Effect of adding essential oils of coriander (Coriandrum sativum L.) and hyssop (Hyssopus officinalis L.) on the shelf life of ground beef

Balancing Freshness and Sustainability: Charting a Course for Meat Industry Innovation and Consumer Acceptance

The agribusiness sector is constantly seeking solutions to enhance food security, sustainability, and resilience. Recent estimates indicate that one-third of the total food production remains unused due to waste or limited shelf life, resulting in negative environmental and ethical consequences. Consequently, exploring technological solutions to extend the shelf life of food products could be a crucial option to address this issue. However, the success of these technological solutions is closely linked to the perception of the end-consumers, particularly in the short term. Based on these considerations, this paper presents a systematic literature review of the main technological innovations in the fresh meat industry and of consumers' perceptions of such innovations. Regarding innovative technologies, this review focused on active and smart packaging. Amidst various technological innovations, including the utilization of fundamental matrices and natural additives, a noticeable gap exists in consumer perception studies. This study represents the first comprehensive compilation of research on consumers' perceptions and acceptance of innovations designed to extend the shelf life of fresh meat. Moreover, it sheds light on the existing barriers that hinder the complete embrace of these innovations.

Shelf life extending of probiotic beef patties with polylactic acid-ajwain essential oil films and stress effects on Bacillus coagulans

Meat and meat products are prone to the microbial and chemical spoilage, due to the high nutritional content. This study investigated the effect of polylactic acid (PLA) films incorporated with ajwain essential oil (AEO) on microbial (total viable count [TVC], psychrotrophic bacterial count [PTC], Enterobacteriaceae, Pseudomonas spp., yeast and mold (Y&M), and also Bacillus coagulans [BCG]), chemical (pH, peroxide value [PV], thiobarbituric acid-reactive substance [TBARS], and TVN values), and sensorial properties of beef patties, as well as survivability of BCG during refrigerated storage. Results showed that all microbial counts of samples were significantly increased, except BCG, during storage but the lowest TVC of samples was achieved in samples wrapped with PLA-1% AEO (8 log colony forming units per gram [CFU/g]) at 12th of storage, which is significantly lower than control treatments (10.66 log CFU/g). The best results in all treatments are those wrapped by PLA-1% AEO in all evaluated characteristics. At the final day of storage, PTC (8.82 log CFU/g), Enterobacteriaceae (5.05 log CFU/g), Pseudomonas spp. (9.08 log CFU/g), Y&M (4.69 log CFU/g), and also pH (4.5), PV (5.12 meq/kg), TBARS (2.92 MDA/kg), and TVN (14.43 mgN/100 g) values of PLA-1% AEO treatments were significantly lower than control samples. AEO-PLA films reduce the survival of BCG in raw patties, which reached 6.19 log CFU/g in PLA-1% AEO treatments, although increasing the concentration of AEO in packaging PLA films led to the maintenance of BCG viability during the cooking process by increasing the AEO in PLA films. Overall, results showed shelf life of beef patties is extended 3 days more (150%) by wrapping with PLA films incorporated with 1% AEO.

The Power of the Underutilized and Neglected Medicinal Plants and Herbs of the Middle East

The Middle east and North Africa harbour many native species with pharmaceutical and nutraceutical potential. Since the beginning of history, food and herbal medicinal plants have been an essential part of human lives and the traditional Middle Eastern healthcare system. The notable medicinal plants that have been mentioned in the Bible, which are common in West Asia and some regions of North Africa, are Aloe vera, anise, balm, cassia, cinnamon, cumin, flax, and fig. Chemical components of Aloe vera are aloin, sinapinic acid, catechin, chromone, myricetin, quercitrin and syringic acid. Anethole, safrole, and estragole are the main chemical components of anise. The chemical components of cassia are coumarin, emodin, cinnamyl alcohol, and cinnamaldehyde. The major chemical ingredients of cumin are terpinene, cuminaldehyde, sabinene, thujene, and thymoquinone. The goal of this article is to review the considerable health benefits and pharmaceutical benefits of medicinal herbs and plants that have been neglected and underutilized in the Middle East and North Africa, as well as to promote their utilization. On the basis of the results, the experimented neglected medicinal plant can offer various advantages when used together with conventional medicinal treatments for various health conditions, such as palliative care in managing the side effects of conventional treatments, access to a wider range of treatments, increased patient satisfaction, and improved emotional and mental well-being. Moreover, consuming medicinal plants may help to manage and prevent diabetes, cancer, and heart disease with notable anti-tumor, and anti-inflammatory properties.

