澳洲龙纹斑肌肉氨基酸的分析研究

Amino Acids in Muscles of Maccullochella peelii

为研究不同生长阶段的澳洲龙纹斑肌肉氨基酸组成的动态变化,同时探讨并比较处于商品鱼阶段的澳洲龙纹斑、石斑鱼、鲟鱼肌肉氨基酸的组成与含量变化,以期推广澳洲龙纹斑的养殖技术与引导消费,本研究通过氨基酸自动分析仪检测澳洲龙纹斑亲鱼、商品鱼、幼鱼以及石斑鱼商品鱼、鲟鱼商品鱼中肌肉氨基酸含量,系统分析了澳洲龙纹斑不同生长阶段氨基酸组成的变化规律,同时比较了不同种类商品鱼氨基酸组成的含量。结果表明:3种不同生长阶段的澳洲龙纹斑氨基酸总含量最高为商品鱼70.96%、其次为幼鱼69.24%、亲鱼最低为65.36%(以干基计算),在氨基酸组成中亲鱼和商品鱼的比例较为接近,而幼鱼的氨基酸组成比例则有所变化,在必需氨基酸中,其EAA/TAA值则比亲鱼以及商品鱼低2%左右,而在非必需氨基酸中,EAA/NEAA比值又高于亲鱼与商品鱼2%左右;澳洲龙纹斑、石斑鱼、鲟鱼3种商品鱼肌肉中甜味氨基酸和鲜味氨基酸的含量之和均超过50%(澳洲龙纹斑57.17%,石斑鱼57.68%,鲟鱼57.85%),其反映了3种商品鱼肉质味道鲜美度是处在同一等级上;同时,澳洲龙纹斑商品鱼(E/T比值为40.34、E/NT比值为67.62)符合WHO/FAO提出的E/T应为40%左右和E/NT应为60%以上的参考蛋白质模式标准。

To provide information for theaquaculture and marketing purposes, the amino acid contents of Maccullochella peelii during its growth periods and at time of harvest for a comparison with groupers and sturgeonswere determined using an automatic amino acid analyzer.The results showed that the maximumtotal amino acid content of 70.96% （on dry-basis）was reached when the fish was considered marketable.They were lower for thejuveniles at 69.24% and the parent fish at 65.36%.The ratiosbetween different kinds of amino acidson the parent and marketable fish were similar,but EAA/TAA for the juveniles was approximately 2% lower,while EAA/NEAA2% higher than the others. Insofar as thepalatability as food is concerned, the meats from thethreespecies all contained more than 50% TAA （i.e,M.peeliiat 57.17%,grouper at 57.68%,and sturgeon at 57.85%）.In addition,the E/T of M.peelii was 40.34,and E/NT 67.62,which are higher than thereference standardsset for the protein by WHO/FAO （i.e.,40% for E/Tand greater than 60% for E/NT）.