The effectiveness of garlic extracts on biogenic amine formation by foodborne pathogens and fish spoilage bacteria

Impacts of aqueous and ethanolic extracts of garlic were investigated in suppressing bacterial growth and biogenic amine (BA) formation by selected foodborne pathogens (Candida albicans, Salmonella paratyphi A, Escherichia coli and Staphylococcus aureus) and fish spoilage bacteria (Enterococcus faecalis, Photobacterium damselae and Pseudomonas luteola). The spread-plate method was used to monitor bacterial growth in histidine decarboxylase broth (HDB), whereas the rapid high-performance liquid chromatographic (HPLC) method was used for BA analysis. Bacterial growth and their ammonia and BA production were monitored using HDB. The results showed that bacterial growth on HDB was in the range from 9.13, for P. luteola, to 9.54 log CFU (colony-forming units) mL−1, for S. aureus and C. albicans. The presence of garlic extracts in HDB resulted considerably in lowering bacterial growth and BA formation (P < 0.05). The highest inhibitory activities of ethanolic and water garlic extracts were obtained for Gram-positive S. aureus with 1.4 and 1.5 logarithmic reduction on bacterial growth, followed by Gram-negative Salmonella Paratyphi A and E. coli. Application of garlic extracts, mainly ethanolic ones, showed a significant inhibitory effect on bacterial ammonia production, with 4-100-fold lower ammonia accumulation (P < 0.05). Bacteria produced all tested BAs, mainly dopamine, agmatine and tryptamine. The highest levels of histamine and tyramine (61.99 and 36.45 mg L−1) were produced by S. aureus. In the presence of aqueous or ethanolic garlic extracts, putrescine production by E. faecalis was around 110-fold lower than that of the control group. Results revealed that both garlic extracts are potent antimicrobials that can control the growth of foodborne pathogens and their harmful BA formation.info:eu-repo/semantics/publishedVersio

Physical, chemical, and sensory properties of water kefir produced from Aronia melanocarpa juice and pomace

Water kefir is widely consumed all over the world due to its potential health benefits. The aim of this current study was to compare non-fermented juice and fermented beverage of water kefir produced from Aronia melanocarpa juice and pomace in terms of chemical, physical and sensory quality as well as valorisation of pomace in the production of water kefir. When compared to water kefir made with aronia juice, less reduction in total phenolic content (TPC), total flavonoid content (TFC) and total anthocyanin content (TAC) was observed in samples made with aronia pomace during the fermentation process. Similarly, greater antioxidant activity was demonstrated in water kefir made with aronia pomace than juice. Based on sensory evaluation, no difference was found in overall acceptability, taste, aroma/odor, and turbidity of water kefir made with aronia pomace before and after fermentation. Results indicated that aronia pomace has potential in water kefir productio

Physical, chemical, and sensory properties of water kefir produced from Aronia melanocarpa juice and pomace

Water kefir is widely consumed all over the world due to its potential health benefits. The aim of this current study was to compare non-fermented juice and fermented beverage of water kefir produced from Aronia melanocarpa juice and pomace in terms of chemical, physical and sensory quality as well as valorisation of pomace in the production of water kefir. When compared to water kefir made with aronia juice, less reduction in total phenolic content (TPC), total flavonoid content (TFC) and total anthocyanin content (TAC) was observed in samples made with aronia pomace during the fermentation process. Similarly, greater antioxidant activity was demonstrated in water kefir made with aronia pomace than juice. Based on sensory evaluation, no difference was found in overall acceptability, taste, aroma/odor, and turbidity of water kefir made with aronia pomace before and after fermentation. Results indicated that aronia pomace has potential in water kefir production

Nucleotide degradation and biogenic amine formation of wild white grouper (Epinephelus aeneus) stored in ice and at chill temperature (4 degrees C)

WOS: 000253620200018PubMed ID: 26065755Sensory (cooked and uncooked), chemical (proximate composition, TVB-N, nucleotide degradation products and biogenic amines) and microbiological quality (TVC and total coliform) changes were investigated during storage of ungutted white grouper kept in ice and at chill temperature (4 degrees C). According to the sensory assessment, the shelf life of white grouper was 16 days in ice and 4 days for fish stored at chill temperature. TVB-N values increased with storage time. Amines found in white grouper stored in ice were TMA, putrescine, cadaverine, 2-phenylethylamine, dopamine, agmatine, tryptamine and serotonin. Histamine, spermine, spermidine were never detected with either storage condition. The acceptability limit in terms of microbial count was exceeded at 8 days in ice and at 4 days for fish stored at chill temperature. Total coliform count was 2.8 log(10) cfu/ml at 1 day and reached 10(5) cfu/ml for both storage conditions. (c) 2007 Elsevier Ltd. All rights reserved

