Effect of Temperature Mode on Quality and Kinetic Characteristics of Scomberomorus niphonius of Heat Pump Drying

In order to improve the quality of Scomberomorus niphonius products, shorten the drying time and reduce energy consumption, this paper conducted an experimental study on the heat pump drying process of Scomberomorus niphonius under constant temperature and staged rising temperature. The constant temperature drying conditions were 10, 20 and 30℃, the rising temperature drying conditions were 10℃ (3 h)~20℃ (3 h)~30℃ (end), 10℃ (6 h)~20℃ (6 h)~30℃ (end), 10℃ (9 h)~20℃ (9 h)~30℃ (end), 10℃ (12 h)~20℃ (12 h)~30℃ (end).The experiment showed that under the condition of constant temperature drying, there were corresponding deficiencies in the Scomberomorus niphonius products obtained at different drying temperatures. The use of rising temperature drying method not only can significantly shorten the drying time of Scomberomorus niphonius, but also improve product quality. The obtained products had certain advantages in terms of texture, safety and color. For constant temperature drying, the effective moisture diffusivity of Scomberomorus niphonius was between 2.0429×10^-11 and 4.1947×10^-11 m²/s in the experimental temperature range, and D_eff increased with the increase of temperature. The Page model was used to describe the heat pump drying process of Scomberomorus niphonius (R²>0.998, RMSE<0.60%, χ²<0.004%). For rising temperature drying, the effective moisture diffusivity of Scomberomorus niphonius was between 4.1164×10^-11and 4.8723×10^-11 m²/s.The Two-terms model was used to describe the process of the drying process of Scomberomorus niphonius (R²>0.996, RMSE<0.81%, χ²<0.008%). The test to determine the optimum stage of rising temperature drying process conditions was 10℃ (6 h)~20℃ (6 h)~30℃ (end).