Use of Lactococcus lactis to enrich sourdough bread with γ-aminobutyric acid

Fried sourdough bread (bhatura) with an elevated amount of gamma-aminobutyric acid (GABA) was produced using lactic acid bacteria (LAB). The LAB starter was screened and isolated from pickled yam showing highest GABA content and was identified as Lactococcus lactis subsp. lactis. The maximum GABA production in de Man Rogosa Sharpe (MRS) media supplemented with monosodium glutamate (MSG) was 110 mg/100 ml at pH 5, and 1-3% NaCl did not change the production of GABA significantly (p > 0.05). When MSG was replaced with Vigna mungo in sourdough, the amount of GABA for bhatura was 226.22mg/100 g representing about 10-fold increase. A sensory evaluation resulted as the overall general acceptability of bhatura to be 4.91 +/- 0.03 on a five-point hedonic scale. Thus, the results indicated the potential of L. lactis as a LAB starter for the production of GABA-enriched bhatura. Although other physiological effects can be expected in the product, animal and clinical studies are mandatory prior to application of this food.