrite, and B. animalis A12 had protease and lipase activities. The pH value of sausage fermented with B. animalis A12 was lower than that of sausage fermented without any fermentation strain. Hexanal, heptanal, decanal, cis-2-decanal, and 4-methoxy-benzaldehyde are the unique aldehydes flavour components of fermented sausages in the A12 group. The highest content of volatile flavour substances and amino acids, and the color and texture characteristics of fermented sausage in the experimental group at 18 h were better than those at other times. These results suggest that B. animalis A12 has the potential to be used as a starter culture for im-proving flavour and texture in fermented sausage.

Determination of phenolic compounds and their antioxidant activity of Iranian Allium sativum controversum extracts and their antimicrobial properties in fresh sausages

In this study, Iranian Allium sativum controversum extracts, as a valuable source of bioactive compounds such as antioxidants, extracted by solvents were analyzed. Based on the analysis of total phenolic content (TPC) and total flavonoid content (TFC) and radical scavenging activity (1,1-diphenyl-2-picrylhydrazyl (DPPH)) of each extract, ethanol extracts were finally added to the sausage formulation at 0.5 and 1.5%w/v. Treatments were kept at refrigerated temperature (4-5°C) for 1, 15, and 30 days, and DPPH and microbial assays were performed on the treatments and the control samples. Experimental data were performed in a completely randomized design with the factorial arrangement. Hydroalcoholic extract had the highest total phenols and the aqueous extract of Allium sativum controversum showed the highest radical scavenging activity (11.85 ± 0.81 mg/g). No colony counts were observed on the first day of the coliform count. On 15 to 30 days, the control sample showed the highest count and the treatment containing Allium sativum controversum extract (1.5%) had the lowest coliform count. During the first month, the control sample had the highest count of Staphylococcus aureus. Regarding mold and yeast, a treatment containing Allium sativum controversum extract (1.5%) and the control sample had the lowest and highest count, respectively. The results showed that using Allium sativum controversum extracts and increased radical scavenging activity reduced microbial growth during the storage period.

The role of ion-lipid interactions and lipid packing in transient defects caused by phenolic compounds

The transient disruption of membranes for the passive permeation of ions or small molecules is a complex process relevant to understanding physiological processes and biotechnology applications. Phenolic compounds are widely studied for their antioxidant and antimicrobial properties, and some of these activities are based on the interactions of the phenolic compound with membranes. Ions are ubiquitous in cells and are known to alter the structure of phospholipid bilayers. Yet, ion-lipid interactions are usually ignored when studying the membrane-altering properties of phenolic compounds. This study aims to assess the role of Ca2+ ions on the membrane-disrupting activity of two phenolic acids and to highlight the role of local changes in lipid packing in forming transient defects or pores. Results from tethered bilayer lipid membrane electrical impedance spectroscopy experiments showed that Ca2+ significantly reduces membrane disruption by caffeic acid methyl ester and caffeic acid. As phenolic acids are known metal chelators, we used UV-vis and fluorescence spectroscopy to exclude the possibility that Ca2+ interferes with membrane disruption by binding to the phenolic compound and subsequently preventing membrane binding. Molecular dynamics simulations showed that Ca2+ but not caffeic acid methyl ester or caffeic acid increases lipid packing in POPC bilayers. The combined data confirm that Ca2+ reduces the membrane-disrupting activity of the phenolic compounds, and that Ca2+-induced changes to lipid packing govern this effect. We discuss our data in the context of ion-induced pores and transient defects and how lipid packing affects membrane disruption by small molecules.

Effects of Kiwifruit Peel Extract and Its Antioxidant Potential on the Quality Characteristics of Beef Sausage

In the wake of arresting consumers’ health concerns associated with synthetic antioxidants used in meat products, kiwifruit peel by-product was explored as a natural antioxidant source in the current study. A lyophilized kiwifruit peel extract (KPE) at various concentrations of KPE1 (1.5%), KPE2 (3%), and KPE3 (4.5%) was incorporated into formulated beef sausages to compare the physicochemical, sensory quality, and antioxidant efficacy to the treatments of control (CT 0% KPE) and butylated hydroxytoluene (BHT 0.01%) during 12 d of refrigerated (4 ± 1 °C) storage. The KPE inclusion levels induced significantly higher yellowness (b*) values than CT and BHT, whereas no negative influence of KPE was revealed for lightness (L*) and redness (a*). The pH values of the KPE treatments were reduced, and cooking yield increased significantly (p < 0.05), in line with the increasing amount of KPE percentages (1.5%, 3%, and 4.5%) compared to CT and BHT samples. E-nose results showed an enhancement in aroma in KPE treatments, compared to BHT and CT, during the storage period. KPE3 treatment showed a constant lesser value in 2-Thiobarbituric acid reactive substances (TBARS) as storage days increased, compared to the CT and BHT samples. Overall, the KPE is effective for antioxidative capacity, and has the potential to be used as a natural antioxidant in beef sausage.

