种青养鱼模式下的草鱼肌肉营养成分和品质特性

为探究种青养鱼养殖模式对草鱼肌肉营养成分和品质特性的影响,随机选取以种青喂草为主养殖模式下养殖的草鱼(生态草鱼)和投喂人工配合饲料进行养殖的草鱼(饲料草鱼)各16尾,测定其肌肉系水力和质构特性指标,以及肌肉常规营养成分、矿物元素、氨基酸和脂肪酸含量。结果显示,生态草鱼和饲料草鱼肝体比和空壳率无显著性差异;生态草鱼肌肉系水力指标中滴水损失显著低于饲料草鱼,冷冻渗出率不显著地低于饲料草鱼,失水率不显著地高于饲料草鱼,p H值无显著性差异;肌肉的硬度、弹性、凝聚性、胶黏性和回复性均无显著性差异;生态草鱼粗脂肪含量显著低于饲料草鱼,水分、灰分、粗蛋白含量均无显著性差异;生态草鱼P和Fe含量均显著高于饲料草鱼,Mg、Mn和Cr含量均极显著高于饲料草鱼;生态草鱼和饲料草鱼肌肉氨基酸组成基本一致,均含有17种氨基酸,其中人体必需氨基酸总量分别为6.85%和6.27%。生态草鱼必需氨基酸指数(EAAI)为76.07,而饲料草鱼为77.29,饲料草鱼略高于生态草鱼。生态草鱼和饲料草鱼肌肉均含19种脂肪酸,其中棕榈酸、花生四烯酸(ARA)、亚油酸(LA)、油酸、二十二碳六烯酸(DHA)和硬脂酸含量较高,为主要脂肪酸,而花生五烯酸(EPA)+DHA含量分别为8.95%和10.70%,且差异显著。研究表明,生态草鱼和饲料草鱼在肌肉质构特性方面无显著性差异,与饲料草鱼相比,生态草鱼具有肌肉系水力强、低脂肪和矿物元素含量高的特点。

The study of muscular nutritional components and fish quality of grass carp (Ctenopharyngodon idella) in ecological model of cultivating grass carp with grass

To investigate the effects of muscular nutritional components and fish quality of grass carp (Ctenopharyngodon idella) in ecological model of cultivating grass carp with grass, the ecological grass mainly fed with grass and feed grass carp fed with artificially formulated feed, respectively 16 individuals, were randomly selected to measure some indicators. These indicators included water holding capacity and texture profiles parameters in muscle, contents of nutritional components, mineral elements, amino acids and fatty acids in muscle. The results showed no significant difference in hepatosomatic index and shell rate between ecological grass carp and feed grass carp. Compared with these feed grass carp, significantly lower value in drop loss, no significantly lower value in flesh leaching loss, no significantly higher value in liquid loss and no significant difference in pH value were observed in muscle of ecological grass carp. Hardness, springiness, cohesiveness, gumminess and resilience in muscle had no significant difference between ecological grass carp and feed grass carp. The content of crude fat in muscle of ecological grass carp was significantly lower than that of feed grass carp, while the contents of moisture, ash and crude protein in muscle had no significant difference. The contents of phosphorus (P) and iron (Fe) in muscle of ecological grass carp were significantly higher than those of feed grass carp, and the contents of magnesium (Mg), manganese (Mn) and chromium (Cr) in muscle of ecological grass carp were very significantly higher than that of feed grass carp. The compositions of amino acids of ecological grass carp and feed grass carp were basically the same, containing 17 amino acids, wherein the essential amino acids in muscle is 6.85% and 6.27%, respectively. The essential amino index (EAAI) of feed grass carp (77.29) was higher than that of ecological grass carp (76.07). The ecological grass carp and feed grass carp both contained 19 fatty acids where in the contents of palmitic acid, arachidonic acid (ARA), linoleic acid (LA), oleic acid, docosahexaenoic acid (DHA) and stearic acid were high, as the main fatty acid. The contents of eicosapentanoic (EPA) + docosahexaenoic acid (DHA) had significance difference (were 8.95% and 10.70%, respectively). These results indicated that there was no significant difference in muscular texture profiles. The ecological grass carp had characteristics of higher water-holding ability, lower content of fat and higher content of mineral elements than those in muscle of feed grass carp.