Millet processing to fermented drinks: Evaluating changes in nutritional attributes, mineral accessibility, amino acid profile, and sensorial acceptability

Abstract

Fermented drinks form an integral part of our dietary culture. Traditional processing methods can provide a framework that can be used to develop these drinks. In this study, a fermented Indian millet drink Koozh has been studied. Traditionally it is prepared from finger or pearl millet, however in this study three other minor millets varieties i.e. kodo, barnyard and little were also explored to prepare it. Two-way repeated measure ANOVA indicate that millet type, processing and their interaction plays a major role in determining the overall composition of the final drink. Overall fermented millet drinks had high nutritional value, with reduced phytate content (45–93 %). FTIR analysis of the methanolic extract of the drinks showed many functional peaks and the extract was further used to determine the polyphenol content and antioxidant activity (FRAP and DPPH). The millet drinks had high Mg, Fe and Zn content along with essential amino acids particularly isoleucine (16.15–16.85 g/100 free amino acid (FAA)). Mineral analysis reveals that these drinks can be a good source of iron containing approximately 0.15–0.56 mg/100g bio-accessible iron. Principal component analysis (PCA) was employed to identify the key variables contributing to the differences among different millet drinks. Sensorial analysis showed high acceptability among consumers, with barnyard and little millet drinks receiving the highest overall scores. The results from this study indicate that fermented millet drink offer a unique mix of nutritional and functional benefits that needs to be further explored.