洞庭青鲫肌肉营养成分分析及营养价值评定

对2002年在湖南澧县澧水尾闾、洞庭湖区边缘化的封闭型湖泊——北民湖发现的洞庭青鲫(Carassius auratus var.dongtingking)(n=15)的含肉率和肌肉中的生化成分、比能值及氨基酸测定分析。结果表明,洞庭青鲫的含肉率为52.18%;其肌肉生化成分(鲜重百分比)为:水分78.14%,蛋白质18.63%,脂肪1.51%,灰分1.22%,比能值5.09kJ/g及E/P值27.32kJ/g。肌肉中含有17种氨基酸,总量为866.12mg/g(干重比);其中9种人体必需氨基酸含量占氨基酸总量的48.21%(盐酸水解法);支/芳值达2.81,接近人体正常所需;4种鲜味氨基酸占氨基酸总量的50.39%。根据氨基酸评分(AAS)和化学评分(CS)标准,洞庭青鲫的第一限制因子是甲硫氨酸和胱氨酸,其次是缬氨酸、苯丙氨酸和酪氨酸。即洞庭青鲫氨基酸含量与组成与彭泽鲫(C.a.var.pengze)、异育银鲫(C.a.var.allogynogeneticrp)、萍乡肉红鲫(C.a.var.pingxing red)相比,均存在差异。

Analysis of Nutritional Composition and Evaluation of Nutritional Quality in Muscle of Carassius auratus var.dongtingking

The present paper deals with the ratio of flesh in whole body and analysis of the nutritive composition,energy and amino acids of muscle in Carassius auratus var.dongtingking,an endemic fish living in the edge of Dongting Lake,based on 15 individuals collected from the Beiming Lake at Hunan Lixian in Mainland China in 2002.It was showed that the ratio of flesh to body was 52.18%,the ratio of gill in whole body was only 4.03%;analysis results of the nutritive composition(%,wet)were that:the moisture of muscle was 78.14%,protein 18.63%,fat 1.51%,ash 1.22%.The content of energy was 5.09 kJ/g,E/P was 27.32 kJ/g.A total of 17 common amino acids and 9 essential amino acids for human needs can be found in muscle.The total content of amino acids was 866.12 mg/g(dry);the content of essential amino acids was 48.21%;essential amino acids gram to total nitrogen gram(E/TN)was 2.81.By nutrition evaluation for the amino acids in muscle to human needs,the content of 4 kinds delicious amino acids was 50.39%;according to the amino acids score(AAS),the first limited amino acid was Met and Cys and the second limited amino acid was Val.;on the basis of chemical score(CS),the first and second limited amino acids was the same as the ASS.The results shows that the contents and composition of amino acids in muscle of C.a.var.dongtingking differ with those in three species Crucian Carp(C.a.var.pengze,C.a.var.allogynogenetic and C.a.var.pingxing red).