Essential Oils and Their Combination with Lactic Acid Bacteria and Bacteriocins to Improve the Safety and Shelf Life of Foods: A Review

The use of plant extracts (e.g., essential oils and their active compounds) represents an interesting alternative to chemical additives and preservatives applied to delay the alteration and oxidation of foods during their storage. Essential oils (EO) are nowadays considered valuable sources of food preservatives as they provide a healthier alternative to synthetic chemicals while serving the same purpose without affecting food quality parameters. The natural antimicrobial molecules found in medicinal plants represent a possible solution against drug-resistant bacteria, which represent a global health problem, especially for foodborne infections. Several solutions related to their application on food have been described, such as incorporation in active packaging or edible film and direct encapsulation. However, the use of bioactive concentrations of plant derivatives may negatively impact the sensorial characteristics of the final product, and to solve this problem, their application has been proposed in combination with other hurdles, including biocontrol agents. Biocontrol agents are microbial cultures capable of producing natural antimicrobials, including bacteriocins, organic acids, volatile organic compounds, and hydrolytic enzymes. The major effect of bacteriocins or bacteriocin-producing LAB (lactic acid bacteria) on food is obtained when their use is combined with other preservation methods. The combined use of EOs and biocontrol agents in fruit and vegetables, meat, and dairy products is becoming more and more important due to growing concerns about potentially dangerous and toxic synthetic additives. The combination of these two hurdles can improve the safety and shelf life (inactivation of spoilage or pathogenic microorganisms) of the final products while maintaining or stabilizing their sensory and nutritional quality. This review critically describes and collects the most updated works regarding the application of EOs in different food sectors and their combination with biocontrol agents and bacteriocins.

The correlation among residual nitrites, biogenic amines, N-nitrosamine formation, and degradation occurrence of punicalagin α/β, rosmarinic acid, carnosol, and carnosic acid in extract-treated sausage during storage

The aim of this study was to investigate the relation between residual α- and β-punicalagin in Punica granatum L.; PPE and rosmarinic acid, carnosol, and carnosic acid in Salvia eremophila (SE) with residual nitrites, biogenic amines (cadaverine, putrescine, and histamine), N-nitrosodimethylamine (NDMA), microbial counts, lipid oxidation indices, and color values in extract-treated sausage over 14 days of storage. Sausage containing SE + nitrite 60 ppm (SSN) showed minimum levels of the residual nitrites (13.14 mg/kg), NDMA (0.74 ± 0.05 μg/kg), and biogenic amine (histamine, 1.8 mg/kg; cadaverine, 3.7 mg/kg; and putrescine, 4.3 mg/kg) due to retarded degradation rate of 285.84-216.44 mg/kg; rosmarinic acid, 41.62-33.16 mg/kg; carnosol, and 88.70-76.73 mg/kg; carnosic acid over storage time. The first-order kinetic model fitted well for the degradation of rosmarinic acid and carnosol acid in SSN sample. TBA value remained below the threshold limit (0.32 mg kg-1) through 14 days for SSN. Second-order and zero-order reaction models had the best agreement with sausages' PV and TBA values, respectively. After 2 weeks of storage, E. coli and Cl. perfringens counts in the SN120 (sausage containing 120 ppm nitrite) and SSN were significantly lower than the other samples (p < .05), with the values 2.1 and 1.5 log cfu/g for SN120 and 2.2 and 1.6 log cfu/g for SSN formulation. Conversely, oxidation indices, residual nitrites, NDMA, and biogenic amine increased in sausage samples containing PPE extracts (SPN) owing to total degradation of α- and β-punicalagin during storage. The results indicated that SE can be used as potential co-preservative by reducing the levels of required nitrite in food industry.

Recent Advances in the Incorporation of Polysaccharides with Antioxidant and Antibacterial Functions to Preserve the Quality and Shelf Life of Meat Products

Meat and meat products are susceptible to various types of natural processes such as oxidative degradation due to their high content of protein and essential amino acids. However, finding solutions to maintain the nutritional and sensory quality of meat and meat products is unavoidable. Hence, there is a pressing need to investigate alternatives to synthetic preservatives, focusing on active biomolecules of natural provenance. Polysaccharides are natural polymers of various sources that exhibit antibacterial and antioxidant properties via a variety of mechanisms, owing to their diversity and structural variation. For this reason, these biomolecules are widely studied in order to improve texture, inhibit the growth of pathogens, and improve the oxidative stability and sensory characteristics of meat products. However, the literature has not addressed their biological activity in meat and meat products. This review summarizes the various sources of polysaccharides, their antioxidant and antibacterial activities (mainly against pathogenic food strains), and their use as natural preservatives to replace synthetic additives in meat and meat products. Special attention is given to the use of polysaccharides to improve the nutritional value of meat, resulting in more nutrient-rich meat products with higher polysaccharide content and less salt, nitrites/nitrates, and cholesterol.