Nutritional Composition and Bioactive Compounds of Basil, Thyme and Sage Plant Additives and Their Functionality on Broiler Thigh Meat Quality

Meat industries across the world are constantly focusing to find natural low-cost additives for the development of novel meat products to meet consumer demand for improving the health benefits. In this study, we investigated the chemical composition and the bioactive compounds of some herbal plants, namely basil, thyme, sage, and their functionality on broiler chicken thigh meat quality. Chemical composition, as well as total antioxidant activity, polyphenols, vitamin E lutein and zeaxanthin and the fatty acids of the plants, were analyzed. According to findings, total polyphenols was 21.53 mg gallic acid/g in basil, 31.73 mg gallic acid/g in thyme and 38.87 mg gallic acid/g in sage. The antioxidant capacity was 19.91 mM Trolox in basil, 54.09 mM Trolox in thyme and 54.09 mM Trolox in sage. Lutein and zeaxanthin from basil was 267.91 mg/kg, 535.79 mg/kg in thyme and 99.89 mg/kg, and vitamin E ranged from 291.71 mg/kg in basil to 379.37 mg/kg in thyme and 148.07 mg/kg in sage, respectively. After, we developed a trial on 120 unsexed broiler chickens (n = 30) which were separated into four groups with six replications of five chickens each: control (C); 1% basil (B); 1% thyme (T) and 1% sage (S). The B, T and S groups deposited significantly higher (p < 0.05) concentration of zinc, polyphenols, antioxidant capacity and vitamin E in meat samples compared with the C group. In the experimental groups, the proportion of total polyunsaturated fatty acids, the ratio of n-6 to n-3 fatty acids, and the ratio of polyunsaturated fatty acids to saturated fatty acids in the thigh muscles were significantly improved (p < 0.05). The tested plants exhibited a significant (p = 0.0007) hypocholesterolemic effect in the meat of the B (45.90 mg/g), T (41.60 mg/g) and S (48.80 mg/kg) experimental groups compared with the C (60.50 mg/g) group. These results support the application of the studied plants as natural sources of additives which could be effective in improving meat quality, from the human consumption perspective.

Quality changes of cooked sausages influenced by the incorporation of a three-component natural antioxidant blend

The aim of this study was to evaluate the influence of triplicate blend of natural antioxidants on the sensorial, physicochemical and microbiological characteristics of cooked sausage. Three antioxidants: sodium L-ascorbate (x1), dihydroquercetin isolate from Larix sibirica Ledeb (x2) and lyophilized ethanol (30%) extract of dry distilled rose (Rosa damascena Mill) petals (x3) were studied in doses 0, 0.05 and 0.1 g/kg. The sensory characteristics, pH, primary products of lipid oxidation expressed by peroxide value and total viable count of the concentration of microorganisms were analysed. The studied parameters were measured on the first and the seventh day of the storage at 0-4°C. After 7 days of storage at 0-4°C it was found that the panel evaluated the highest sensory scores in design point 9 with addition of 0.05 g/kg of the three antioxidants and no difference was found compared to the control (without antioxidants). On the contrary, a minimum peroxide value of 2.88 ± 0.03 µeqO2/kg is achieved by the addition of 0.1 g/kg of the three antioxidants. The total viable count of microorganisms and pH values of the control samples were lower than those with the addition of antioxidants. Additional experiments are needed to optimize the three-component antioxidant blend.

