Effects of fermentation on proximate composition, mineral profile and antinutrients of tamarind (Tamarindus indica L.) seed in the production of daddawa-type condiment

Tamarind seed is an underutilized legume which can potentially be used as a food condiment. In this study, tamarind seed was fermented using the conventional traditional method of iru (daddawa) production. Samples withdrawn at intervals of 24 h were tested for proximate composition, antinutrients, mineral profile, and other physicochemical properties using standard methods. Protein, fat and carbohydrates were the major nutrients in the tamarind seed before and after fermentation. Phosphorus was the major mineral element of the raw (0.97 mg/100 g) and fermented (0.96–1.06 mg/100 g) tamarind seed. Fermentation substantially decreased the phytic acid contents (approx. 50%), tannin contents (approx. 75%) and trypsin inhibitor activity (approx. 86%). Bacillus subtilis, Bacillus licheniformis, and Bacillus pumilus were isolated as the organisms fermenting the tamarind seed. Fermented tamarind seed can be potentially used as a condiment for seasoning foods. However, future studies such as consumer acceptability are required to determine the acceptability of the fermented tamarind seed by potential consumers.