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Abstract The rising packaging industry together with global demand for sustainable production has increased the interest in developing biodegradable packaging materials. The aim of the study was to develop edible films based on pectin, gelatin, and hydroxypropyl methylcellulose and evaluate their applicability as biodegradable packaging materials for gilthead seabream fillets. Mechanical properties, water barriers, wettability of the films through contact angle measurement, optical, and UV–Vis barrier properties were evaluated for food packaging applications. The effective blend of polysaccharide and protein film-forming solutions was confirmed by the produced films with excellent optical properties, acceptable mechanical properties and adequate barriers to water vapor. The contact angle for pectin based and gelatin based films were higher than 90° indicating the hydrophobic films, while HPMC based films had contact angle lower than 90°. The produced films were tested as alternative and environmentally friendly packaging materials for gilthead seabream fillets during refrigerated storage. All tested packaging conditions resulted in similar shelf-life in packed gilthead seabream fillets (i.e. 7–8 days at 2 °C). The results showed that the developed films may reduce the use of conventional petroleum-based food packaging materials without affecting the shelf-life of fish.

The present work aimed to evaluate and mathematically model the effect of temperature on Morganella morganii growth and histamine formation in farmed mullet (Mugil cephalus) during refrigerated storage (at constant temperatures, T = 0, 2.5, 5, 10, and 15 °C) and to validate the developed models at non-constant temperature conditions (effective temperature Teff = 7.4 °C). Shelf life evaluation of chilled mullet was also carried out based on microbial spoilage, sensory degradation, and total volatile nitrogen (TVB-N) determination. Spoilage of mullet during refrigerated storage was co-dominated by Pseudomonas spp. and Enterobacteriaceae growth. Sensory rejection (score 5 for overall impression) and the end of shelf life coincided with a total microbial load of 8 log cfu/g. The shelf life of chilled mullet was estimated at 15, 11, 7, 3, and 1.5 days at 0, 2.5, 5, 10, and 15 °C, respectively. At T 0–5 °C, the time of sensory rejection coincided with TVB-N concentrations of 10.2–12.3 mg·100 g−1, and at 10–15 °C, the samples were sensorially rejected before TVB-N development. At storage temperatures < 5 °C, sensory rejection was observed well before histamine levels reached a concentration of 50 mg/kg fish flesh. However, when abusive temperatures prevail, histamine should be considered as a risk factor for the human consumption of mullet.

Listeria monocytogenes (Lm) is responsible for listeriosis, a serious foodborne disease, with high hospitalization and mortality rates worldwide. The main cause of listeriosis in humans is the consumption of ready-to-eat (RTE) foods; Commission Regulation (EC) No 2073/2005 establishes microbiological criteria for Lm in RTE foods. Raw fish products are widely consumed, e.g., in sushi and various seafood recipes (e.g., carpaccio, sashimi, maki, nigiri, tartare, etc.), but are not subjected to RTE food safety criteria. The aim of our study was to assess the growth potential of Lm in raw sea bass fillets obtained from a leading aquaculture company in Greece. In order to assess the growth of Lm in raw sea bass fillets, we applied the “challenge test”, a scientific experiment designed to assess the growth of Lm within a specific food product under controlled conditions. According to our results, and taking into consideration the health risk for the listeriosis-vulnerable population, raw fish products utilized in the preparation of RTE foods, including sushi and an array of seafood dishes, should be incorporated in the Category of Safety Criteria of Regulation (EC) No 2073/2005 “Ready-to-eat food able to support the growth of Listeria monocytogenes”.

The objective of this study was to evaluate the effect of modified atmosphere packaging (MAP) on fish skin, gills and intestines bacterial microbiome.Whole gilthead seabream was packed aerobically or under modified atmospheres (60% CO2, 30% N2, 10% O2) and stored isothermally at 0 °C. Next Generation Sequencing (NGS) analysis was applied for the characterization of fish microbiome on fish skin, gills, and intestines initially (time of packaging, 1 day after harvesting) and after 10 days of isothermal storage at 0 °C. NGS results indicated statistically significant differences in families’ richness and diversity in the tested fish tissues between aerobic and MAP packaging during storage at 0 °C. The most persistent bacteria were Proteobacteria for both packaging types. For fish skin microbiota, the initially prevailing families were Comamonadaceae, Enterobacteriaceae and Moraxellaceae while in the intestines Comamonadaceae, Anaplasmataceae, Bacillaceae and Enterobacteriaceae were the dominant bacteria. At the end of storage period, the fish microbiota was dominated by psychotropic and psychrophilic families (Pseudoalteromonadaceae, Psychromonadaceae, and Shewanellaceae), while families such as Comamonadaceae were persistent under MAP conditions. By 8 days of fish storage at 0 °C, ΜΑΡ samples exhibited higher sensory scorings than the respective aerobically stored fish, indicating better retention of fish freshness and fish quality attributes under MAP. Based on the results of the study, MAP modified significantly the microbiological status and extended the shelf life of fish. NGS was a powerful tool that provided a more complete assessment compared to a culture-based analysis.