The Essential Oil of Tunisian Halophyte Lobularia maritima: A Natural Food Preservative Agent of Ground Beef Meat

This study was directed towards the investigation of the chemical composition and antimicrobial properties of the essential oil of Tunisian halophyte Lobularia maritime (LmEO). The antibacterial effects against major food-borne pathogenic and food spoilage bacteria were tested using the well diffusion method, followed by the determination of the minimum inhibitory (MIC) and bactericidal (MBC) concentrations. The essential oil has shown strong antimicrobial activity against eight pathogenic strains, which was attributed mostly to predominant constituents of the essential oil: benzyl alcohol, linalool, terpien-4-ol and globulol, as well as to synergistic effects of its major and minor constituents. Considering strong antimicrobial effects of the tested essential oil, it was further tested as a natural alternative to food preservatives, using minced beef meat as a model system. Minced beef meat was spiked with 0.019, 0.038, and 0.076% of the essential oil and stored during 14 days at 4 °C, monitoring its microbiological, physicochemical, and sensory properties. Chemical analyses revealed that meat treated with 0.076% of LmEO at underwent a significant decrease (p < 0.05) in primary and secondary lipid oxidation and reduced metmyoglobin accumulation compared with control samples. Furthermore, microflora proliferation in the meat model system spiked with 0.076% of LmEO was significantly (p < 0.05) reduced in comparison to control. In addition, two multivariate exploratory techniques, namely principal component analysis (PCA) and hierarchical analysis (HCA), were applied to the obtained data sets to describe the relationship between the main characteristics of the meat samples with and without essential oil addition. The chemometric approach highlighted the relationships between meat quality parameters. Overall, results indicated that the essential oil of Lobularia maritima deserves to be considered as a natural preservative in the meat industry.

Spicy and Aromatic Plants for Meat and Meat Analogues Applications

Aromatic and spicy plants are an important factor that contributes not only to improving the taste of meat, meat products, and meat analogues, but also to increasing the nutritional value of the products to which they are added. The aim of this paper is to present the latest information on the bioactive antioxidant and antimicrobial properties of the most commonly used herbs and spices (parsley, dill, basil, oregano, sage, coriander, rosemary, marjoram, tarragon, bay, thyme, and mint) used in the meat and meat analogues industry, or proposed to be used for meat analogues.

Hyssopus Essential Oil: An Update of Its Phytochemistry, Biological Activities, and Safety Profile

The genus Hyssopus is widespread in central Asia, East Mediterranean, and Mongolian areas. It has six main species which are used as herbal remedies, such as Hyssopus officinalis which is used as a condiment and flavoring agent in food industry. The other five species are H. ambiguus, H. cuspidatus, H. latilabiatus, H. macranthus, and H. seravschanicus. Its species are used in the treatment of various ailments such as cold, cough, loss of appetite, fungal infection, and spasmodic condition. Its constituents especially essential oils are popularly used as an additive in beverages, foods, and cosmetics. The volatile constituents are used for aroma in the food industry, cosmetic industry, and household products. The important active constituents in its essential oils are β-pinene, pinocamphone, isopinocamphone, and other terpenoids. Hyssopus genus is also bundled with other secondary metabolites including flavonoids luteolin, quercetin, apigenin, and their glucosides, as well as phenolic compounds including ferulic, p-hydroxy-benzoic acid, protocatechuic acid, chlorogenic, and caffeic acid. Combinedly, the extracts of Hyssopus are reported to have potential antiviral and antifungal activities proven using in vitro studies, whereas in vivo investigations have reported the crucial role of Hyssopus extracts in plasma membrane relaxation, cytotoxic, and sedative effects. This plant is believed to be relatively safe at levels commonly used in foods; nevertheless, more studies are needed to determine the safety profile.

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.

Evaluation of the potential of protective cultures to extend the microbial shelf-life of chilled lamb meat

The use of protective cultures to inhibit spoilage bacteria is a promising natural preservation technique to extend the shelf-life of fresh meat. This study evaluated the effectiveness of six food-grade protective cultures (containing different combinations of Lactobacillus sakei, Pediococcus pentosaceus, Staphylococcus xylosus, and Staphylococcus carnosus) on naturally contaminated chill-stored (4 °C) lamb meat in different packaging systems. Only slight reductions of common meat spoilage bacteria Brochothrix thermosphacta, Pseudomonas spp., and Enterobacteriaceae were observed in culture-treated samples stored in modified atmosphere packaging (80% O₂:20% CO₂). Greater inhibitory effects were found in vacuum-packed lamb, with mixed cultures containing either L. sakei, S. carnosus, and S. xylosus or S. carnosus and L. sakei causing the most significant reductions. Protective cultures did not adversely affect meat color or pH. This study demonstrated the potential of protective cultures comprising lactic acid bacteria and coagulase-negative staphylococci in controlling microbial spoilage of lamb and, by inference, other types of meat as a natural solution for shelf-life extension.

