冷榨脱脂核桃仁的营养和蛋白质特性分析

Analysis of Nutrition and Protein Characteristics of Cold-pressed Degreased Walnut Kernel

近年来,随着核桃产量和核桃深加工发展,核桃油成为加工热点。大量核桃粕因含有核桃内果皮而被废弃或作为饲料,造成蛋白资源浪费。试验对液压冷榨后的核桃粕基本组成、蛋白质氨基酸构成及其分子量进行研究,以期对脱脂核桃蛋白进行合理利用,使其成为人类蛋白资源。核桃粕成分分析表明,蛋白质、脂肪、水分、灰分及碳水化合物含量依次为50.20%,24.67%,7.82%,5.80%及11.51%;氨基酸分析发现,其含有16种氨基酸,包含6种人体必需氨基酸,含量最高的氨基酸是谷氨酸,为70.17 mg/g,其次是精氨酸,为62.24 mg/g,酪氨酸含量最低,为0.41 mg/g。核桃粕核桃蛋白质分子量分布研究表明,核桃蛋白质分子亚基约14条,分布范围在7.8~97.4 k Da,主要集中于23.49k Da和37.41 k Da。

With the increase of walnut yield and walnut deep processing,walnut oil had become a processing hotspot.A large amount of walnut meal was discarded or used as feed because it contains walnut endocarp,resulting in waste of protein resources.The basic composition of cold-pressed walnut meal and the amino acid composition of protein and its molecular weight were studied in order to make rational use of degreased walnut kernel and extract it as human protein resource.It was hoped that the skimmed walnut kernels could be rationally utilized and extracted as human protein resources.The components analysis of defatted walnut kernels showed that protein,fat,water,ash and carbohydrate contents were 50.20%,24.67%,7.82%,5.80%and 11.51%,respectively;Amino acid analysis showed that it contained 16 kinds of amino acids,including 6 kinds of essential amino acids for human body.The highest content of amino acids was glutamic acid 70.17 mg/g,followed by arginine 62.24 mg/g,and the lowest content of tyrosine was 0.41 mg/g.The molecular weight distribution of walnut protein in degrease walnut kernel showed that there were about 14 walnut protein subunits,with a distribution range of 7.8-97.4 k Da,mainly concentrated in 23.49 k Da and 37.41 k Da.