The objective of the study was to investigate the efficiency of slurry ice during harvesting and transportation of European sea bass (Dicentrarchus labrax) to retain flesh quality and extend shelf life, compared with conventional flake ice. Fish was slaughtered and transported in different mixtures of slurry ice and conventional flake ice (C: slaughtered and transported in 100% flake ice-Control samples, SC: slaughtered in 100% slurry ice and transported in 100% flake ice, S50: slaughtered and transported in 50% slurry ice-50% flake ice, S100: slaughtered and transported in 100% slurry ice) and subsequently stored under controlled isothermal conditions at 0 °C for shelf life modelling and flesh quality evaluation (proteolytic enzymes). The replacement of conventional flake ice with slurry ice as a slaughtering method led to improved quality stability during subsequent refrigerated storage and shelf life extension, in terms of microbial growth, flesh quality and sensory degradation of fish. Based on microbial growth, the shelf life of C samples was found to be 19 days, whereas the shelf life of S50/S100 and SC was 21 and 25 days, respectively, showing that the replacement of flake ice with slurry ice resulted in 2–6 days shelf life extension of whole sea bass stored at 0 °C. The use of slurry ice at slaughter and flake ice in transportation was accompanied by low activities and late peaks of all four enzymes that is expected to lead to delayed proteolytic degradation and extended freshness.

Fresh fish, and especially fatty species, are highly perishable due to oxidative deterioration of fish flesh and the elevated microbial load on fish surface. The implementation of a variety of “mild hurdles” may significantly decrease the rates of fish chemical degradation and microbiological spoilage, by better retaining the initial quality, compared to more intense preservation techniques. The aim of this work is the comparative study of different, single or combined, treatments at 15 °C on the quality and shelf life of chilled eel fillets. Fish fillets were treated using osmotic solutions consisting of glycerol (30%–40%–45%) and 5% NaCl with and without former antioxidant impregnation by using Rosemary Serum. In all cases, water activity decreased to approximately 0.90 after 420 min of osmotic treatment. Untreated and osmotically treated fish fillets were subsequently stored at 4 °C and their stability under chill conditions was assessed based on microbial growth and oxidative deterioration. Microbial growth of treated samples was significantly delayed, especially due to the osmotic step (OS) and the derived water activity decrease. Lipid oxidation, a major cause of rejection for fatty fish such as eel, was greatly inhibited in treated fillets, owing to both ‘hurdles’, aw lowering (OS) and antioxidant impregnation with rosemary serum (RS/OS), showing the synergistic effect of these successive procedures. Shelf life of treated eel fillets exhibited a more than 10-fold increase, as compared to the untreated samples, based on chemical composition and a 2 to 3-fold shelf life improvement, in terms of microbial growth.

An essential aspect of product quality of aquatic foods is the rapid and accurate identification of bacterial species. From this perspective omics technologies prove to be very useful in the assessment of the quality and safety of seafood products. Such technologies can identify and detect low levels of contamination by pathogenic and spoilage bacteria and can be used to study the effects caused by processing and storage of seafood products. The integration of food processing with the monitoring of the microbial characteristics using conventional microbiological assays, coupled to molecular techniques may establish the baseline for the development of quicker and more sensitive and reliable methods for seafood safety screening. The use of combined omics technologies, including metagenomics, proteomics and metabolomics, coupled to conventional quality indices such as colour, texture and flavour offer a new tool for novel processing optimization to ensure seafood quality. The aim of this brief review is to outline how omics technologies can generate novel tools for integration into seafood processing and quality control. Considering that the main aspect of the review is the improvement of safety and quality of the final product, from production to consumption, emphasis is given to microbial identification and metabolite detection, the evaluation of the allergenic capacity of fish and seafood and optimization of postharvest processing. Deployment of omics for identification of potential microalgal products of relevance to seafood quality and safety is also considered.

