[目的]为提高杏子干燥品质及市场竞争力,[方法]本文将热风技术应用于杏子的干燥,研究不同干燥温度和风速对杏子干燥收缩特性及色泽的影响.[结果]在热风干燥过程中,杏子干燥收缩率随干燥温度或风速的增加均呈现先增加后减小的趋势;在干燥温度为50℃,风速为6 m/s时,杏子的干燥收缩率达到最大值45.25％;考虑收缩计算的杏子水分有效扩散系数随干基含水率的减少呈先增加后减小的变化趋势,与不考虑收缩相比其值小一个数量级;杏子收缩活化能为20.67 kJ/mol;温度对干燥后杏子的色泽变化有重要影响,随着干燥温度的增加,a*值和b*值逐渐增加,而L*值逐渐减小,但风速对L*、a+和b+值的影响不大.[结论]该研究对杏子干燥后体积的留存及色泽变化的规律性提供了理论参考.%[Objective] The present study was conducted to improve the apricot drying quality and market competitiveness.[Method] Hot-air was applied to drying apricot,and the effects of different drying temperatures and air velocities on the shrinkage characteristics and color change of drying apricot were investigated.[Result] The shrinkage rate of apricot appeared to increase and then decrease with the increase of air temperature or air velocity;Its shrinkage rate reached the maximum of 45.25 ％ when the drying temperature was 50 ℃,and air velocities was 6 m/s;Considering its shrinkage characteristics,the moisture effective diffusivity coefficient of apricot appeared to increase and then decrease with the decrease of moisture content in dry basis,and the value of moisture effective diffusivity coefficient was smaller of a magnitude than that without considering shrinkage;The shrinkage activation energy of apricot was 20.67 kJ/mol;The drying temperature had a significant effect on the drying processing,a * and b * values appeared to increase with the increase of drying temperature,but L * values decrease;The air velocities had a little effect on L *,a * and b * values.[Conclusion] This research provided a theoretical reference for shrinkage characteristics and color change of apricot using hot-air drying technology.
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