The Structuring of Sage (Salvia officinalis L.) Extract-Incorporating Edible Zein-Based Materials with Antioxidant and Antibacterial Functionality by Solvent Casting versus Electrospinning

In this study, in order to develop zein-based, edible, functional food-contact materials in different forms incorporating sage extract (10, 20, and 30%), solvent casting and electrospinning were employed. The study aimed to assess the effects of the applied techniques and the extract’s incorporation on the materials’ properties. The solvent casting generated continuous and compact films, where the extract’s incorporation provided more homogenous surfaces. The electrospinning resulted in non-woven mats composed of ribbon-like fibers in the range of 1.275–1.829 µm, while the extract’s incorporation provided thinner and branched fibers. The results indicated the compatibility between the materials’ constituents, and efficient and homogenous extract incorporation within the zein matrices, with more probable interactions occurring during the solvent casting. All of the formulations had a high dry matter content, whereas the mats and the formulations incorporating the extract had higher solubility and swelling in water. The films and mats presented similar DPPH^• and ABTS^•+ radical scavenging abilities, while the influence on Staphylococcus aureus and Salmonella enterica subsp. enterica serovar Typhimurium bacteria, and the growth inhibition, were complex. The antioxidant and antibacterial activity of the materials were more potent after the extract’s incorporation. Overall, the results highlight the potential of the developed edible materials for use as food-contact materials with active/bioactive functionality.

Green extraction and characterization of leaves phenolic compounds: a comprehensive review

Although containing significant levels of phenolic compounds (PCs), leaves biomass coming from either forest, agriculture, or the processing industry are considered as waste, which upon disposal, brings in environmental issues. As the demand for PCs in functional food, pharmaceutical, nutraceutical and cosmetic sector is escalating day by day, recovering PCs from leaves biomass would solve both the waste disposal problem while ensuring a valuable "societal health" ingredient thus highly contributing to a sustainable food chain from both economic and environmental perspectives. In our search for environmentally benign, efficient, and cost-cutting techniques for the extraction of PCs, green extraction (GE) is presenting itself as the best option in modern industrial processing. This current review aims to highlight the recent progress, constraints, legislative framework, and future directions in GE and characterization of PCs from leaves, concentrating particularly on five plant species (tea, moringa, stevia, sea buckthorn, and pistacia) based on the screened journals that precisely showed improvements in extraction efficiency along with maintaining extract quality. This overview will serve researchers and relevant industries engaged in the development of suitable techniques for the extraction of PCs with increasing yield.

Plant Extracts for the Control of Listeria monocytogenes in Meat Products

The antimicrobial activity of garlic (Allium sativum L.) and onion (Allium cepa L.) plant active extracts was determined against Listeria monocytogenes in two meat products. Samples of sausages “cacciatore” and cooked ham in vacuum-packaged slices were artificially contaminated, and the presence of Listeria was evaluated during the sausages ripening and throughout the shelf-life of the cooked ham. The test carried out on sausages did not show differences among treated and untreated samples. The antagonistic activity of the plant extracts against the pathogen was probably hidden by the competition from the sausages microbial flora and the pH and the water activity (aw) decrease. On the other hand, the plant extracts determined an initial reduction of about 1.00 log cfu/g of the L. monocytogenes viable count in the cooked ham slices contaminated with 103 cfu/g, but the best result was obtained with the contamination of 102 cfu/g of L. monocytogenes. In addition to the pathogen’s initial decrease, we observed an extension of the lag phase and a reduction of the Listeria growth rate. Considering that the presence of L. monocytogenes during the slicing phase of the cooked ham does not exceed 10 cfu/g, the use of plant extracts can lead to complete pathogen elimination.

Campylobacter Biofilms: Potential of Natural Compounds to Disrupt Campylobacter jejuni Transmission

Microbial biofilms occur naturally in many environmental niches and can be a significant reservoir of infectious microbes in zoonotically transmitted diseases such as that caused by Campylobacter jejuni, the leading cause of acute human bacterial gastroenteritis world-wide. The greatest challenge in reducing the disease caused by this organism is reducing transmission of C. jejuni to humans from poultry via the food chain. Biofilms enhance the stress tolerance and antimicrobial resistance of the microorganisms they harbor and are considered to play a crucial role for Campylobacter spp. survival and transmission to humans. Unconventional approaches to control biofilms and to improve the efficacy of currently used antibiotics are urgently needed. This review summarizes the use plant- and microorganism-derived antimicrobial and antibiofilm compounds such as essential oils, antimicrobial peptides (AMPs), polyphenolic extracts, algae extracts, probiotic-derived factors, d-amino acids (DAs) and glycolipid biosurfactants with potential to control biofilms formed by Campylobacter, and the suggested mechanisms of their action. Further investigation and use of such natural compounds could improve preventative and remedial strategies aimed to limit the transmission of campylobacters and other human pathogens via the food chain.