In the present study, selected pathogenic (Salmonella Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Listeria monocytogenes, Bacillus cereus, and Staphylococcus aureus) and nonpathogenic (Pseudomonas fragi, Pseudomonas fluorescens, Brochothrix thermosphacta, Bacillus subtilis, Lactiplantibacillus plantarum, and Leuconostoc mesenteroides) bacteria were subjected in vitro in cold atmospheric pressure plasma (CAPP) treatment for up to 15 min and the changes in the surviving microbial population were determined. Plasma treatments were carried out by a plasma jet device, operating with argon (Ar) as carrier gas under constant flow (4.0 L/min) at a frequency of 1 MHz and an electrical voltage of 2–6 kV. Microbial inactivation data were modelled using linear and nonlinear (Geeraerd, Weibull) models, through which the corresponding kinetic parameters were calculated. After 15 min of exposure to plasma radiation, the total reduction in the bacterial populations was 2.12 log10 CFU mL−1 for P. fragi, 1.77 log10 CFU mL−1 for P. fluorescens, 2.30 log10 CFU mL−1 for B. thermosphacta, 1.58 log10 CFU mL−1 for B. subtilis, 1.31 log10 CFU mL−1 for L. plantarum, 3.80 log10 CFU mL−1 for L. mesenteroides (highest reduction observed), 1.12 log10 CFU mL−1 for S. Typhimurium, 1.18 log10 CFU mL−1 for E. coli, 1.43 log10 CFU mL−1 for L. monocytogenes, 1.32 log10 CFU mL−1 for B. cereus, 0.88 log10 CFU mL−1 for S. aureus, and 0.73 log10 CFU mL−1 for P. aeruginosa. The results showed a higher reduction in the population of nonpathogenic microorganisms compared to pathogens. The relatively small decrease in the inactivation of bacteria indicates that parameter optimization is necessary to be considered to improve the efficacy of the treatment.

The environmental impact of food packaging, transportation and disposal are escalating, contributing significantly to global solid waste. There's an increasing focus by industry and research on seeking new sustainable solutions for waste valorization. This study investigates the isolation process of biopolymers from legumes (lentil) products and fish (gilthead seabream) waste, with the aim of producing composite films. The developed films were characterized for optical, mechanical and water barrier properties, hydrophobicity (via contact angle measurement), moisture content, water solubility, and biodegradability. Results indicated that lentil and fish protein concentrates may be effectively utilized to fabricate biodegradable packaging materials with adequate moisture barrier properties and excellent optical characteristics. The composite materials from lentil proteins and pectin had higher elongation at break compared to the respective value of the films produced using fish protein and gelatin (44.94 ± 2.81 % and 10.52 ± 1.21 %, respectively). Regarding the composite animal based film, the WVTR and WVP values were measured at 119.50 ± 2.90 g × s−1 × m−2 and 5.04±0.06 × 10−8 × g × m−1 × s-1×Pa−1, respectively. The composite plant based materials had higher WVTR and WVP (139.17 ± 8.01 g × s−1 × m−2 and 7.80 ± 0.91 × 10−8 × g × m−1 × s-1×Pa−1, respectively). The composite film of pectin and concentrated lentil protein exhibited hydrophobic behavior (contact angle 98.63 ± 3.78°), whereas for gelatin and concentrated fish protein films, the contact angle was determined as 57.37 ± 4.00°, indicating hydrophilic behavior. All produced films biodegraded in

Abstract This study presents the valorization of side streams from the sunflower-based biodiesel industry for the production of bio-based and biodegradable food packaging following circular economy principles. Bacterial cellulose (BC) was produced via fermentation in 6 L static tray bioreactors using nutrient-rich supplements derived from the enzymatic hydrolysis of sunflower meal (SFM) combined with crude glycerol as carbon source. Novel biofilms were produced using either matrices of protein isolates extracted from sunflower meal (SFMPI) alone or SFMPI matrices reinforced with nanocellulose biofillers of commercial or bacterial origin. Acid hydrolysis was employed for ex-situ modification of BC to nanostructures (56 nm). The biofilms reinforced with bacterial nanocellulose structures (SFMPI-BNC) showed 64.5% higher tensile strength, 75.5% higher Young’s modulus, 131.5% higher elongation at break, 32.5% lower water solubility and 14.1% lower water vapor permeability than the biofilms produced only with SFMPI. The biofilms were evaluated on fresh strawberries packaging showing that the SFMPI-BNC-based films lead to effective preservation at 10 °C considering microbial growth and physicochemical profile (weight loss, chemical characterization, color, firmness and respiration activity). The SFMPI-BNC-based films could be applied in fresh fruit packaging applications.

