Effect of Starter Culture on Volatile Organic Compounds of Bambara Groundnut Condiment

Abstract:

Bambara nut (Vigna subterranea) is one of the underutilized legumes in Africa that can be used to replace animal protein thereby combating malnutrition and shortage of food in Africa. In this study, Bambara nut condiments were produced by spontaneous and laboratory fermentation using starter cultures of Bacillus subtilis and Bacillus llicheniformis in combination. The bacteria associated with both fermentations were Streptococcus spp., Staphylococcus saprophyticus, Bacillus subtilis and Bacillus licheniformis. The mean heterotrophic bacterial counts were 3.1x106 cfug-1 and 3.8x106 cfug-1 for spontaneously and laboratory fermented condiments. Aroma and flavour volatile organic compounds were also determined using GC-MS analysis. The GC-MS analysis revealed 25 compounds that included 6 acids, 1 alcohol, 1 aldehyde, 6 aliphatics/ aromatics, 1 alkyl halide, 2 amines, 3 hydrocarbons, 2 ketones and 2 nitriles. These compounds play role in the flavour and aroma of Bambara nut condiment (daddawa). This study suggests that this condiment (daddawa) could be a good and cheap source of protein and a substitute to monosodium glutamate-based salts and can have health benefits due to the presence of probiotic bacteria.