Effects of Lacticaseibacillus rhamnosus LOCK900 on Development of Volatile Compounds and Sensory Quality of Dry Fermented Sausages

Traditional dry fermented meat products are highly appreciated by consumers. A probiotic starter culture increases their attractiveness through sensory qualities and a potential health-promoting effect. The ability to scale the laboratory solution to industrial conditions is an additional scientific and practical value of a new way of using probiotics in the meat industry. The aim was to evaluate the influence of the probiotic starter culture Lacticaseibacillus rhamnosus LOCK900 on the development of volatile organic compounds and the sensory quality of dry fermented pork sausages during fermentation and refrigeration storage. The microbiological and sensory characteristic (QDA method) and volatile compound (gas chromatography coupled with mass spectrometry: GC–MS) were evaluated. The number of LOCK900 cells during 12 weeks of storage remained above 6 log CFU g⁻¹, making this product a functional food. The addition of probiotic LOCK900 increased the levels of acidic volatile compounds, aldehydes, and esters, which, combined with the additives and spices used, had a positive effect on the sensory properties of ripening sausages. The sausages with LOCK900 were characterised by positive sensory features, and their overall quality remained high during storage and did not differ from that of the control sausages.

Effects of ergothioneine-enriched mushroom extract on oxidative stability, volatile compounds and sensory quality of emulsified sausage

OBJECTIVE

The aim of this work was to assess the effect of ergothioneine (ESH)-enriched mushroom extract on oxidative stability, volatile compounds, and sensory quality of emulsified sausage.

METHODS

The ESH content was determined by high performance liquid chromatography. The antioxidant activity of Flammulina velutipes (F. velutipes) extract was determined through radical-scavenging activity of 1,1 diphenyl-2-picryl-hydrazyl, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) and hydroxyl radicals. Four different groups of emulsified sausage were manufactured: control, no antioxidants; BHA, 0.01% butylated hydroxyanisole; EEME, 0.8% ESH-enriched mushroom (F. velutipes) extract; AE, 0.012% authentic ESH, after storage for 14 days (at 4°C), the quality of sausage including oxidative stability (2-thiobarbituric acid reactive substances and protein carbonyls content), volatile compounds and sensory quality were studied.

RESULTS

It was demonstrated that adding ESH-enriched F. velutipes extract to sausage could effectively prevent lipid and protein oxidation, and its efficacy was equivalent with 0.01% BHA. During meat processing, the ESH mainly contributed to the antioxidative activity of F. velutipes extract. The flavor and sensory attributes of emulsified sausage were improved through adding ESH-enriched F. velutipes extract.

CONCLUSION

Accordingly, the extract of F. velutipes contained high-level of ESH and could be a good antioxidant candidate for processed meat production.

Antioxidant, Antimicrobial and Metmyoglobin Reducing Activity of Artichoke (Cynara scolymus) Powder Extract-Added Minced Meat during Frozen Storage

The present study aimed to investigate the bioactive compounds in artichoke (Cynara scolymus) powder, having antioxidant and antimicrobial activity, and to determine the effectiveness of artichoke (C. scolymus) powder extract within the minced meat. C. scolymus was extracted using two different methods. The method incorporating high phenolic and flavonoid content levels was used in other analyses and the phenolic and flavonoid contents in C. scolymus extract was determined using LC-QTOF-MS. Antioxidant, antimicrobial, and metmyoglobin (metMb) reducing activities and pH values of the extract-added minced meat samples were measured for 10 days during storage. DPPH, FRAP, and ABTS were used in the antioxidant analyses. The antimicrobial activity of C. scolymus extract was evaluated on five different food pathogens by using the disc diffusion method. The most resistant bacterium was found to be Listeria monocytogenes (18.05 mm ± 0.24). The amount of metMb was measured in the minced meat sample that was added to the extract during storage (p < 0.05). MetMb formation and pH value on the sixth day of storage were found to be at lower levels than in the control group. In conclusion, C. scolymus exhibited a good antimicrobial and antioxidant effect and can be used in storing and packaging the food products, especially the meat and meat products.

