无籽刺梨与刺梨果实中氨基酸分析

Analysis of Amino Acids in Rosa sterilis and Rosa roxburghii Fruits

通过测定无籽刺梨与刺梨果实中水解氨基酸与游离氨基酸的组成和含量,探讨氨基酸组分对2种新兴水果营养与风味的影响。水解氨基酸的测试分析表明,2种成熟果实均含有全部18种氨基酸,但刺梨果实中人体所必需的8种氨基酸占总氨基酸比例为39.54%,比值系数分为66.70,高于无籽刺梨(比值系数分为59.22),表明刺梨具有更高的营养价值;相对而言,刺梨果实中蛋氨酸和半胱氨酸含量较低,而无籽刺梨果实中赖氨酸为第一限制氨基酸。对影响感官的游离氨基酸测试结果表明,精氨酸、谷氨酸、天冬氨酸与鸟氨酸(含量阈值比大于1)对刺梨果实独特风味的形成有较高贡献,而无籽刺梨果实中仅天冬氨酸的含量阈值比超过1,形成其鲜味。

In order to reveal the effects of amino acid composition on the nutritional value and flavor of Rosa sterilisi and Rosa roxburghii fruits, the contents of hydrolytic amino acids and free amino acids in the two types of fruits were determined. A total of 18 kinds of amino acids were identified. Total content of human essential amino acids（EAAs） in Rosa roxburghii fruits was 39.54% and the SRC was 66.70, which was better than that（59.22） of Rosa sterilisi fruits. These results showed that Rosa roxburghii fruits were richer in nutrients. But the content of Met ＋ Cys was insufficient as EAAs and the first limiting amino acids in Rosa roxburghii fruits, and in Rosa sterilisi fruits, the limiting AA was Lys. The flavor amino acids were also investigated. It was found that Arg, Glu, Asp and Orn contributed substantially to the unique flavor of Rosa roxburghii, and in Rosa sterilisi fruits, Asp was the only flavor amino acid.