Microbiological safety and microbiota of Kapi, Thai traditional fermented shrimp paste, from different sources

Abstract

Kapi is traditional Thai shrimp paste and is usually used as a seasoning. Traditional fermented foods are considered safe due to their long-standing consumption history, despite not having been evaluated for hygiene and microbiologically safety. Since Kapi is produced by natural fermentation, the microbiota differs depending on the raw material and production method. To control the quality of Kapi to a certain level, it is important to understand the microbiota of the product. In the present study, 27 Kapi samples purchased from wet markets and supermarkets were evaluated for microbiological safety and their microbiota was analyzed using 16S rRNA gene amplicon sequencing analysis. From the physicochemical analysis, the Kapi sample purchased at the wet market had a larger variation in pH and sodium chloride. Moreover, Kapi purchased from the wet market had a higher detection rate of E. coli, coliforms, and Bacillus group than those purchased from the supermarket. Salmonella, Listeria sp., and Vibrio sp. were not detected in any sample. The results of 16S rRNA gene amplicon sequencing analysis revealed that the microbiota differed for each sample regardless of the place of purchase, with Lentibacillus sp., Tetragenococcus sp., Salinicoccus sp., and Alkalibacillus sp. as the predominant groups.