Effects of dietary inclusion of yerba mate (Ilex paraguariensis) extract on lamb muscle metabolomics and physicochemical properties in meat

This study aimed to evaluate the effect of dietary yerba mate (Ilex paraguariensis) extract (YME) on muscle metabolomics and physicochemical properties of lamb meat. Thirty-six uncastrated male lambs (90 d old) were fed experimental diets, which treatments consisted of 0%, 1%, 2%, and 4% inclusion of YME. Animals were fed for 50 d before slaughter. Muscle and meat samples were collected for metabolomics and meat quality analysis, respectively. The experiment was carried out in a randomized block design and analyzed using orthogonal contrasts. There was a quadratic effect of YME inclusion in tenderness (P < 0.05) and a positive linear effect on meat lightness (P < 0.05). No qualitative changes (P > 0.05) on individual metabolites were observed; however, changes in the quantitative metabolic profile were observed, showing that animals fed 1% and 2% of YME have a greater concentration of desirable endogenous muscle antioxidants, with direct impact on metabolic pathways related to beta-alanine metabolism and glutathione metabolism. Therefore, YME dietary supplementation up to 2% of the diet to lambs had little to no effects on the majority of meat quality traits evaluated; moreover, 4% of YME inclusion negatively affected feed intake and meat quality traits.

Influence of Marination with Aromatic Herbs and Cold Pressed Oils on Black Angus Beef Meat

Beef aging is one of the most common methods used for improving its qualities. The main goal of the present study was to analyse the influence of different cold pressed oils and aromatic herbs during marination process on the nutritional, textural, and sensory attributes of the final grilled sirloin samples. In order to fulfil this goal, methods like GC-MS, HPLC/DAD/ESI-MS, HLPC-RID were performed to quantify fatty acids, phenolic acids, and organic acids, respectively. Textural and sensory analysis were performed with CT 3 Texture Analyser and hedonic test. The results showed high improvement of the meat grilled samples regarding the content of phenolic acids, and textural and sensory characteristics. Pearson values indicate strong positive correlations between raw and grilled samples regarding their content in phenolic acids. Hardness, chewiness, gumminess decreased during marination, meanwhile, resilience, and cohesiveness increased. Sensory analysis highlighted that meat samples marinated with olive oil and rosemary for 120 h reached the highest hedonic score among the tested samples.

Fatty Acid Profile, Total Phenolic Content, and Antioxidant Activity of Niger Seed (Guizotia abyssinica) and Linseed (Linum usitatissimum)

Fatty acid composition and antioxidant content are major determinants of vegetable oil quality. Antioxidants are important food components, and there is an increasing interest of replacing synthetic antioxidants with those from natural sources for food industry. The objective of this study was to evaluate fatty acid composition, total phenolic, carotenoid and chlorophyll contents, and antioxidant capacity of different varieties of two oilseed crops. Five niger seed and eight linseed varieties were used. For the analysis of fatty acid composition of the seed oil, gas chromatography method was used. Standard methods were used for total phenolic, carotenoid and chlorophyll contents, and antioxidant properties. In niger seed oil, linoleic acid (C18:2) was the dominant fatty acid, accounting for 73.3% (variety Esete) to 76.8% (variety Ginchi) of the total fatty acids. In linseed oil, linolenic acid (C18:3) was the dominant fatty acid accounting for 55.7 (variety Chilalo) to 60.1 (variety Belaye-96). The total phenolic content ranged from 22.4 mg GAE/g (variety Esete) to 27.9 mg GAE/g (variety Ginchi) in niger seed and from 20.5 mg GAE/g (variety Belay-96) to 25.4 mg GAE/g (variety Ci-1525) in linseed. In niger seed, variety Fogera had the highest values for FRAP and radical scavenging activity. The carotenoid content also showed significant variation among the varieties ranging from 2.57 (Esete) to 8.08 (Kuyu) μmol/g for niger and 4.13 (Tole) to 8.66 (Belay-96) μmol/g for linseed. The FRAP assay showed that variety Fogera of niger seed and variety Chilalo of linseed came on top among their respective varieties with values of 57.2 and 30.6, respectively. Both niger seed and linseed were shown to be rich in bioactive compounds. However, significant variation was observed among the varieties of each crop and among the two crops in their total phenolic and carotenoid contents as well as ferric reducing potential and radical scavenging capacity. Principal component analysis revealed the presence of more than one group in both niger seed and linseed. Hence, genetic variation among the varieties should be utilized for improving their desirable characteristics through breeding. Both oil crops can be used as the source of antioxidants for replacing synthetic compounds.

