The optimum conditions of process of quick-cooking brown rice using response Surface methodology

Abstract

This research aimed to study the effect of moisture content, pressure and drying temperature on texture properties of quick cooking brown rice of 2 varieties: Red Hom Mali Brown and Rice Hom Mali Brown Rice using response surface methodology (RSM) and experimental design is Central Composite Design (CCD). Hardness and chewiness were used as responses because of high R² and there is rice cooked from a microwave cooker as a reference value. The optimum conditions were overloid area of responses that have hardness and chewiness similar cooked rice. The observed value from 3 conditions and predicted values were not different at 95% level confidence. The Verification from optimum process, response value for quick cooking brown rice process with suitable condition as follows: Red Hom Mali Brown Rice was using production conditions at Initial humidity 55%, pressure 10 lb / in², and drying temperature 160°C. Hom Mali Brown Rice Brown using production conditions at Initial humidity 70%, pressure 5 lb / in² and drying temperature 200°C. The best conditions and predicted values were not different at 95% level confidence. Hardness and chewiness of rice were decreased, when increase moisture content and pressure. While higher drying temperature cause increasing in hardness and chewiness. Quick cooking rice was lower density than raw rice because expanded and porosity in kernels.