Factors affecting bacterial community dynamics and volatile metabolite profiles of Thai traditional salt fermented fish

Abstract

Bacterial diversity of the Thai traditional salt fermented fish with roasted rice bran (Pla-ra) was investigated using classical and molecular approaches. Bacterial population of Pla-ra ranged from 102–106 in solid-state (SSF) and 106–109 CFU/g in submerged (SMF) fermentation types. Halanaerobium spp. and Lentibacillus spp. were the main genera particularly detected when rRNA analysis was applied. Tetragenococcus halophillus were dominant during the final stage in sea salt-recipe samples while Bacillus spp. were found in those rock salt recipes. In contrast, cultural plating demonstrated that Bacillus spp., generally B. amyloliquefaciens, were the dominant genera. In addition, B. pumilus, B. autrophaeus, B.subtilis and B. velezensis shown some relations with rock salt-recipe samples. The main volatile metabolites in all samples were butanoic acid and its derivatives. Key factors affected bacterial profiles and volatile compounds of salt fermented fish were type of salt, addition of roasted rice bran, and fermenting conditions.

Transforming the fermented fish landscape: Microbiota enable novel, safe, flavorful, and healthy products for modern consumers

“…Hexanal, 1-octene-3-ol, linalool, and limonene were the main flavor composition in the fermented fish product in China (Shen et al, 2021). In the fermented fish (pla-ra) from Thailand, butanoic acid and its derivatives were identified as the main volatile compounds, and the gamma-Glu-Val-Gly was contributed to the taste (Det-Udom et al, 2022;Phewpan et al, 2020b). And the characteristic flavor of funazushi (Japan) was derived from ethyl acetate, ethyl lactate, ethyl alcohol, and 2-phenylethyl alcohol (Kubo et al, 2008).…”

“…According to the type of auxiliary materials, fermented fish products can be divided into dry‐cured products, rice‐based cured products, and vinegar‐based cured products (Zang et al., 2020b). Fermented fish products can also be grouped according to their morphologies: Fermented fish bodies, such as the narezushi from Japan (Nishida et al., 2021), hákarl from Iceland (Osimani et al., 2019), myeolchi‐jeot from Korea (Jae‐Hyung et al., 2005), pla‐ra from Thailand (Det‐Udom et al., 2023), jaadi from Sri Lanka (Ubhayasekera et al., 2012), and meixiangyu from China (Chen et al., 2021); Fermented surimi, such as som‐fug from Thailand (Riebroya et al., 2008), and funasushi from Japan; Fermented fish sauce, such as yulu from China and momoni in from Ghana (Wang et al., 2019; Zang et al., 2020b). The flavor profiles of these fermented fish products differ greatly, due to the large variations in their raw materials, microorganisms, processing steps, production, and environmental conditions, which reflect exactly the regional characteristics, and cultural behaviors and habits.…”

Dynamic Changes in Physicochemical and Microbiological Qualities of Coconut Water during Postharvest Storage under Different Conditions

“…Metabolite profiles in term of volatile compounds were detected by GC/MS following a protocol used in our previous work [19]. SPME fiber (50/30 µm DVB/CAR/PDMS, Supelco, Bellefonte, PA) was used to extract volatile compounds, while detection was achieved by gas chromatography-mass spectrometry (Agilent 7890 A GC-7000 Mass Triple Quad) equipped with a capillary column (DB-WAX, 60 m × 0.25 mm × 0.25 µm, J&W Scientific, Santa Clara, CA, USA) and a quadrupole mass detector.…”