Using Xinzheng jujubes as experimental material, the effects of different relative humidity (continuous dehumidification, 40%, 50%, 60%) on internal temperature rise, drying time, energy consumption, and sensory quality of jujubes were studied. The jujubes were dried at 35-65 ℃ with constant wind speed (1 m/s) and humidity. The internal temperature of jujube was measured by T-type thermocouple and data acquisition instrument, and the energy consumption during drying was recorded by electric energy meter. The results showed that increasing relative humidity of hot air could increase the internal heating rate of red jujubes and avoid skins hardening. Moreover, the internal moisture migration rate of red jujubes increased, which improved overall drying rate, shortened the drying time and reduced energy consumption during drying. When the relative humidity was 60%, the drying time and energy consumption during the whole stage reduced by 15.38% and 34.78%, respectively, compared against that of continuous dehumidification, and the dried jujube products shrank evenly with bright color. Overall, current research provides a theoretical basis for improving the drying rate and drying quality, as well as for reducing energy consumption when drying jujubes.
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