猕猴桃加热与冷冻干燥中叶绿素和醌类物质的变化

阐明猕猴桃在加热干燥和真空冷冻干燥下的褐变情况,为猕猴桃的科学加工提供依据,对干燥过程中猕猴桃的叶绿素和醌类化合物含量变化进行了研究和分析。在加热干燥条件下,猕猴桃切片厚度为5mm和6mm,在温度60～65℃干燥时的叶绿素损失量较少,醌类化合物含量较低,样品褐变程度较轻;在温度-35℃真空冷冻干燥时,5mm厚度猕猴桃切片的叶绿素损失量较少,6mm厚度猕猴桃切片的醌类化合物含量最低,褐变程度较轻;真空冷冻干燥后的样品褐变程度明显低于加热干燥,以采取5～6mm猕猴桃切片厚度,在温度-35℃下真空冷冻干燥为宜。

Change of Chlorophyll and Quinone in Kiwi-fruit through Vacuum Freeze-drying and Hot-drying

In order to illustrate the browning change in kiwi-fruit through vacuum freeze-drying and hot-drying,and yet giving some help to scientific processing to kiwi-fruit. Content change of chlorophyll and quinone in kiwi-fruit through vacuum freeze-drying and hot-drying was studied and analyzed. In hot-drying,from 60 ℃ to 65 ℃,the loss of chlorophyll was lower in 5 mm than in 6 mm slice,the content of quinine was lower too,and there was light browning change. In -35 ℃ vacuum freeze-drying,the loss of chlorophyll was lower in 5 mm slice,the content of quinine in 6 mm slice was lowest,there was lower browning change. It was obviously indicated that the browning degree by vacuum freeze-drying was lower than by hot-drying,the preferable drying condition of kiwi was vacuum freeze-drying of -35 ℃.