Fresh fish is a highly perishable product due to the chemical composition of fish flesh and the high microbial load on fish surface. The natural microflora that is more adopted to low temperatures results also in lower thermal bacterial shock from natural temperature to the preservation temperature range. The development of new fish processing (e.g. high hydrostatic pressure, osmotic dehydration, high-intensity pulsed light) and packaging (e.g. modified atmospheres, active and intelligent packaging) methods or novel combinations of existing technologies is sought by the industry in the pursuit of producing alternative products, achieving shelf life extension, and management and reducing food waste. In 2014, processed fish was among the most active new product categories. The lack of dissemination of validated laboratory results for the seafood industry is one of the major issues preventing the uptake of minimal and nonthermal processing for fresh fish. However, it has been reported that some bacteria become more resistant under stress (e.g. psychrotolerant lactobacilli). At the same time, the application of some processing methods (e.g. thermal processing) may affect significantly the nutritional and sensory profile of the target food product. The application of several “soft hurdles” may reduce the rate of fish deterioration and spoilage caused by microbial growth. The objective of this article is to review the preservative effect of alternative hurdles on fish quality and shelf life, focusing on recent, combined applications. Keywords: Hurdles, Fish, Quality, Safety, Kinetic modelling, Shelf life

The properties of probiotics such as lactic acid bacteria (LAB) have been widely studied over the last decades. In the present study, four different LAB species, namely Lactobacillus gasseri ATCC 33323, Lacticaseibacillus rhamnosus GG ATCC 53103, Levilactobacillus brevis ATCC 8287, and Lactiplantibacillus plantarum ATCC 14917, were investigated in order to determine their ability to survive in the human gut. They were evaluated based on their tolerance to acids, resistance to simulated gastrointestinal conditions, antibiotic resistance, and the identification of genes encoding bacteriocin production. All four tested strains demonstrated high resistance to simulated gastric juice after 3 h, and the viable counts revealed declines in cell concentrations of less than 1 log cycle. L. plantarum showed the highest level of survival in the human gut, with counts of 7.09 log CFU/mL. For the species L. rhamnosus and L. brevis, the values were 6.97 and 6.52, respectively. L. gasseri, after 12 h, showed a 3.96 log cycle drop in viable counts. None of the evaluated strains inhibited resistance to ampicillin, gentamicin, kanamycin, streptomycin, erythromycin, clindamycin, tetracycline, or chloramphenicol. With regard to bacteriocin genes, the Pediocin PA gene was identified in Lactiplantibacillus plantarum ATCC 14917, Lacticaseibacillus rhamnosus GG ATCC 53103, and Lactobacillus gasseri ATCC 33323. The PlnEF gene was detected in Lactiplantibacillus plantarum ATCC 14917 and Lacticaseibacillus rhamnosus GG ATCC 53103. The Brevicin 174A and PlnA genes were not detected in any bacteria. Moreover, the potential antioxidant activity of LAB’s metabolites was evaluated. At the same time, the possible antioxidant activity of metabolites of LAB was first tested using the free radical DDPH• (a, a-Diphenyl-β-Picrylhydrazyl) and then evaluated with regard to their radical scavenging activity and inhibition against peroxyl radical induced DNA scission. All strains showed antioxidant activity; however, the best antioxidant activity was achieved by L. brevis (94.47%) and L. gasseri (91.29%) at 210 min. This study provides a comprehensive approach to the action of these LAB and their use in the food industry.

