Reduction of histamine in fish sauces by rice bran nuka

Regulation of microbial metabolism on the formation of characteristic flavor and quality formation in the traditional fish sauce during fermentation: a review

Fish sauce is a special flavored condiment formed by traditional fermentation of low-value fish in coastal areas, which are consumed and produced in many parts of the world, especially in Southeast Asia. In the process of fish sauce fermentation, the diversity of microbial flora and the complex metabolic reactions of microorganisms, especially lipid oxidation, carbohydrate fermentation and protein degradation, are accompanied by the formation of flavor substances. However, the precise reaction of microorganisms during the fersmentation process is difficult to accurately control in modern industrial production, which leads to the loss of traditional characteristic flavors in fermented fish sauces. This paper reviews the manufacturing processes, core microorganisms, metabolic characteristics and flavor formation mechanisms of fermented fish sauces at home and abroad. Various methods have been utilized to analyze and characterize the composition and function of microorganisms. Additionally, the potential safety issues of fermented fish sauces and their health benefits are also reviewed. Furthermore, some future directions and prospects of fermented fish sauces are also reviewed in this paper. By comprehensive understanding of this review, it is expected to address the challenges in the modern production of fish sauce thereby expanding its application in food or diet.

Contribution of Microorganisms to Biogenic Amine Accumulation during Fish Sauce Fermentation and Screening of Novel Starters

In this study, high-throughput sequencing and culture-dependent and HPLC methods were used to investigate the contribution and regulation of biogenic amines (BAs) by dominant microorganisms during fish sauce fermentation. The results showed that the microbial composition constantly changed with the fermentation of fish sauce. Tetragenococcus (40.65%), Lentibacillus (9.23%), Vagococcus (2.20%), Psychrobacter (1.80%), Pseudomonas (0.98%), Halomonas (0.94%) and Staphylococcus (0.16%) were the dominant microflora in fish sauce. The content of BAs gradually increased as the fermentation progressed. After 12 months of fermentation, the histamine content (55.59 mg/kg) exceeded the toxic dose recommended by the Food and Drug Administration (FDA). Correlation analysis showed that dominant microorganisms have a great contribution to the accumulation of BAs. By analyzing the BA production capacity of dominant isolates, the accumulation of BAs in fish sauce might be promoted by Tetragenococcus and Halomonas. Moreover, four strains with high BA reduction ability were screened out of 44 low BA-producing dominant strains, and their influence on BA accumulation in fermented foods was determined. Results demonstrated that Staphylococcus nepalensis 5-5 and Staphylococcus xylosus JCM 2418 might be the potential starters for BA control. The present study provided a new idea for the control of BAs in fermented foods.

Inhibitory Effects of Spices on Biogenic Amine Accumulation during Fish Sauce Fermentation

The presence of high levels of biogenic amines is detrimental to the quality and safety of fish sauce. This study investigated the effects of ethanol extracts of spices, including garlic, ginger, cinnamon, and star anise extracts, in reducing the accumulation of biogenic amines during fish sauce fermentation. The concentrations of biogenic amines, which include histamine, putrescine, tyramine, and spermidine, all increased during fish sauce fermentation. When compared with the samples without spices, the garlic and star anise extracts significantly reduced these increases. The greatest inhibitory effect was observed for the garlic ethanolic extracts. When compared with controls, the histamine, putrescine, tyramine, and spermidine contents and the overall biogenic amine levels of the garlic extract-treated samples were reduced by 30.49%, 17.65%, 26.03%, 37.20%, and 27.17%, respectively. The garlic, cinnamon, and star anise extracts showed significant inhibitory effects on aerobic bacteria counts. Furthermore, the garlic and star anise extracts showed antimicrobial activity against amine producers. These findings may be helpful for enhancing the safety of fish sauce.