2016 Volume 22 Issue 2 Pages 159-172
Roasting with superheated steam as the medium are used to obtain gelatinized rice for “green” Chinese wine brewing. The microstructure, pasting properties and starch crystal of rice are determined. That can learn the change in rice during the roasting process is considered the basis to optimize the operating parameters and enlarge the fluidized bed. It is found that the whole process can be divided into two stages, i.e., heating and puffing, with their demarcation point occurs at 20 seconds to 25 seconds after the rice is heated. Heating is a key stage of the processing that is characterized by rapid heat transfer and significant changes in the molecular structure of rice. The temperature of the rice starch needs to be controlled to prevent thermal decomposition and abiotic browning at puffing stage. Through numerical simulation analysis of rice temperature changes in the roasting process, it was found that the two stage strategy is the best mode of roasting process, and standard temperature control curve was put forward as rice temperature control reference during roasting. The comparison between air and superheated steam as two different media shows that the gelatinization effect of rice is practically the same given the same fluidized state, although superheated steam exhibits a slight advantage.