Antibacterial Activity of Rosmarinus officinalis against Multidrug-Resistant Clinical Isolates and Meat-Borne Pathogens

Background

In developing countries, the prevalence of bacterial infections is quite rampant due to several factors such as the HIV/AIDS pandemic, lack of hygiene, overcrowding, and resistance to conventional antimicrobials. Hence the use of plant-based antimicrobial agents could provide a low-cost alternative therapy. Rosmarinus officinalis is reputed as a medicinal plant in Ethiopia; however, its antibacterial activity against many of the clinical isolates remains overlooked.

Methods

Tender foliage of R. officinalis was collected and extracted in ethanol (EtOH) and evaluated for their antimicrobial activity against ten multidrug-resistant (MDR) clinical isolates, human type culture pathogens, and meat-borne bacterial isolates by employing agar well diffusion assay.

Results

EtOH extract of R. officinalis efficiently subdued the growth of all tested MDR clinical isolates in varying degrees. Salmonella sp. and Staphylococcus aureus were found to be the most sensitive clinical isolates. Likewise, it efficiently repressed the growth of meat-borne pathogens, particularly, S. aureus and Salmonella sp. showing its potentiality to be used as a natural antibacterial agent in the meat processing industry. The mechanism of antibiosis of plant extract against meat-borne pathogens is inferred to be bactericidal. Chemical constituents of the crude plant extract were analysed by Gas Chromatography-Mass Spectroscopy (GC-MS), Fourier Transform Infrared (FT-IR), and UV-visible spectroscopy showing genkwanin (26%), camphor (13%), endo-borneol (13%), alpha-terpineol (12%), and hydroxyhydrocaffeic acid (13%) as the major compounds.

Conclusion

Overall results of the present study conclude that R. officinalis could be an excellent source of antimicrobial agents for the management of drug-resistant bacteria as well as meat-borne pathogens.

Chemical composition, extraction sources and action mechanisms of essential oils: Natural preservative and limitations of use in meat products

The antimicrobial activity of essential oils (EO) is associated with the presence of secondary metabolites synthesized by plants. Its mechanism of action involves the interaction of its hydrophobic components with the lipids present in the cell membrane of microorganism, resulting in metabolic damages and cell death. Spoilage and pathogenic microorganisms are contaminants in meat and meat products with considerable impacts on food quality and safety. Research shows the potential of applying essential oils in the preservation of meat food systems as compounds of low toxicity, extracted from a natural source, and as an alternative to consumer demand for healthy foods with a more natural appeal. In addition, there is a great diversity of plants from which essential oils can be extracted, whose antimicrobial activity in vitro and in meat and meat products has been proven.

Microbial biopreservatives for controlling the spoilage of beef and lamb meat: their application and effects on meat quality

Biopreservation is a recognized natural method for controlling the growth of undesirable bacteria on fresh meat. It offers the potential to inhibit spoilage bacteria and extend meat shelf-life, but this aspect has been much less studied compared to using the approach to target pathogenic bacteria. This review provides comprehensive information on the application of biopreservatives of microbial origin, mainly bacteriocins and protective cultures, in relation to bacterial spoilage of beef and lamb meat. The sensory effect of these biopreservatives, an aspect that often receives less attention in microbiological studies, is also reviewed. Microbial biopreservatives were found to be able to retard the growth of the major meat spoilage bacteria, Brochothrix thermosphacta, Pseudomonas spp., and Enterobacteriaceae. Their addition did not have any discernible negative impact on the sensory properties of meat, whether assessed by human sensory panels or instrumental and chemical analyses. Although results are promising, the concept of biopreservation for controlling spoilage bacteria on fresh meat is still in its infancy. Studies in this area are still lacking, especially for lamb. Biopreservatives need more testing under conditions representative of commercial meat production, along with studies of any possible sensory effects, in order to validate their potential for large-scale industrial applications.

