Selection of γ-aminobutyric acid-producing lactic acid bacteria and their potential as probiotics for use as starter cultures in Thai fermented sausages (Nham)

摘要

To produce a novel product of Thai fermented meats, such as healthy Nham, 602 lactic acid bacteria were isolated from fermented foods and fourteen isolates that produced high amounts of γ-aminobutyric acid (GABA) were also tested for inhibiting the seven foodborne bacteria. Four selected isolates produced GABA in the range of 7339-9060 mg L~(-1) (NH2 < NH102 < NH116 < HN8) and their culture filtrates with a pH of 3.8, except 4.2 for NH2 inhibited all target organisms. Selected strains were investigated for their physiological and functional properties of probiotics in vitro. Strain NH102 survived best in the gastrointestinal tract with only a one log cell decrease over 4 h, whereas strain NH116 was the best cholesterol removal (43%). None showed any haemolysis and all hydrolased bile salts. Strain NH2 was identified as Lactobacillus namurensis and all the others were Pediococcus pentosaceus. Strains HN8 and NH2 were potential starters for fermenting meats.