不同干燥方式对菠萝品质和挥发性风味的影响

Effects of different drying methods on quality and volatile flavor of pineapple

为研究不同干燥方式对菠萝品质和挥发性风味的影响,以新鲜菠萝为原料,采用微波干燥、热风干燥和真空冷冻3种方式,分析干燥后菠萝片的感官评分、色泽、质构、营养品质,以及香气成分的变化。结果表明,热风干燥制备的菠萝片,感官评分最高,达到86分,弹性、回复性较强。真空冷冻干燥后的菠萝片维持了较好的色泽,其维生素C(V C)(837.2 mg·kg^(-1))、总糖(133.98 mg·g^(-1))、总酚(0.28 mg·g^(-1))和可溶性蛋白(0.57 mg·g^(-1))含量均高于其他处理。微波干燥后的菠萝片V C、可溶性蛋白含量最低,热风干燥后的菠萝片总糖含量最低。真空冷冻干燥与热风干燥后的菠萝片中检测到的挥发性风味成分相似,但其含量相对较高;而微波干燥后的菠萝片中检测到的挥发性风味化合物种类最少,且因局部受热不均,产生了特有的带有焦糖香的5-甲基呋喃醛、2-乙酰基呋喃等风味物质。综合营养品质与挥发性风味考虑,真空冷冻干燥制备的菠萝片品质最佳,热风干燥的次之,微波干燥处理的营养和风味损失最严重。

In order to study the effects of three common drying methods on the quality and volatile flavor of pineapple,fresh pineapple was used as raw material.Three drying methods of microwave,hot air and vacuum freeze were used to analyze the changes of sensory score,color,texture,nutritional quality and aroma components of dried pineapple slices.The results showed that the pineapple slices prepared by hot air drying had high sensory score of 86,and strong springiness and reslience.After vacuum freeze drying,pineapple slices maintained good color,and the contents of vitamin C(V C)(837.2 mg·kg^(-1)),total sugar(133.98 mg·g^(-1)),total phenol(0.28 mg·g^(-1))and soluble protein(0.57 mg·g^(-1))were higher than the other treatments.The contents of V C and soluble protein in pineapple slices dried by microwave were the lowest,while the total sugar content of pineapple slices dried by hot air was the lowest.The volatile flavor components detected in the pineapple slices dried by vacuum freeze and hot air were similar,but the contents were relatively higher by vacuum freeze drying,which could maintain the good flavor of pineapple.Yet,the least kinds of volatile flavor compounds were detected in the pineapple slices prepared by microwave drying,and unique flavor substances such as 5-methylfurfural and 2-acetylfuran with caramel flavor were produced due to the uneven local heating during drying.Given the nutritional quality and volatile flavor,the quality of pineapple slices prepared by vacuum freeze drying was the best,which was followed by hot air drying.The loss of nutrition and flavor by microwave drying was the most serious.