小刀蛏软体部营养成分分析及评价

Analysis of Nutritional Composition of Edible Parts of Cultellus attenuatus Dunker

测定小刀蛏软体部营养成分,并与部分经济蛏类进行比较。结果表明:小刀蛏含肉率为57.58%,软体部(鲜质)中水分、粗蛋白、粗脂肪和粗灰分的含量分别为83.01%、10.83%、1.17%和2.03%。软体部(干质)中检测出17种氨基酸,总量为54.10%,其中必需氨基酸总量为19.46%,占氨基酸总量的35.97%,必需氨基酸与非必需氨基酸比值为71.99%,构成比例符合FAO/WHO规定的优质蛋白质标准。6种鲜味氨基酸(FAA)总量为24.97%,占氨基酸总量的46.15%。根据氨基酸评分和化学评分计算结果,小刀蛏软体部的第一限制性氨基酸为蛋氨酸+胱氨酸(Met+Cys),第二限制性氨基酸为缬氨酸(Val),必需氨基酸指数为66.83,支链氨基酸和芳香族氨基酸含量的比值为1.88。小刀蛏软体部不饱和脂肪酸含量占脂肪酸总量的67.28%;多不饱和脂肪酸(PUFA)占脂肪酸总量的36.48%,其中二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)共占PUFA的71.22%,ω-3 PUFA含量明显高于ω-6PUFA含量;多不饱和脂肪酸和EPA、DHA含量与其他蛏类相近。营养品质评价结果表明:小刀蛏软体部具有较高的食用价值与保健作用。

The nutritional composition of edible parts of Cultellus attenuatus Dunker grown in Haizhou bay was investigated and compared with other razor clams. The results showed that the yield of edible parts of Cultellus attenuatus Dunker was 57.58 %, and the contents of moisture, crude protein, crude fat and crude ash in fresh edible parts of C. attenuatus were 83.01%, 10.83%, 1.17% and 2.03%, respectively. A total of 17 types of amino acids were detected in the edible parts of C. attenuatus. In dry samples, the total content of amino acids was 54.10%. Among them, the contents of essential amino acids, half-essential amino acids, nonessential amino acids and delicious amino acids were 19.46%, 7.61%, 27.03% and 24.97%, respectively. The ratio of total essential amino acids to total amino acids was 35.97%, and the ratio of total essential amino acids to total nonessential amino acids was 71.99%. This amino acid composition met the FAO/WHO standards for high quality protein. According to nutritional evaluation based on amino acid score and chemical score, the first limiting amino acid was Met ＋ Cys and the second limiting amino acid was Val. The essential amino acid index was 66.83, which was much higher than that reported for Novaculina Chinensis （36.87）. The ratio of branch-chain amino acids to aromatic amino acids was 1.88, which was lower than that of other razor clams. A toal of 27 types of common fatty acids were found in the edible parts of C. attenuatus, including 8 saturated fatty acids （SFAs）, 9 mono-unsaturated fatty acids （MUFAs） and 10 polyunsaturated fatty acids （PUFAs）. The contents of SFAs, MUFAs and PUFAs were 32.72%, 30.80% and 36.48%, respectively. In the PUFAs, the content of ω-3PUFAs was much higher than that of ω-6PUFA, and the content of EPA and DHA was 71.22%. In conclusion, this investigation indicates that C. attenuatus has high nutritional value and health benefits.