南极磷虾粉作为鲽形目鱼饲料蛋白源的营养价值评价

Evaluation of Nutrition of Antarctic Krill Meal as Dietary Protein Source for Flatfishes

中文关键词: 南极磷虾粉  鲽形目鱼  肌肉  氨基酸  脂肪酸

英文关键词: Antarctic krill meal  Flatfish  Muscle  Amino acid  Fatty acid

中文摘要:

      分析商品南极磷虾粉、自制酶解磷虾粉的主要营养成分(氨基酸和脂肪酸)组成，同时采用生化方法比较了5种鲽形目鱼肉蛋白的氨基酸组成。以5种鲽形目鱼肉蛋白为参比蛋白，利用必需氨基酸指数、氨基酸比值系数分和关联度分析法评价南极磷虾粉作为鲽形目鱼饲料蛋白源的营养价值，同时对2种磷虾粉的氟含量进行了分析。结果显示，鲽形目鱼肉(干样)中含有16种常见氨基酸，其中，7种为人体必需氨基酸，4种为呈味氨基酸(总量分别为28.52%–38.03%、25.26%–33.56%)；5种鲽形目鱼氨基酸组成均符合FAO/WHO的理想模式。南极磷虾粉和酶解磷虾粉的粗蛋白分别为60.84%和68.60%，粗脂肪分别为12.08%和10.79%，达到了规定鱼粉的一级品甚至特级品的指标。酶解处理后蛋白含量显著升高(P<0.05)，脂肪含量显著下降(P<0.05)，灰分含量无差异(P>0.05)。从必需氨基酸指数(EAAI)来看，EAAI均大于0.95，磷虾粉的必需氨基酸与鲽形目鱼的必需氨基酸拟合度较高。从氨基酸比值系数分(SRC)和关联度分析法来看，2种磷虾粉对于鲽形目鱼的必需氨基酸平衡性较好，相关系数与鱼粉相差不大。氟含量方面，酶解后磷虾粉的氟含量[(331.21±6.70) mg/kg]显著降低(P<0.05)，低于欧盟标准(350 mg/kg)。综合来看，2种磷虾粉氨基酸平衡性较好、营养价值较高，是优质蛋白源。

英文摘要:

      In this study we evaluated the contents of major nutrients including amino acids and fatty acids of two krill meals, Antarctic krill meal and hydrolyzed krill meal, and analyzed the muscle samples of five species of flatfishes, Verasper Variegates, Platichthys stellatus, Platichthys biocoloratus, Verasper moseri, and Scophthalmus maximus. The nutritional values of the two krill meals were tested with the essential amino acid index, score of ratio coefficient of amino acid, and relativity of essential amino acids, and the levels of fluorine in the two krill meals were also measured. Sixteen kinds of amino acids were found in muscles of five flatfishes, including seven essential amino acids and four flavor amino acids. The amino acid composition of muscles of the five flatfishes complied the standards of Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO). The contents of crude proteins in Antarctic krill meal and hydrolyzed krill meal were 60.84% and 68.60% respectively, which satisfied the standards of the first class products index and the superfine products index. After hydrolysis, the content of crude proteins was significantly increased (P<0.05), whereas the content of crude lipids dropped (P<0.05). The content of ash was unaltered (P>0.05). These results suggested that there was a good balance in the amino acid composition of the two krill meals, and that the relativity of essential amino acids was similar to the fish meal. In addition, the content of fluorine in the hydrolyzed krill meal was significantly lower than that in the Antarctic krill meal (P<0.05). In conclusion, Antarctic krill meal and hydrolyzed krill meal had high nutritional values and potentially could be largely employed in aquaculture feeds.