不同干燥方法对龙眼果肉品质特性的影响

【目的】考察不同干燥方法对去壳龙眼果肉品质特性的影响，评价微波真空干燥工艺的可行性。【方法】以龙眼果肉干制品的收缩率、复水率、色泽、多糖含量、SOD活性和感官品质为评价指标，研究热风干燥、真空干燥、微波干燥、微波真空干燥和真空冷冻干燥5种干燥方法对龙眼果肉品质特性的影响。【结果】5种干燥方法所得龙眼果肉的收缩率、复水率、色泽、多糖含量和SOD活性存在差异，微波真空干燥所制龙眼果肉的色泽最佳，收缩率、复水率、多糖含量和SOD活性仅次于真空冷冻干燥，但微波真空干燥的时间短、温度低、效率高，且所制龙眼果肉结构完整，金色饱满，质地适中，具有龙眼特有的风味，综合品质最好。【结论】微波真空干燥是最适的龙眼果肉干燥方法，可应用于工业化生产。

Effect of different drying methods on the quality of longan (Dimocarpus longan Lour.) pulp

【Objective】 Different drying methods were used to dry longan pulp in order to evaluate the feasibility of microwave vacuum drying(MVD) technology.【Method】 The qualities of longan pulp dried by hot air drying(HAD),vacuum drying(VD),microwave drying(MD),MVD,and vacuum freeze drying(VFD) were investigated,and the quality parameters were compared on the basis of shrinkage ratio,rehydration ratio,color,polysaccharides content,SOD activity,and sensory quality.【Result】 Those five drying methods were found to affect each parameter differently.The color of products dried by MVD was the best than those offered by other methods.The shrinkage,rehydration ratio,polysaccharides content,and SOD activity of products dried by MVD were slightly lower than those obtained by VFD,but microwave vacuum dried products had the highest sensory quality with structural integrity and their own unique flavors,due to short dying time,lower temperatures,and high efficiency.【Conclusion】 MVD is a novel,alternative,and potential method in food drying industry.