High pressure is an industrially established food preservation process applied for the minimal processing or cold pasteurization of chilled, fresh, or ready-to-eat products. This study aimed to quantify the effectiveness of high pressure on the inactivation of spoilage microflora and the shelf life extension of European sea bass (Dicentrarchus labrax) fillets. Fish fillets were subjected to mild, high pressure conditions (100–400 MPa; 3–25 °C; 5–10 min) and then stored at 0.0 ± 0.2 °C. Their shelf life was evaluated in terms of their microbiological, physicochemical, and sensorial quality. The results indicated that a shelf life extension of 1–5 d at 0 °C was achieved when pressures of 100 MPa were applied, whereas higher pressures resulted in an up to 5-fold increase in the shelf life of the fillets, depending on the applied pressure and temperature. A high pressure treatment combined with vacuum packaging showed an additional effect on the shelf life extension of the fillets, increasing the shelf life by 4–12 d when compared to aerobically stored products. Moreover, the high pressure treatment prevented lipid oxidation throughout the storage period, indicating no formation of secondary lipid oxidation products. The estimated shelf life of the fish fillets based on their sensorial quality was in accordance with the estimation based on the microbiological data.

Convenient cuts of poultry products are of significant interest, but they are perishable products with a short shelf life. Modified atmosphere packaging (MAP) or the application of active packaging based on edible and biodegradable coatings could extend the shelf life of perishable foods. The aim of the present work was the kinetic modelling of the effect of MAP and active coatings with antimicrobial agents on the microbial growth and shelf life of chicken cuts. Broiler chicken thighs processed with pectin-based (2% w/w aqueous solution) edible coatings enriched with 1% extract of citrus bioflavonoids (flavomix) or 0.5% glucono-δ-lactone were stored under aerobic conditions at 0, 5 and 10 °C. Untreated thighs were also stored aerobically or in MAP (42.7% O2, 18.5% CO2). Quality evaluation was based on the growth of spoilage bacteria (TVC, Pseudomonas spp., Brochothrix thermosphacta), pH, colour, and sensory scoring. The tested quality indices were kinetically modelled and the Arrhenius model was used for the definition of the temperature dependence of the quality loss rates. Pseudomonas spp. dominated spoilage at all packaging and temperature conditions. Microbial growth correlated well with sensory degradation (Ea = 80–100 kJ/mol). Glucono-δ-lactone-enriched edible coatings resulted in 2 days of shelf life extension for chicken thighs at 5 °C. MAP and active, edible coatings with citrus extract showed a similar effect on the quality deterioration rate, and thus the shelf life of chicken cuts. Based on microbial growth, the shelf life was 6–7, 11, and 13 days at 5 °C for the control, EC-glu, MAP, and EC-flav samples, respectively (limit of acceptability = 107 cfu/g for TVC). The results of the study show the potential for using MAP or edible, active coatings to extend the shelf life and improve the commercial value of broiler chicken cuts.

Foodborne listeriosis is one of the most serious and severe foodborne diseases, with a high mortality rate worldwide. Listeria monocytogenes’ (Lm) ability to survive under a diversity of conditions makes it a threat for food safety. Soft and semisoft cheeses are common RTE foods that support survival and growth of Lm due to their high moisture content and favorable pH. The aim of the present study was to assess, after artificial inoculation, the growth potential (Δ) of Lm in vacuum packed RTE soft Greek Anthotyros cheese. Growth potential of Lm was determined according to the new version of “EURL Lm Technical Guidance Document on challenge tests and durability studies for assessing shelf life of ready-to-eat foods related to Lm”. The results of our study revealed that the growth potential of Lm was (Δ) = 4.93 log10 CFU/g, indicating that the specific soft cheese “anthotyros” is a “Ready to eat food able to support growth of Lm and classified in food safety category 1.2 in the (EC) Regulation 2073/2005”. That means that the food business operator (FBO) must comply with the criteria that define that the bacterium must not be detected in 25 g (n = 5, c = 0) at the time of leaving the production plant. Through this study, we try to highlight the need for FBO to conduct relevant research to ensure that the ready-to-eat products which they produce, during their shelf life, do not support the growth of Lm.

