ABSTRACT
This chapter presents the basic principles of parboiling of rice, and soaking—kinetics of soaking, half response time, finite element modeling of soaking of water by paddy, kinetics of water diffusion and starch gelatinization, steaming, drying, and effects of parboiling on milling, nutritional, and cooking qualities of rice. The chapter discusses parboiling methods such as traditional methods of parboiling and modern parboiling. It also introduces estimation of heat required for parboiling and design of parboiling tanks. Parboiling essentially consists of three main operations—namely, soaking, steaming, and drying. For parboiling, paddy soaking can be done at or below its gelatinization temperature. The lower the temperature, the slower is the process of soaking. The soaking temperature should not be more than 75°C; otherwise, the paddy will be cooked. Soaking is the most important step of the parboiling process since it provides paddy with moisture necessary for gelatinization of starch.
