变功率微波真空间歇干燥扇贝柱的研究

为解决微波真空连续干燥扇贝柱中出现的由于物料内部及边缘过热而导致的感官恶化、收缩率大、复水率低等问题,进行了变功率间歇方式干燥扇贝柱的试验研究.在真空度保持90 kPa不变,微波功率密度分别为1、2、3、4 W/g,微波间歇比分别为10s-on/20s-off、20s-on/10s-off和连续工作的试验条件下,研究了微波真空干燥扇贝柱的干燥时间、收缩率、复水率、感官品质等.结果表明:变功率干燥及间歇干燥对扇贝柱干燥速度有显著影响；间歇干燥对扇贝柱的收缩率、复水率、感官品质有明显影响；与连续干燥相比,适宜微波功率下的间歇干燥可避免焦糊、结壳现象,能改善干制品品质；本试验条件下,微波功率密度为3 W/g,间歇比为10s-on/20s-off时,变功率微波真空间歇干燥可获得很好的干品品质,扇贝柱湿基含水率达到13％需时190 min,收缩率为56.07％,复水率为66.80％.

Power-adjustable microwave vacuum intermittent drying technique of scallop adductors

In order to solve the physical and sensory problems of continuous microwave vacuum drying of scallop adductors caused by the material overheating,experiments of power-adjustable intermittent microwave vacuum drying of scallop adductors were performed.Variables including the microwave power density（1,2,3,4 W/g）,intermittent ratio（10s-on/20s-off and 20s-on/10s-off） and the vacuum degree were kept at 90 kPa.The drying time,shrinkage rate,rehydration rate and sensory characteristics of intermittent drying were compared with those of continuous drying.The results showed that the intermittent drying avoided the phenomenon of charring and incrustation,improving the dried products quality.Dried scallop adductors with pretty good sensory characteristics were produced when the microwave power density was 3 W/g and intermittent ratio was 10s-on/20s-off,and the moisture（wb） of 13% was reached within 190 min with the shrinkage rate of 56.07% and rehydration rate of 66.80%.