微波功率对月柿果片微波间歇干燥中水分迁移及品质的影响

Effects of microwave power on moisture migration and quality of persimmon slices during microwave intermittent drying

目的:探讨微波间歇干燥对月柿果片水分动态和微观结构的影响。方法:选取不同微波功率(280,350,420,490,560 W)对月柿果片进行微波间歇干燥,对干燥过程中月柿果片的水分动态和迁移进行监测,以及对月柿果片的色泽、质构、微观结构进行测定分析。结果:新鲜月柿中的水分主要以结合水(T_(21))、不易移动水(T_(22))和自由水(T_(23))3种形式存在,分别对应3个明显的水峰。随着干燥时间的延长,不易移动水和自由水的横向弛豫时间显著降低。L^(*)、a^(*)、b^(*)值随着微波功率的增加显著减小,ΔE、硬度、弹性、咀嚼性随着微波功率的增加而增加。随着微波功率的增加,果片的组织结构收缩塌陷越明显。结论:较低的微波功率能得到品质较佳的月柿干制品。

Objective:The effects of microwave intermittent drying on water dynamics and microstructure of persimmon slices were studied.Methods:Different microwave power(280,350,420,490 and 560 W)were selected to dry the persimmon slices intermittently.The moisture dynamics and migration of persimmon slices during drying were monitored,and the color,texture and microstructure of persimmon slices were analyzed.Results:There were three obvious water peaks corresponding to bound water(T_(21)),immobilized water (T_(22))and free water(T_(23))in fresh persimmon.With the increase of drying time,the transverse relaxation time of immobilized water and free water decreased significantly.The values of L^(*),a^(*)and b^(*)decreased significantly with the increase of microwave power.TheΔE,hardness,elasticity and chewiness increased with the increase of microwave power.With the increase of microwave power,the shrinkage and collapse of persimmon slices become more and more obvious.Conclusion:Lower microwave power can get better quality dried persimmon products.