Lactobacillus plantarum and natural fermentation-mediated biotransformation of flavor and aromatic compounds in horse gram sprouts

Bio-transformed volatile compounds in horse gram sprouts, Lactobacillus plantarum NRRL B-4496 and Lactobacillus plantarum NCDO 1193 mediated as well as naturally fermented horse gram sprouts were analyzed using gas chromatography-mass spectrometry coupled with headspace solid-phase micro extraction. A total of 36 compounds, including acids, alcohols, aldehydes, esters, ketones, sulfur containing compounds were identified in sprouts fermented for 1, 2, 3, 4 and 5 days by mass spectral data, Kovats indices and comparing authentic standards. Fermentation-mediated volatile metabolites such as acetic acid, eugenol, benzyl alcohol (benzene methanol), acetoin, 2, 3-butanediol and ethyl palmitate were found to be the prime contributors to the sensory attributes of fermented samples. As the contents of alcohols, ketones, esters and phenols increased during fermentation, some aldehydes significantly decreased. For the first time, eugenol was detected in fermentation of horse gram, paving the way for new bioprocessing strategy for production of health beneficial aroma compound. Therefore, fermentation of horse gram sprouts enhances bio-transformed volatile composition derived from primary metabolites which has relevance for improving value-added flavor and health benefits from short chain fatty acids while integrating potential probiotic benefits.