Radio frequency heating of green peas ( <i>Pisum sativum</i> L.): The improvement of heating uniformity and its dry blanching effect
Caiyue Zhang, Yuehan Dong, Yanan Sun, Yang Liu, Yequn Wang, Hongfei Fu, Xiangwei Chen, Yunyang Wang, Yunyang Wang, Yunyang Wang
Abstract
A radio frequency (RF) heating system was used to process green peas and a rotating system was introduced to improve heating rate and heating uniformity. Results revealed that rotation treatment accelerated heating rate effectively and improved heating uniformity index significantly (p < 0.05) from 0.175 (0 rpm, 55°C) to 0.029 (60 rpm, 55°C). After being treated with RF and traditional hot water blanching at 85°C, the residual lipoxygenase activities of green peas were 1.90 ± 0.71% and 35.51 ± 5.25%, respectively, confirming RF possessed better blanching efficiency. Meanwhile, weight loss, electrolyte leakage rate, color, and texture of green peas all had significant changes (p < 0.05) through RF heating. PRACTICAL APPLICATION: A rotation device can effectively improve heating uniformity of RF electromagnetic heating. The rotation device could be expanded or further developed into continuous feeding conveying device for industrial production.