鱼粉中酸碱性氨基酸及呈味氨基酸含量特点研究

Study on the contents of acidic and basic amino acids and flavor amino acids in fish meal

鱼粉是养殖业最优质的动物源蛋白质饲料,但其价格昂贵,鱼粉替代研究成为饲料研究关注的热点,而饲料适口性问题是其中的难点。氨基酸作为构成蛋白质的基本物质,兼具呈味功能,并能作为重要的诱食剂。为找出鱼粉良好的适口性与氨基酸含量间的相关性,本研究通过对大量鱼粉、豆粕、鸡肉粉和DDGS中氨基酸含量的测试,比较分析其中16种氨基酸含量、酸碱氨基酸含量以及酸、甜、苦、鲜四种呈味氨基酸含量的特点,结果发现鱼粉中氨基酸总量越高,Met、Lys、Thr、His、Leu、Ile及Tyr含量的占比越高,Glu、Gly、Pro和Phe含量占比越低,Ser、Ala、His、Arg和Phe含量占比则没有显著差异(P≥0.05);鱼粉中酸、碱氨基酸含量比值以及酸、甜、苦、鲜四种呈味氨基酸的比值分别稳定在25.18和37.25.20.18。

Fish meal is the top-quality protein feed for animal husbandry, but due to its expensive price, the studies on exploring alternatives for fish meal have become a hot spot for feed research. With- in all the concerns, feed palatability is one of the most challenge issues to resolve. Amino acids, as basic elements assembling proteins, are taste-active compounds therefore are considered as important tastants for animals. In order to analyze the correlation between palatability and amino acid content of fish meal, comparative investigation of the composition of 16 different types of amino acids, acidic and basic amino acids as well as four taste-active amino acids imparting the taste of sour, sweet, bitter and umami were performed in fish meal, soybean meal, chicken meal, and DDGS. The results from current study presented that the proportions of Met, Lys, Thr, His, Leu, Ile, and Tyr have a positive correlation to total amount of amino acids, the proportions of Glu, Gly, Pro and Phe showed a negative correlation instead in fish meal. In the meanwhile, there is no statistical difference （P≥0.05） detected for the proportions of Ser, Ala, His, Arg and Phe in the samples we tested. The ratio of acidic to basic amino acids was stable at 25 ： 18, while the ratio of four types of flavor amino acids stays consistently at 37：25 ： 20 ：18.