Drying characteristics of white radish slices under heat pump — Low-temperature regenerative wheel collaborative drying
Junhai Yan, Weinan Han, Ben Wei, Yin Liu, Long Gao, Long Wang, Song Wang, Mingru Zhu, Ziheng Huo
Abstract
To address the issues of low efficiency, high energy consumption, and poor quality associated with traditional food drying methods, this study proposes a heat pump–low-temperature regeneration wheel collaborative drying system. This system offers advantages such as a fast drying rate, high food drying quality, and low energy consumption. To further investigate its drying characteristics, drying experiments were conducted on white radish slices at temperatures of 35 °C, 40 °C, and 45 °C. The results indicate that, compared to heat pump drying, the collaborative drying mode exhibits significant advantages: drying time was greatly reduced, with a minimum reduction of 60 min at all temperatures. The maximum drying rate increased significantly, ranging from 17.04 % to 19.51 %. Energy consumption was noticeably reduced, decreasing by 7.48 %–11.68 %. Moreover, the effective moisture diffusivity improved by 7.98 %–11.49 %, product shrinkage decreased by 4.00 %–5.56 %, rehydration ratios increased by 3.25 %–8.20 %, and sensory evaluation improved by 17.29 %–38.09 %. Additionally, based on the experimental data, the Wang and Sing model was determined to be the most suitable mathematical model for describing the collaborative drying process, exhibiting a coefficient of determination (R 2 ) exceeding 0.999. This research demonstrates that the heat pump–low-temperature regeneration wheel collaborative drying system has significant potential for market application due to its high product drying quality and low energy consumption.