The study investigated the effect of active modified atmosphere packaging (20% CO2–60% N2–20% O2) with CO2 emitters (MAP-PAD) and conventional MAP (MAP) on the quality and shelf-life of gilthead seabream fillets during chill storage, while the most appropriate enzymatic Time Temperature Integrators (TTI) were selected for monitoring their shelf-life at isothermal and variable temperature storage conditions (Teff = 4.8 °C). The concentration of CO2 and O2 in the headspace of the package, volatile compounds and of the microbial population were monitored during storage. The kinetic parameters for bacterial growth were estimated at 0–10 °C using the Baranyi growth model. The MAP-PAD samples presented significantly lower microbial growth rates and longer lag phases compared to the MAP samples, leading to significant shelf-life extension: 2 days of extension at 2.5 °C and 5 °C, while 50% extension at variable conditions (Teff = 4.8 °C). CO2 emitters in the package improved the chemical freshness (K-values) and volatile compounds (characterizing freshness). The responses of different enzymatic TTI were modeled as the function of enzyme concentration, temperature and storage time. The activation energy (Ea) ranged from 97 to 148 kJ mol−1, allowing the selection of appropriate TTIs for the shelf-life monitoring of each fish product: LP-150U for the MAP and M-25U for the MAP-PAD samples. The validation experiment at Teff = 4.8 °C confirmed the applicability of Arrhenius-type models, as well as the use of TTIs as effective chill chain management tools during distribution and storage.

The current study aimed to explore the effects of mild processing for shelf-life extension on the raw an-d cooked quality of gilthead seabream fillets stored at 2 °C. Control and Treated (via osmotic dehydration) fillets were sampled at the beginning (D1), middle (D5) and end (D7) of commercial shelf life. The raw quality was evaluated via the quality index method (QIM), microbial measurements and for D1 through tetrad discrimination testing. The cooked quality was evaluated for the same samples via sensory descriptive analyses with a trained panel. The tetrad results indicated similar characteristics between treatments for raw fillets on D1 and a 29% shelf-life extension for Treated fillets vs. the Control ones, defined by Quality Index Method and microbial measurements. The raw quality was reflected in the cooked quality of the tissue, with the Treated fillets exhibiting less intense spoilage-related sensory attributes as well as enhanced or retained freshness-related attributes throughout storage, when compared to the Control ones. A range of treatment induced sensory characteristics, partly associated to Maillard reactions, were developed in the Treated fillets. Overall, the treatment affected positively both the raw and cooked quality of the fillet, showing promising results as a shelf-life extension method for fish fillet preservation.

The objective of the present study was the evaluation of the effect of slurry ice, as an alternative cooling medium during harvesting and transportation, on the quality parameters (e.g., microbiological stability, sensory attributes, physicochemical changes) and shelf life of fish. The effect of seasonal variability of seawater temperature on fish preservation using the tested cooling media was also investigated. Gilthead sea bream (Sparus aurata) was slaughtered and transported in different mixtures of conventional flake ice and slurry ice for 24 h. Three mixtures of ice were tested as T: slaughtered in flake ice and transported in flake ice (control), TC: slaughtered in slurry ice and transported in flake ice, T50: slaughtered and transported in slurry ice 50%–flake ice 50%. Samples were subsequently stored isothermally at 0 °C for shelf-life evaluation. Three independent experiments were performed at three different periods, i.e., January, April, and September, referring to a sea water temperature range of 13.3–26.8 °C. Higher sea water temperatures at catching led to lower microbial growth rates and proteolytic enzyme activities and longer shelf life of refrigerated whole fish. The partial replacement of conventional flake ice with slurry ice improved the quality and extended the shelf life of fish at 0 °C by 2–7 days. The results of the study support that the use of slurry ice may enable better quality maintenance and significant shelf-life extension of whole gilthead sea bream.

Lactic acid bacteria (LAB) play an important role as natural food preservatives. However, the characterization of the variety of their metabolites is limited. The objective of this study was to determine the production of specific metabolites of Lacticaseibacillus rhamnosus, Levilactobacillus brevis and Lactiplantibacillus plantarum by an optimized liquid chromatography with an ultraviolet/diode detection (HPLC-UV/DAD) method and to investigate their potential antimicrobial activity against specific food pathogens. Based on the results of this study, the main metabolites detected in Levilactobacillus brevis were 103.4 μg mL−1 DL-p-Hydroxyphenyllactic acid (OH-PLA) and 2.59 μg mL−1 vanillic acid, while 216.2 μg mL−1 OH-PLA, 19.0 μg mL−1 salicylic acid, 3.7 μg mL−1 vanillic acid, 6.9 μg mL−1 ferulic acid, 4.2 μg mL−1 benzoic acid and 1.4 μg mL−1 4-Hydrocinnamic acid were identified in the Lactiplantibacillus plantarum strain and 147.6 μg mL−1 OH-PLA and 4.9 μg mL−1 ferulic acid were identified in Lacticaseibacillus rhamnosus. This study provides alternative approaches for the molecules involved in the antimicrobial activity of food microorganism fermentation. These molecules may be used as antimicrobial ingredients in the food industry instead of conventional chemical preservatives.

