冻干水蜜桃挥发性风味成分的变化及迁移

Changes and migration of volatile flavor components in freeze-dried peaches

对新鲜水蜜桃进行真空冷冻干燥试验,采用顶空固相微萃取—气相色谱/质谱联用测试方法(SPME-GC/MS),对比分析了新鲜水蜜桃、冻干水蜜桃和冻干机冷阱水中主要挥发性风味组分构成及含量。结果表明,新鲜水蜜桃、冻干水蜜桃和冷阱水中分别有26,18,11种挥发性风味化合物,主要由醛、醇、酯、烃、杂环及醚等物质构成。新鲜水蜜桃中的风味物质在冻干过程中发生了变化和迁移。大部分保留在冻干水蜜桃中的挥发性风味物质为己醛、(E)-2-庚烯醛、(E)-2-辛烯醛、苯甲醛、戊醇、己醇、(E)-2-己烯-1-醇、乙酸己酯、乙酸叶醇酯、γ-己内酯;全部迁移到冷阱水中的挥发性风味物质为壬醛、二乙二醇乙醚;冻干水蜜桃中含量增加的挥发性风味物质有(E)-2-己烯醛、芳樟醇、(E)-乙酸-2-己烯-1-醇酯;经过冻干后新生成的挥发性风味物质成分为醋酸异辛酯、2,7-二甲基萘、1,6-二甲基萘、2,3-二甲基萘。

The composition and content of main volatile flavor components in fresh peach, freeze-dried peach and lyophilizer cold trap water were compared and analyzed by SPME-GC/MS. The results showed that there were 26, 18 and 11 volatile flavor components in fresh peach, freeze-dried peach and cold trap water, respectively. They mainly included aldehydes, alcohols, esters, hydrocarbons, heterocyclics and ethers. Volatile flavor components in fresh peaches changed and migrated during freeze-drying. The retained volatile flavor components in the freeze-dried peach mainly included hexanal,( E )-2-heptenal,( E )-2-octenal, benzaldehyde, pentanol, hexanol,( E )-2-hexen-1-ol, hexyl acetate, hexyl acetate, and γ-caprolactone. Furfural and diethylene glycol ether completely migrated into the cold trap water;the contents of the freeze-dried peach slices were ( E )-2-hexenal, linalool,( E )-acetic acid-2.-hexen-1-ol ester. The content of ( E )-2-hexenal, linalool,( E )-acetic acid-2-hexen-1-ol in freeze-dried peach were increased. The newly generated volatile flavor components after freeze-drying were isooctyl acetate, 2,7-dimethylnaphthalene, 1,6-dimethylnaphthalene, and 2,3-dimethylnaphthalene.