Emergency Food Product Packaging by Pectin-Based Antimicrobial Coatings Functionalized by Pomegranate Peel Extracts

Emergency food products (EFPs) or energy bars are used in critical situations, such as natural disasters, to promote crisis management. EFPs require sophisticated packaging strategies. Edible coatings incorporated with natural antimicrobial agents could be considered as active packaging materials for increasing EFP safety. In this study, pectin-based coatings incorporated with pomegranate peel extracts were used to protect energy bars. Initially, total phenolic contents and antimicrobial and antioxidant properties of aqueous and ethanolic pomegranate peel extracts (PPEs) were determined. Also, PPEs were analyzed by HPLC. In the next step, the extracts were incorporated into the matrix of edible coatings as active substances. The sensory properties and microbial contamination of coated energy bars were investigated during 30 days of storage. Sixteen phenolic substances were detected in the extracts with gallic acid, ellagic acid, caffeic acid, coumaric acid, and quercetin as major ingredients. The ethanolic extract exhibited higher concentrations for all phenolic compounds. The results indicated that the ethanolic extract showed inhibitory effects on S. aureus and E. coli at concentrations of 30 and 50 mg/ml, and the aqueous extract's inhibitory effects were observed at concentrations of 50 and 80 mg/ml, respectively. The antioxidant and antibacterial effects could be attributed to high phenolic content and a combination of different substances. Microbial and sensory tests performed on coated energy bars showed that the active coatings were able to control and reduce the population of microorganisms during storage without adversely affecting sensory properties.

Comparative Effects of Carum copticum Essential Oil on Bacterial Growth and Shiga-Toxin Gene Expression of Escherichia coli O157:H7 at Abused Refrigerated Temperatures

Abused refrigerated temperatures are described as unacceptable deviations from the optimal temperature, occurring frequently during transportation of food products. Escherichia coli O157:H7 is a serious contaminant of meats and meat products due to its ability to grow at abused temperatures (> 10 °C). The aim of this study was to evaluate the antibacterial activity of Carum copticum essential oil for the control of Escherichia coli O157:H7 using laboratory media and minced beef at severe abused refrigerated temperature (15 °C). A comparative quantitative reverse transcription real-time PCR was used to assess effects of temperature and Carum copticum essential oil at sub-minimum inhibitory concentrations on bacterial growth and Shiga-toxin gene (stx1A and stx2A) expression. Results indicated that Carum copticum essential oil inhibited growth of E. coli O157:H7 in tryptone soy broth (TSB) media at all sub-MIC values until Hour 48. However, bacterial population increased progressively until Hour 72 at essential oil concentration of 0.75% (ml g^-1) and reached 8.6 log CFU g^-1 in minced beef. The essential oil at concentration of 0.005% (ml g^-1) increased stx gene expression at all times, but increased stx gene expression (0.015%) at Hour 24 in TSB media. The expression rate of stx1A in minced beef decreased progressively (10.39 and 7.67 folds for 0.5 and 0.75%, respectively) and expression of stx2A was variable in minced beef during storage. In conclusion, results from this study have shown that effects of Carum copticum essential oil on growth and virulence gene expression are not necessarily correlated and temperature, essential oil concentration, investigated gene type, and bacterial growth environment (in vivo or in vitro) are effective as well.

Research Note: Microbial inactivation of raw chicken meat by supercritical carbon dioxide treatment alone and in combination with fresh culinary herbs

The objective of the present study was to assess the potential synergistic effect between supercritical carbon dioxide (SC-CO₂) and fresh culinary herbs (Coriandrum sativum and Rosmarinus officinalis) on the microbial inactivation of raw chicken meat. The microbiological inactivation was performed on Escherichia coli and natural flora (total mesophilic bacteria, yeasts, and molds). High pressure treatments were carried out at 40°C, 80 or 140 bar from 15 to 45 min. Microbial inactivation had a strong dependence on treatment time, achieving 1.4 log CFU/g reduction of E. coli after 15 min, and up to 5 log after 45 min, while a pressure increase from 80 up to 140 bar was not significant on the microbial inactivation. Mesophilic microorganisms were strongly reduced (>2.6 log CFU/g) after 45 min, and yeasts and molds were below the detection limits of the technique (<100 CFU/g) in most cases. The combination of fresh herbs together with SC-CO₂ treatment did not significantly increase the inactivation of either E. coli or natural flora, which was similar to the SC-CO₂ alone. The synergistic effect was obtained on the inactivation of E. coli using a proper concentration of coriander essential oil (EO) (0.5% v/w), while rosemary EO did not show a significant effect. Color analysis after the treatment showed an increment of lightness (L*), and a decrease of redness (a*) on the surface of the sample, making the product visually similar to cooked meat. Texture analysis demonstrated the modification of the texture parameters as a function of the process pressure making the meat more similar to the cooked one.