Simple Extraction and Rapid HPLC Method for Tocopherol Analysis in Marine and Fresh-water Fish Species

WOS: 000298511500021A rapid high-performance liquid chromatographic (HPLC) method with simple extraction procedure for the determination of tocopherols in seafood was developed. A continuous isocratic elution system was used for the analysis with a mixture of acetonitrile and methanol. Tocopherols were identified by comparison of retention times and peak area values with standard of alpha-, beta-, gamma- and delta-tocopherols. The HPLC technique used showed good performance parameters (linearity r(2) = 0.9999, and relative standard deviation (RSD) <= 12.38%). The total recoveries for each tocopherol were 99.7, 99.9, 99.8 and 99.7% for alpha, beta, gamma- and delta, respectively. This method was then applied to freshwater and seawater fish species to detect their tocopherol contents. Significant differences (P < 0.05) were observed in the content of tocopherol among fish species. The highest content was obtained from shrimp (81.3 mg/kg), while the lowest was found for whiting (9.8 mg/kg)

The effects of nanoemulsions on the fatty acid profiles of sea bass fillets during storage at 2 +/- 2 degrees C

WOS: 000456094300001The effect of nanoemulsions prepared from commercial oils on the fatty acid profiles of cold-stored sea bass fillets was investigated. The sea bass fillets were treated with nanoemulsions prepared from sunflower, canola, corn, olive, soybean, and hazelnut oils (14% of the total emulsion). Results of fatty acid analyses showed that the main fatty acids found in all groups were determined to be miristic acid, palmitic acid, stearic acid, palmitoleic acid, oleic acid, linoleic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). At the end of storage, the control group (24.05%) had the highest SFA content, while the lowest SFA among the nanoemulsion treatment groups was observed in the olive group (21.97%) followed by sunflower group (22.78%). The oleic (C18:1n9) and palmitoleic acids (C16:1) from monounsaturated fatty acids (MUFA) varied between 30.45-23.82% and 4.92-3.42% during storage period. Among all polyunsaturated fatty acids (PUFA), linoleic acid, EPA and DHA were predominant fatty acids. EPA and DHA ranged from 4.73 to 2.81% and 8.09 to 4.06%, respectively. While the lowest PUFA content was observed in the control group, the highest value was determined in the soybean group (26.41%), followed by olive (24.48%) and canola (24.46%) at the end of storage. The results showed that the nanoemulsion application delayed lipid oxidation. Application of nanoemulsion compared to control group maintained the PUFA content of fish and can be used as a preservative for fish.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [TOVAG-113O379]The authors wish to thank the Scientific and Technological Research Council of Turkey (TUBITAK) for the financial support (TOVAG-113O379) and the authors also gratefully acknowledge infrastructure support provided by Cukurova University

Seasonal proximate and fatty acid variations of some seaweeds from the northeastern Mediterranean coast

Abstract The seasonal nutritional value of red (Jania rubens, Laurencia papillosa, Spyridia filamentosa and Dasya rigidula) and brown macroalgae (Padina pavonia and Stypopodium schimperi) was evaluated as a dietary supplement for human and animal nutrition based on proximate and fatty acid profiles. The protein content varied from 0.80% (L. papillosa) to 3.41% (J. rubens) of wet weight with the highest values in winter. The highest lipid levels were recorded in S. schimperi (2.03% in spring, 2.16% in summer), the lowest in S. filamentosa (0.08% in spring). The ash content of J. rubens (46.11-51.63%) was significantly higher than that of the other species (2.28-16.57%). Analysis of the fatty acid composition showed that these seaweed species are very rich in n-3 fatty acids. The complete text of the paper is available at http://www.iopan.gda.pl/oceanologia/ 376 S. Polat, Y. Ozogul DHA -docosahexaenoic acid, EPA -eicosapentaenoic acid, FA -fatty acid, EFAs -essential fatty acids, FAME -fatty acid methyl ester, FID -flame ionization detector, GC -gas chromatography

