Effect of rice variety and milling fraction on the starch gelatinization and rheological properties of rice milk

This study aimed to investigate the rheological properties of rice milk produced from raw rice including rice varieties and milling fractions. Rice milk was prepared from two rice varieties, which were Arhent (long grain) and Bengal (medium grain) using brown, head and broken fractions of the two cultivars used. Gelatinization temperatures for each rice variety, milling fraction, and rheological behaviors of rice milk were examined. Flow behaviors of rice milk were significantly affected by the variety and milling fractions of raw rice. The different amylose to amylopectin ratios of the two varieties, the compositional differences and the subsequent impact on the gelatinization temperature of raw rice used in rice milk were the primary reasons for these differences. Rice milk prepared from Bengal showed greater consistency coefficients, showing a Newtonian flow behavior compared to the rice milk made from Arhent variety. Broken rice showed a potential to be as a raw material in the rice milk industry since it showed similar flow properties compared to the head rice (i.e. within the same variety).