THE IMPACT OF SPROUTING ON AMYLASE ACTIVITIES AND FUNCTIONAL PROPERTIES OF TEN (10) NATIVE RICE VARIETIES IN NIGERIA

This research aimed to assess the impact of sprouting on the activity of amylases and the functional attributes of ten distinct FARO rice varieties. The chosen FARO rice specimens, namely FARO 15, 16, 20, 22, 30, 45, 47, 55, 61, and 62, were subjected to a twelve-day sprouting process in accordance with established protocols. The objective was to investigate amylase activities and their associated functional characteristics. Over the course of sprouting, the alpha, beta, and glucoamylase activities of the FARO rice samples were quantified daily. Correlation coefficients and linear regression equations were formulated to establish connections between the amylose content of FARO rice samples and their functional attributes. The findings indicated that the α-amylase activity of FARO rice samples exhibited a steady increase from the 3rd to the 10th day of sprouting. The peak α-amylase activity was observed on the 5th and 6th days, ranging from 46.18 x 10^-3 to 50.17 x 10^-3 U/ml. Likewise, β-amylase activity showed an escalating trend from the 3rd to the 8th day of sprouting. The highest β-amylase activity occurred on the 5th and 6th days, within the range of 44.01 x 10^-3 to 46.07 x 10^-3 U/ml. Most of the FARO rice samples displayed increased glucoamylase activity from the 3rd to the 7th day of sprouting, peaking at 100 x 10^-3 U/ml on the 5th day. The results further unveiled that prolonged sprouting led to a decrease in amylose content, swelling capacity, and gelling temperature, while solubility and gelling time exhibited an increase. Significant positive correlations were established between the amylose content of FARO rice samples and their swelling capacity and gelling temperature, while notable negative correlations were noted with solubility and gelling time for most samples. This study underscores the cost-effective and efficient potential of sprouting in enhancing amylase yields and refining the functional properties of FARO rice varieties, thereby enhancing their utility in food industries and confectioneries. The derived linear regression equation holds promise as a predictive tool for determining amylose content’s influence on functional parameters in FARO rice samples.