深水网箱养殖和野生大黄鱼营养及品质差异性研究

On nutrition and quality differences between wild and cultured large yellow croaker Larimichthys crocea

以野生和深水网箱分阶段养殖(D0:初始、D1:第3个月、D2:第6个月)的大黄鱼(Larimichthys crocea)为对象,对其生长、色泽、粗营养、脂肪酸和氨基酸等进行比较,探究大黄鱼养殖过程的生长和品质变化规律。结果表明,养殖鱼肥满度比野生鱼约小25%,养殖鱼分阶段体长/体高和肥满度分别呈上升和下降趋势,当养殖6个月时与野生鱼无显著差异;野生鱼脂肪含量低于养殖鱼,约占养殖鱼的70%,养殖鱼脂肪含量随着养殖时间的增加而呈下降趋势,养殖鱼粗蛋白仅占野生鱼的80%左右。养殖鱼与野生鱼亮度差异不大,颜色偏红,第3和第6个月时,体色变黄;饱和脂肪酸(ΣSFA)和单不饱和脂肪酸(ΣMUFA)野生鱼>养殖鱼,多不饱和脂肪酸(ΣPUFA)和Σ(C20:5(EPA)+C22:6(DHA))野生鱼<养殖鱼,动脉粥样硬化指数(IA)和血栓形成指数(IT)野生鱼>养殖鱼,多烯指数(PI)野生鱼<养殖鱼;野生鱼和养殖鱼的非必需氨基酸(NEAA)>必需氨基酸(EAA)>半必需氨基酸(SEAA),总氨基酸(TAA)、NEAA、EAA和SEAA野生鱼>养殖鱼,支链氨基酸与芳香族氨基酸比(F)野生鱼<养殖鱼,养殖过程TAA、NEAA、EAA和SEAA均呈先升后降变化趋势,EAA/TAA、EAA/NEAA和F值呈下降趋势,而NEAA/TAA呈上升趋势。研究表明仿生态分阶段深水网箱养殖模式可有效降低大黄鱼肥满度和脂肪含量,提升鱼体色泽和营养品质,为优化大黄鱼品质和养殖技术等提供支撑。

The wild and simulated ecological staged deep-water cages cultured(D0:initial,D1:3rd month,D2:6th month)large yellow croaker were compared in body characteristics,skin color,proximate composition,fatty acids and amino acids,to explore the differences between wild and cultured large yellow croaker in nutrition,quality differences in different farmed stages.The results showed that the condition factor of deep-water cages cultured large yellow croaker was less than 25%compared to wild fish.The body length-height ratio and the condition factor of cultured fish expressed the ascending and descending trend during culture process respectively,the differences between the wild and 6th month cultured large yellow croaker were not significant.The lipid content of wild fish was lower than that of farmed fish,and had a declining trend during the farmed stages.The crude fat content of wild fish was only about 70%of that of cultured fish.The crude protein of cultured fish only reached about 80%of that of wild fish.There was no significant difference of L*between the wild and cultured fish,the cultured fish expressed red color in the initial stage,and the b*was higher in the 3rd month and 6th month.ΣSFA andΣMUFA of wild fish was significantly higher than that of cultured fish;ΣPUFA andΣ(EPA+DHA)of wild fish were lower than that of cultured fish,IA and IT value of wild fish was larger than that of cultured fish,but PI value was smaller than that of cultured fish.The wild fish and cultured fish both expressed the rule NEAA>EAA>SEAA,the TAA,NEAA,EAA and SEAA of wild fish were higher than that of cultured fish,F value of wild fish was smaller than that of cultured fish.In the culturing process,the TAA,NEAA,EAA and SEAA all expressed the ascending and descending trend,EAA/TAA,EAA/NEAA ratio and F values showed a downward trend,while the NEAA/TAA was ascending.The results showed that the simulated ecological staged deep-water cages could effectively reduce the condition factor and fat content of fish;the color and the quality of fish could be improved,the study provides support for optimizing the culture process and aquaculture techniques.