Optimization using response surface methodology of the soaking and germination time of two rice varieties (Nerica 3 and Nerica L56) grown in the locality of Dschang (West-Cameroon).

Abstract: One of the solutions to increase children's energy intake is the use of amylase-rich flours. This led us to optimize the fluidification capacity of two paddy rice varieties. For that, the Doehlert plane-type response surface methodology was used to optimize the germinating ability of paddy rice flour (varieties Nerica 3 and Nerica L56) to fluidize cassava-based gruels by using two factors: soaking and germination time. The evaluated response was the flow velocity of the gruels. The optimization result showed that, the optimal soaking time was 48 h for the variety Nerica L56 and 12 h for Nerica 3. Concerning the optimal germination time, it was 135 h for both varieties. These conditions have been found to have the best fluidifying capacities for cassava flour-based gruels. The incorporation of 3 g germinated paddy rice flour (Nerica L56 and Nerica 3) and at optimal conditions, allowed us to obtain high flow velocities of the gruels. They were 100.00 mm/30 s and 210.66 mm/30 s respectively for the varieties Nerica L56 and Nerica 3. These flow velocities were similar to the flow velocities predicted by the model for desirabilities of 0.99 and 1.00. In view of all these results, we could therefore recommend the use of these two varieties of rice produced under these conditions to improving flow velocities, dry matter concentrations and energy bulk of the gruels. © Association of Food Scientists & Technologists (India) 2021.