An Application of Image Analysis to Model Changes in Millet Kernel Water Absorption and Dimensions During Hydration at Different Temperatures

Abstract

In the present study, image analysis was introduced to study the water absorbing expansion and water absorption kinetics of two minor millets (Barnyard and Foxtail millet) at temperatures of 30-75°C. The water absorption and water absorbing expansion kinetics of millets during hydration were studied using six and four model equations respectively. The findings proved in the water absorption behavior of millet kernels when the hydration temperature increased from 30 to 75 °C and the hydration time decreased with an increase in hydration temperature. It was evaluated that the six model equations can accurately describe the changes in water absorption behavior in Barnyard and Foxtail millet after hydrating at 30, 45, 60, and 75 °C. Millet water absorption was best determined using the Page and two-term model. In addition, millet kernels' dimensional features grew from 30 to 60 °C, but declined beyond 60 °C. Weibull, Kaptso, Peleg, and Fick's models accurately described hydrated millet kernel dimensional changes at different temperatures and times. The best fit was the Weibull model. Barnyard and foxtail millet water absorption expansion was predicted by changing model coefficients in linear and polynomial equations.