Hyperbaric storage at variable room temperature - a new preservation methodology for minced meat compared to refrigeration

Hyperbaric storage (HS) at variable room temperature (RT) has been proposed as an alternative to refrigeration at atmospheric pressure (RF/AP) for food preservation. Little information is available regarding the effect of HS in meat products. In this study the RT/HS effect was evaluated at 100 MPa and variable RT (≈20 °C) for minced meat preservation up to 24 h, initially for one batch. A further two different batches were studied independently. Microbiological and physicochemical parameters were analyzed to assess the feasibility of RT/HS, using storage at RF/AP and variable RT/AP (≈20 °C), for comparison. A post-hyperbaric storage (post-HS) was also tested over 4 days at RF/AP. For the first batch the results showed that RT/HS allowed a decrease of the total aerobic mesophile value (P < 0.05) when compared to the initial sample, whereas at RF/AP and RT/AP, values increased to > 6 Log CFU g^-1 after 24 h. Similarly, Enterobacteriaceae increased > 1 and > 2 Log CFU g^-1 at RF/AP and RT/AP, respectively, while yeasts and molds presented similar and lower overall loads compared to the initial samples for all storage conditions, whereas RT/HS always allowed lower counts to be obtained. Regarding pH, lipid oxidation, and color parameters, RT/HS did not cause significant changes when compared to RF/AP, except after 24 h, where pH increased. The three batches presented similar results, the differences observed being mainly due to the heterogeneity of the samples. RT/HS is a potential quasi-energetic costless alternative to RF for at least short-term preservation of minced meat. © 2018 Society of Chemical Industry.

Sono hydrodistillation for isolation of citronella oil: A symbiotic effect of sonication and hydrodistillation towards energy efficiency and environment friendliness

Environmental benign approach for extraction of essential oil was made. An essential oil rich in citronellol, linalool and citronellal was extracted from the leaves of Cymbopogon winterianus using a clean hybrid extraction technique, sono hydrodistillation. Sono hydrodistillation combines ultrasonic waves along with conventional hydrodistillation process to have symbiotic outcomes in terms of process improvement. Significant process parameters such as size of the plant material, extraction time, power, ultrasound amplitude, pulse interval and solid loading were investigated independently to study the effect on yield of oil and composition of oil. The water residue remained after extraction of volatile oil was analyzed using Folin-Ciocalteu method to determine the total phenolic content (TPC) which would help in assessing the residue as a useful by-product. Substantial reduction in time was observed with the inclusion of ultrasound compared to conventional hydrodistillation. Further, to optimize the extraction conditions, observe interactive effects of various parameters and develop mathematical model, response surface methodology was employed. The maximum yield of oil was found to be 4.118% (w/w) at 21 min extraction time, 5 g solid loading, 250 mL water volume, 500 W heating mantle power, 70% ultrasonic amplitude and 10:50 pulse interval. Total phenolic content was 13.84 mg GAE/g DM. The citronella oil was found to be composed of 27.47% of linalool, 11.52% of citronellal, 34.25% citronellol and 11.15% of elemol. Extraction time, solid loading and pulse interval had the significant influence on the yield of oil and total phenolic contents. Microscopic analysis has assisted in envisaging the probable mechanism indicating the role of sonication for rapid extraction. This novel technique was compared with the conventional hydrodistillation to ascertain the impact towards process intensification. Sono hydrodistillation was found to be a greener and cleaner process as energy consumption has been reduced by 40% while carbon footprint has shrunken by 47%.

Effect of essential oils of Lamiaceae plants on the Rhizopus spp

The aim of this study was to evaluate the fungicidal effect of eleven essential oils against six isolates of the genus Rhizopus. Isolates were obtained from various moldy foods (chestnut, bread, strawberry, nectarine, blackberry and cherry tomatoes).  The essential oils used in this study were extracts of basil (Oscimum basilicum L.), hyssop (Hyssopus officinalis L.), lavender (Lavandula angustifolia MILLER.), marjoram (Origanum majorana L.), mint (Mentha piperita L.), oregano (Origanum vulgare L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.), summer savory (Satureja hortensis L.), thyme (Thymus vulgaris L.) and wild thyme (Thymus serpyllum L.). Semi-quantitative composition of the essential oil samples was determined by gas chromatography coupled with mass spectrometry (GC-MS). The GC-MS analyses of the essential oils led to identification of 139 compounds, of which 49 were presented in ≥1% amount in at least one essential oil. The antifungal activity of essential oils against the Rhizopus spp. was determined, using micro-atmosphere method (0.625 μL.ml-1 of air), during 7 days. Seven essential oils: thyme, mint, summer savory, lavender, marjoram, oregano and wild thyme completely inhibited the growth of all isolates. Other essential oils have different effects on the growth of isolates. Basil essential oil stimulated growth of two isolates on the second day of cultivation. The growth of other isolates was, by contrast, inhibited by this essential oil in the same time of cultivation. Hyssop essential oil completely inhibited growth of two isolates, other 4 isolates were inhibited to fourth day of cultivation. In conclusion, certain essential oils are highly effective in vapour phase and can be used in another test of their antifungal activity and could be used in control of Rhizopus spp. or other fungal pathogens.