Technological factors affecting biogenic amine content in foods: a review

Biogenic amines (BAs) are molecules which can be present in foods and, due to their toxicity, can cause adverse effects on the consumers. BAs are generally produced by microbial decarboxylation of amino acids in food products. The most significant BAs occurring in foods are histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine and agmatine. The importance of preventing the excessive accumulation of BAs in food is related to their impact on human health and food quality. Quality criteria in connection with the presence of BAs in food and food products are necessary from a toxicological point of view. This is particularly important in fermented foods in which the massive microbial proliferation required for obtaining specific products is often relater with BA accumulation. In this review, up-to-date information and recent discoveries about technological factors affecting biogenic amine content in foods are reviewed. Specifically, BA forming-microorganism and decarboxylation activity, genetic and metabolic organization of decarboxylases, risk associated to BAs (histamine, tyramine toxicity and other BAs), environmental factors influencing BA formation (temperature, salt concentration, pH). In addition, the technological factors for controlling BA production (use of starter culture, technological additives, effects of packaging, other non-thermal treatments, metabolising BA by microorganisms, effects of pressure treatments on BA formation and antimicrobial substances) are addressed

Recent developments in valorisation of bioactive ingredients in discard/seafood processing by-products

International audienceBackground: Seafood processing activity causes production of considerable amount of waste/by-products and discards, resulting in negative economic and environmental impacts. Management of sustainable utilisation of seafood resources is essential to avoid environmental problems and provide resource sustainability. Scope and approach: Fishery discards and seafood by-products are rich in bioactive compounds, including omega3 long-chain polyunsaturated fatty acids, amino acids, peptides, enzymes, gelatine, collagen, chitin, vitamins, polyphenolic constituents, carotenoids etc. Fish discards are also regarded as a good and cheap material for biodiesel production. These high value added compounds have potential applications in many industrial sectors including food, nutraceuticals, pharmacology, medical, agriculture, depending on their functional and structural characteristics. This review will provide a comprehensive information on recent approaches for valorisation of bioactive compounds derived from discards and seafood by products. Key findings and conclusions: Many studies on the bioactive compounds derived from fishery discards and processing by-products were carried out in terms of nutritional and functional properties. Further studies on bioavailability of nutrients, yield, physicochemical properties, interaction with other ingredients, together with innovative approaches for extraction methods and legislation and safety issues should be considere

The effects of edible oil nanoemulsions on the chemical, sensory, and microbiological changes of vacuum packed and refrigerated sea bass fillets during storage period at 2 +/- 2 degrees C

WOS: 000494414700001The quality of vacuum packed sea bass fillets treated with nanoemulsions based on commercial oils (hazelnut oil, corn oil, canola oil, soybean oil, olive oil, and sunflower oil) at 2 +/- 2 degrees C was evaluated by sensory, chemical (thiobarbituric acid reactive substances, peroxide value, total volatile basic nitrogen, and free fatty acids), and microbiological (total psychrophilic bacteria, total Enterobacteriaceae counts, total mesophilic aerobic bacteria, and total lactic acid bacteria) methods. The chemical parameters of fillets treated with the nanoemulsions presented lower values than those of the control group. Microbiological assessment correlated with sensory analyses. The use of nanoemulsions extended shelf life of fish, 4 days for canola, corn, soybean, and hazelnut oils and 2 days for olive and sunflower treatment groups. The quality of chemical, sensory, and microbiological parameters of sea bass fillets was increased with the application of oil nanoemulsions as well as their shelf life. Practical applications Nanomulsions have been paid attention since they are known as ideal carrier for the delivery of lipophilic substances because of small particle size, the ease of preparation, high bioavailability, and long-term stability. They are also proven to be self-preserving antimicrobials due to the bound water in their structure and restricted available water to microorganisms. Nanoemulsion has been shown to extend the shelf life of different species of fish by lowering the value of biochemical parameters and also inhibiting microbial growth.Turkiye Bilimsel ve Teknolojik Arastirma KurumuTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [TOVAG-113O379]Turkiye Bilimsel ve Teknolojik Arastirma Kurumu, Grant/Award Number: TOVAG-113O37