Background: The identification of bacterial species in fermented PDO (protected designation of origin) cheese is important since they contribute significantly to the final organoleptic properties, the ripening process, the shelf life, the safety and the overall quality of cheese. Methods: Ten commercial PDO feta cheeses from two geographic regions of Greece, Epirus and Thessaly, were analyzed by 16S metagenomic analysis. Results: The biodiversity of all the tested feta cheese samples consisted of five phyla, 17 families, 38 genera and 59 bacterial species. The dominant phylum identified was Firmicutes (49% of the species), followed by Proteobacteria (39% of the species), Bacteroidetes (7% of the species), Actinobacteria (4% of the species) and Tenericutes (1% of the species). Streptococcaceae and Lactobacillaceae were the most abundant families, in which starter cultures of lactic acid bacteria (LAB) belonged, but also 21 nonstarter lactic acid bacteria (NSLAB) were identified. Both geographical areas showed a distinctive microbiota fingerprint, which was ultimately overlapped by the application of starter cultures. In the rare biosphere of the feta cheese, Zobellella taiwanensis and Vibrio diazotrophicus, two Gram-negative bacteria which were not previously reported in dairy samples, were identified. Conclusions: The application of high-throughput DNA sequencing may provide a detailed microbial profile of commercial feta cheese produced with pasteurized milk.

Breast milk has been reported as a bacteria source that affects infant gut microbiota development. The present study utilizes a realtime PCR method to identify Lactobacillus and Bifidobacterium spp. in the breast milk of healthy women and attempts to identify factors affecting those human milk bacteria. Breast milk samples—both colostrum and mature milk—of 100 healthy women, were collected in Greece along with data about the demographic factors and nutritional habits of the volunteers. The colostrum samples were found to have higher percentages of either Bifidobacterium or Lactobacillus (76.9% and 48.6%, respectively) compared to the mature milk samples. For younger women, aged from 18 to 29 years, and women from rural areas, bacteria were detected in higher incidence than for older groups and women in urban areas, respectively. Moreover, for high-BMI women, bacteria were detected in lower incidence than for those with normal BMI. Probiotic supplements did not affect the composition of the breast milk-identified bacteria. Various factors such as lactation stage, maternal age, maternal weight, and residential location may contribute to the presence of those species in human milk. RT PCR has significant potential for the microbiological analysis of human milk.

This e research focused on the detection and identification of genetic polymorphisms in exon 7 of the β-casein CSN2 gene in blood samples from Greek Holstein cows and from local breeds of cattle, such as Vrachykeratiki, Katerinis, and Sykias. For this purpose, DNA was isolated from 780 blood samples obtained from Greek Holstein cows, 86 from three local breeds of cattle, namely Brachyceros, Katerinis, and Sykias, and 14 from Greek buffalo. The desired region of exon 7 was amplified by PCR, resulting in 121 and 251 bp products in bovine and buffalo samples. The PCR product was digested with restriction fragment length polymorphism (RFLP) on agarose gels. The restriction enzymes DdeI and TaqI were used. All of the blood samples had the amplified size. The results showed that 74.4% of the Greek Holstein cows had the A2A2 β-casein genotype, the three native breads Vrachykeratiki had 57.7%, and the other two had 100% of the A2A2 β-casein. From the 14 Greek buffalo, 100% had the A2A2 β-casein.