Identification of the Anti-Aflatoxinogenic Activity of Micromeria graeca and Elucidation of Its Molecular Mechanism in Aspergillus flavus

Of all the food-contaminating mycotoxins, aflatoxins, and most notably aflatoxin B₁ (AFB₁), are found to be the most toxic and economically costly. Green farming is striving to replace fungicides and develop natural preventive strategies to minimize crop contamination by these toxic fungal metabolites. In this study, we demonstrated that an aqueous extract of the medicinal plant Micromeria graeca—known as hyssop—completely inhibits aflatoxin production by Aspergillus flavus without reducing fungal growth. The molecular inhibitory mechanism was explored by analyzing the expression of 61 genes, including 27 aflatoxin biosynthesis cluster genes and 34 secondary metabolism regulatory genes. This analysis revealed a three-fold down-regulation of aflR and aflS encoding the two internal cluster co-activators, resulting in a drastic repression of all aflatoxin biosynthesis genes. Hyssop also targeted fifteen regulatory genes, including veA and mtfA, two major global-regulating transcription factors. The effect of this extract is also linked to a transcriptomic variation of several genes required for the response to oxidative stress such as msnA, srrA, catA, cat2, sod1, mnsod, and stuA. In conclusion, hyssop inhibits AFB₁ synthesis at the transcriptomic level. This aqueous extract is a promising natural-based solution to control AFB₁ contamination.

Antimicrobial activity of coriander oil and its effectiveness as food preservative

ABTRACT Foodborne illness represents a major economic burden worldwide and a serious public health threat, with around 48 million people affected and 3,000 death each year only in the USA. One of the possible strategies to reduce foodborne infections is the development of effective preservation strategies capable of eradicating microbial contamination of foods. Over the last years, new challenges for the food industry have arisen such as the increase of antimicrobial resistance of foodborne pathogens to common preservatives and consumers demand for naturally based products. In order to overcome this, new approaches using natural or bio-based products as food preservatives need to be investigated. Coriander (Coriandrum sativum L.) is a well-known herb widely used as spice, or in folk medicine, and in the pharmacy and food industries. Coriander seed oil is the world's second most relevant essential oil, exhibiting antimicrobial activity against Gram-positive and Gram-negative bacteria, some yeasts, dermatophytes and filamentous fungi. This review highlights coriander oil antimicrobial activity and possible mechanisms of action in microbial cells and discusses the ability of coriander oil usage as a food preservative, pointing out possible paths for the successful evolution for these strategies towards a successful development of a food preservation strategy using coriander oil.

Antibacterial Activity and Mechanism of Action of Black Pepper Essential Oil on Meat-Borne Escherichia coli

The aim of this study was to investigate the antibacterial activity of black pepper essential oil (BPEO) on Escherichia coli, further evaluate the potential mechanism of action. Results showed that the minimum inhibition concentration (MIC) of BPEO was 1.0 μL/mL. The diameter of inhibition zone values were with range from 17.12 to 26.13 mm. 2 × MIC treatments had lower membrane potential and shorter kill-time than 1 × MIC, while control had the highest values. E. coli treated with BPEO became deformed, pitted, shriveled, adhesive, and broken. 2 × MIC exhibited the greatest electric conductivity at 1, 3, 5, 7, 9, 11, and 13 h, leaked DNA materials at 4, 8, 12, 16, 20, 24, and 28 h, proteins at 4, 6, 8, 10, 12, 14, and 16 h, potassium ion at 0, 0.5, 1, 1.5, and 2 h, phosphate ion at 0.5, 1, 1.5, and 2 h and ATP (P < 0.05); 1 × MIC had higher values than control. BPEO led to the leakage, disorder and death by breaking cell membrane. This study suggested that the BPEO has potential as the natural antibacterial agent in meat industry.

