Effects of hot air drying on the kinetics and characteristics of pregelatinized corn grits

The sun drying of partially gelatinized corn grits can take 1-3 days and result in an unfavorable odor and inconsistent quality of the final products. This research aimed to investigate the effect of hot-air drying (HAD) temperature on the drying kinetics and characteristics of pregelatinized corn grits. The effect of various HAD temperatures (50- 70°C) on the characteristics of pregelatinized corn grits, such as microstructure, water absorption index (WAI), water solubility index (WSI), and yellowness index (YI), as well as the textural properties of rehydrated pregelatinized corn grits, was analyzed. Results showed that temperature was a significant factor (p<0.05) affecting the drying kinetics of pregelatinized corn grits. A high drying temperature increased the drying rate, homogeneity of surface pores, and WAI of dried pregelatinized corn grits, as well as reduced the hardness and increased the adhesiveness of rehydrated pregelatinized corn grits.