The influences of fish infusion broth on the biogenic amines formation by lactic acid bacteria

PubMedID: 24294229The influences of fish infusion decarboxylase broth (IDB) on biogenic amines (BA) formation by lactic acid bacteria (LAB) were investigated. BA productions by single LAB strains were tested in five different fish (anchovy, mackerel, white shark, sardine and gilthead seabream) IDB. The result of the study showed that significant differences in ammonia (AMN) and BA production were observed among the LAB strains in fish IDB (p < 0.05). The highest AMN and TMA production by LAB strains were observed for white shark IDB. The all tested bacteria had decarboxylation activity in fish IDB. The uppermost accumulated amines by LAB strains were tyramine (TYM), dopamine, serotonin and spermidine. The maximum histamine production was observed in sardine (101.69 mg/L) and mackerel (100.84 mg/L) IDB by Leuconostoc mesenteroides subsp. cremoris and Pediococcus acidophilus, respectively. Lactobacillus delbrueckii subsp. lactis and Pediococcus acidophilus had a high TYM producing capability (2943 mg/L and 1157 mg/L) in sardine IDB. © 2013, Sociedade Brasileira de Microbiologia

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°C

The 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°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. © 2019 Wiley Periodicals, Inc