Influence of fat addition on the antimicrobial activity of sodium lactate, lauric arginate and methylparaben in minced meat

A minced meat model system containing three different fat levels (0, 15, and 50 wt.%) was used to evaluate the antimicrobial efficacy of three antimicrobials with different aqueous solubilities (sodium lactate>lauric arginate (Nα-lauroyl-L-arginine ethyl ester, LAE)>methylparaben). Various concentrations of sodium lactate (20, 40, and 60 mg/g), lauric arginate (0.5, 1, 1.5, 2.0, and 2.5 mg/g) and methylparaben (0.1, 0.5, 1.0, and 2.0 mg/g) were used to evaluate the antimicrobial activity against natural meat microbiota (total aerobic mesophilic colony counts, coliform bacteria, and lactic acid bacteria). The results indicate that the three antimicrobials tested are influenced at different strengths by the changes of the fat addition of the minced meat. The antimicrobial efficacy of LAE and methylparaben is increased by a higher fat content in the meat batter, whereas for lactate no clear lactate proportionality relationship can be seen. This structure sensitivity is most strongly pronounced with lauric arginate, which we attributed to the amphiphilic character of the molecule.

Evaluation of usage of essential oils instead of spices in meat ball formulation for controlling Salmonella spp

The purpose of this study was to show the efficacy of essential oils (EOs) in meat balls instead of spices because of their high antimicrobial effect and to evaluate the antimicrobial effect of Origanum onites and Ocimum basilicum EOs against Salmonella Typhimurium in minced beef (20% fat) stored at 4 ℃ for seven days. This is the first study about use of O. basilicum EO in minced beef against bacterial pathogens. Both EOs inhibit microorganisms in in vitro antibacterial tests. Minimum inhibitory concentration (MIC) values of EOs were determined. The lowest MIC values were obtained with O. onites EO 0.6 µl/ml against S. Typhimurium strains. The MIC values of O. basilicum EO 0.25 µl/ml against microorganisms. Both EOs showed a significant decrease in microorganisms inoculated in minced beef at end of storage. The concentration of the both EOs at 20 µg/mg and 10 µg/mg showed stronger antimicrobial activity against bacterial cocktail of S. Typhimurium in beef; however, the higher concentrations caused alterations in the organoleptic properties of meatballs. The results of the present study indicate that O. onites and O. basilicum EOs may be used in combination with each other and different food preservation systems in meat ball formulation.

Reduction of microbiological risk in minced meat by a combination of natural antimicrobials

BACKGROUND

Responsibility for food safety must be taken through the entire food-production chain, to avoid consumer cross-contamination. The antimicrobial activities of an Alpinia katsumadai seed extract and epigallocatechin gallate (EGCG), and their combination, were evaluated against individual food-borne pathogenic strains of Listeria monocytogenes, Escherichia coli and Campylobacter jejuni, individually and as a cocktail, in chicken-meat juice and sterile minced meat as food models, and in minced meat with the naturally present microflora, as an actual food sample.

RESULTS

The antimicrobial combination of the A. katsumadai extract and EGCG was the most efficient for C. jejuni growth inhibition, followed by inhibition of L. monocytogenes, which was reduced more efficiently in the bacterial cocktail than as an individual strain. The antimicrobial combination added to minced meat at refrigeration temperatures used in the food chain (8 °C) revealed inhibition of these pathogens and inhibition of the naturally present bacteria after 5 days.

CONCLUSIONS

The antibacterial efficiencies of the tested combinations are influenced by storage temperature. Food safety can be improved by using the appropriate combination of natural antimicrobials to reduce the microbiological risk of minced meat.

Effects of Ocimum basilicum Linn essential oil and sodium hexametaphosphate on the shelf life of fresh chicken sausage

Although consumers and the food industry have an interest in reducing the use of synthetic additives, the consumption of processed meat in Brazil has been increasing because of the easy preparation and low cost. Owing to the antimicrobial and antioxidative properties of Ocimum basilicum essential oil (EO), it has potential applications in food products. Polyphosphates are already used in meat processing with the goal of improving the quality of the products. The aim of this work was to assess the effects of sodium hexametaphosphate (SHMP) and O. basilicum EO, when added separately or together, on physical, chemical, and microbiological parameters during the shelf life of chicken sausage. We also performed sensory analysis of the product prepared in this manner. Six different treatments were produced in which the substances were tested together or separately, and the content of EO was 0.3 or 0.03%. The samples were analyzed after 1, 7, and 15 days of storage at 4°C. An increase in pH on days 7 and 15 in samples that contained SHMP was observed. In the samples that contained either 0.3 or 0.03% EO, coliforms were inhibited throughout the study period (P < 0.05), which was not observed in samples with EO plus SHMP, thus demonstrating that the stabilizer blocked the antibacterial action of EO. There was a reduction in the cook loss and increased compressive force in the samples with 0.5% SHMP, contributing to greater juiciness of the product. The EO had substantial impact on acceptability of samples, but it did not influence the activities already described of polyphosphate.