Peroxidase actvity, its isozymes and deterioration of pearl millet [Pennisetum glaucum (L.) R. BR.] flour during storage

Development of off odour and flavour is an old and unresolved problem associated with pearl millet flour during storage and is the major hindrance for their consumer acceptability. In this study role of peroxidase, lipids and phenolics in deterioration of quality of pearl millet in control and stored flour of high (HHB 94) and low (ICMA 94222 x 78/71) rancid genotype was determined. Fat content, fat acidity, free fatty acids, total phenols, C-glycosylflavones content and peroxidase activity of HHB 94 were higher than that of ICMA 94222 x 78/71. Storage of flour for 8 days of these two genotypes showed significant increase in fat acidity and free fatty acids. Storage had no effect on C-glycosylflavones content whereas peroxidase activity reduced significantly with storage time. Isozyme profile showed that pearl millet grains had 3 isozymes of peroxidase and banding pattern was similar in both HHB 94 and ICMA 94222 x 78/71. While banding intensity represented that ICMA 94222 x 78/711 had lesser peroxidase activity as compared to HHB 94. The result suggested that peroxidase activity, fat acidity and free fatty acid value were usually correlated