Natural Anti-Microbials for Enhanced Microbial Safety and Shelf-Life of Processed Packaged Meat

Microbial food contamination is a major concern for consumers and food industries. Consumers desire nutritious, safe and “clean label” products, free of synthetic preservatives and food industries and food scientists try to meet their demands by finding natural effective alternatives for food preservation. One of the alternatives to synthetic preservatives is the use of natural anti-microbial agents in the food products and/or in the packaging materials. Meat and processed meat products are characteristic examples of products that are highly perishable; hence natural anti-microbials can be used for extending their shelf-life and enhancing their safety. Despite several examples of the successful application of natural anti-microbial agents in meat products reported in research studies, their commercial use remains limited. This review objective is to present an extensive overview of recent research in the field of natural anti-microbials, covering essential oils, plant extracts, flavonoids, animal-derived compounds, organic acids, bacteriocins and nanoparticles. The anti-microbial mode of action of the agents, in situ studies involving meat products, regulations and, limitations for usage and future perspectives are described. The review concludes that naturally derived anti-microbials can potentially support the meat industry to provide “clean label”, nutritious and safe meat products for consumers.

Recent developments of natural antimicrobials and antioxidants on fish and fishery food products

Fish and fishery products (FFP) are highly perishable due to their high nutritional value and moisture content. The spoilage is mainly caused by microorganisms and chemical reactions, especially lipid oxidation, leading to losses in quality and market value. Microbiological and lipid deteriorations of fishery-derived products directly lower their nutritive value and pose the risk of toxicity for human health. Increasing demand for safe FFP brings about the preservation using additives from natural origins without chemical additives due to their safety and strict regulation. Antimicrobials and antioxidants from natural sources have exhibited an excellent control over the growth of microorganisms causing fish spoilage via different mechanisms. They also play a major role in retarding lipid oxidation by acting at various stages of oxidation. Antimicrobials and antioxidants from natural sources are usually regarded as safe with no detrimental effects on the quality attributes of FFP. This review provides recent literature on the different antioxidant and antimicrobial agents from natural sources, focusing on microbial and oxidative spoilage mechanisms, their inhibition system, and their applications to retard spoilage, maintain safety, and extend the shelf life of FFP. Their applications and benefits have been revisited.

Critical overview of the use of plant antioxidants in the meat industry: Opportunities, innovative applications and future perspectives

The number of articles devoted to study the effect of "natural antioxidants" on meat systems has remarkably increased in the last 10 years. Yet, a critical review of literature reveals recurrent flaws in regards to the rationale of the application, the experimental design, the characterisation of the plant sources, the discussion of the molecular mechanisms and of the potential benefits. The selection of the appropriate source of these antioxidants and the identification of their bioactive constituents, are essential to understand their mode of action and set effective and safe doses. The methodological approach should also be planned with care as the recorded effects and main conclusions largely depend on the accuracy and specificity of the methods. This article aims to critically review the recent advances in the application of plant antioxidants in meat and meat products and briefly covers current trends of innovative application and future trends.

Oxidative Stability, Microbial Safety, and Sensory Properties of Flaxseed (Linum usitatissimum L.) Oil Infused with Spices and Herbs

In our study, we assessed whether the addition of basil, fennel, oregano, rosemary, and chili can improve oxidative stability and sensory properties of flaxseed oil (FO) during 180 days of storage or induce oil contamination by microorganisms. Results showed that addition of spices and herbs in FO affected the hydrolytic changes, but far less than 2% of free fatty acids after storage, which was in line with regulations. Further, the addition of spices and herbs in FO decreased peroxide value (even up to 68.7% in FO with oregano) vs. FO whose value increased during storage, indicating increased oxidative stability and prolongation of shelf life of infused oils. The antioxidant activity of the infused oils ranged from 56.40% to 97.66%. In addition, the phenol content was higher in all infused oils (6.81-22.92 mg/kg) vs. FO (5.44 mg/kg), indicating that herbs and spices could scavenge free radicals and inhibit lipid peroxidation, while sensory analysts showed that FO infused with chili had the lowest bitterness intensity. According to the presence of certain microorganisms, results highlighted the need to develop new methods for inactivating microorganisms that would not only provide a microbial safety, but also preserve the beneficial properties of the oils/products.