Fresh fish are highly perishable food products and their short shelf-life limits their commercial exploitation and leads to waste, which has a negative impact on aquaculture sustainability. New non-thermal food processing methods, such as high pressure (HP) processing, prolong shelf-life while assuring high food quality. The effect of HP processing (600MPa, 25 °C, 5min) on European sea bass (Dicentrarchus labrax) fillet quality and shelf life was investigated. The data presented comprises microbiome and proteome profiles of control and HP-processed sea bass fillets from 1 to 67 days of isothermal storage at 2 °C. Bacterial diversity was analysed by Illumina high-throughput sequencing of the 16S rRNA gene in pooled DNAs from control or HP-processed fillets after 1, 11 or 67 days and the raw reads were deposited in the NCBI-SRA database with accession number PRJNA517618. Yeast and fungi diversity were analysed by high-throughput sequencing of the internal transcribed spacer (ITS) region for control and HP-processed fillets at the end of storage (11 or 67 days, respectively) and have the SRA accession number PRJNA517779. Quantitative label-free proteomics profiles were analysed by SWATH-MS (Sequential Windowed data independent Acquisition of the Total High-resolution-Mass Spectra) in myofibrillar or sarcoplasmic enriched protein extracts pooled for control or HP-processed fillets after 1, 11 and 67 days of storage. Proteome data was deposited in the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifiers PXD012737. These data support the findings reported in the associated manuscript “High pressure processing of European sea bass (Dicentrarchus labrax) fillets and tools for flesh quality and shelf life monitoring”, Tsironi et al., 2019, JFE 262:83–91, doi.org/10.1016/j.jfoodeng.2019.05.010. Keywords: Colour and texture, European sea bass, Fish fillet, High pressure, 16S rRNA microbiome, Quantitative proteomics

The aim of the study was the evaluation and mathematical modeling of the effect of active modified atmosphere packaging (MAP), by the incorporation of CO2 emitters in the package, on the microbial stability and shelf life of gutted sea bass during refrigerated storage. Gutted sea bass samples were packaged in modified atmosphere (50% CO2−40% N2−10% O2) with and without CO2 emitters (ACT-MAP, MAP) (gas/product volume ratio 3:1) and stored at isothermal conditions: 0 °C, 5 °C, and 10 °C. The gas concentration in the package headspace (%CO2, %O2) and microbial growth (total viable count, TVC, Pseudomonas spp., Enterobacteriaceae spp., lactic acid bacteria) were monitored during storage. The microbial growth was modeled using the Baranyi growth model, and the kinetic parameters (microbial growth rate, lag phase) were estimated at the tested temperature and packaging conditions. The results showed that the ACT-MAP samples presented significantly lower microbial growth compared to the MAP samples. The growth rate of the total viable count at 0 °C was 0.175 and 0.138 d−1 for the MAP and ACT-MAP sea bass, respectively (p < 0.05). The shelf life of the MAP sea bass at 0−10 °C (based on a final TVC value: 7 log CFU g−1) was extended 4−7 days with the addition of a CO2 emitter in the package. The CO2 concentration in the ACT-MAP samples was stabilized at approximately 60%, while the CO2 in the MAP samples was approximately 40% at the end of the shelf life.

The objective of this work is the comparative study of different osmotic treatments at 37 °C on the quality and shelf life of chilled sea bass fillets. Fish fillets were treated using osmotic solutions consisting of oligofructose (40%–50%–60%) and 5% NaCl with (BP/OT) and without (OT) former antioxidant enrichment by using Rosa damascena distillation by-products. Water activity decreased to approximately 0.95 after 330 minutes of osmotic treatment. Untreated and osmotically treated fish fillets (BP/OT) and (OT) were subsequently stored at 5 °C and their quality was evaluated based on microbial growth and lipid oxidation. Osmotic treatment extended significantly the shelf life of fish in terms of microbial growth; however, it also accelerated its lipid oxidation. The impregnation of Rosa damascena phenolics not only counterbalanced this negative effect, but led to a more than four-fold increase of the shelf life of sea bass, as compared to the untreated samples.

Application of an optimized cold chain management system for frozen products can be assisted by monitoring with Time Temperature Integrators (TTI). TTI are smart labels that cumulatively show the product history in an easily measurable, time-temperature dependent change. In the IQ-Freshlabel European project enzymatic and photochromic TTI were developed and tested for frozen products. Further to the technical objectives, training activities were implemented to provide information and training to the staff of Small and Medium-sized Enterprises (SMEs) regarding the properties of the developed TTI and their utilization within food packaging, transport, storage and sale. In total, more than 276 European companies and consumers representing the frozen food industry, the packaging industry and food business operators were successfully trained. The objective of the present article is to describe a general methodology for frozen food shelf life testing and modelling, and the selection of appropriate TTI for specific foods. This document serves as a technical manual for SMEs, including a case study for frozen shrimp and application of enzymatic and photochromic TTI, aiming to build their capacities to understand and use TTI for frozen food products. The value of systematic modelling of the food quality kinetics as well as the response of the TTI in building an effective chill chain management system is also demonstrated. The TTI response study allows a reliable optimization and selection of TTI to be correlated to the target food product for which accurate information on temperature dependence is available.