大西洋鲑和虹鳟不同部位中虾青素和脂肪酸的比较分析

Comparison of astaxanthin and fatty acid in different parts of farmed Salmo salar and Oncorhynchus mykiss

对养殖大西洋鲑(Salmo salar)和虹鳟(Oncorhynchus mykiss)不同部位(鱼皮、背肌、腹肌和尾肌)中虾青素和脂肪酸的组成和含量进行比较分析。结果表明,大多数大西洋鲑和虹鳟肌肉样品中虾青素的立体异构体组成(3S,3′S∶3R,3′S∶3R,3′R≈1∶2∶1)与化学合成虾青素相当。大西洋鲑和虹鳟肌肉中的虾青素均以游离态全反式结构存在,而鱼皮中为游离态和酯态;虹鳟肌肉中虾青素含量[(8.31±0.98)~(11.23±1.98)mg/kg]高于大西洋鲑[(7.12±1.32)~(9.17±2.04)mg/kg],但无显著差异(P>0.05),而鱼皮中虾青素含量显著高于大西洋鲑(P<0.05);2种鱼尾肌中虾青素含量最高,背肌和腹肌次之,鱼皮中最低。大西洋鲑和虹鳟中脂肪酸组成丰富,但不同部位间存在差异,背肌和腹肌中脂肪酸种类较多,含有16~18种脂肪酸;此外,2种鱼的脂肪酸含量差异较大,虹鳟腹肌和背肌中总饱和脂肪酸、总单不饱和脂肪酸和总多不饱和脂肪酸含量均显著高于大西洋鲑(P<0.05),特别是C18∶3 n-3(α-亚麻酸)和C22∶6 n-3(二十二碳六烯酸)含量显著高于大西洋鲑(P<0.05);2种鱼多烯指数、动脉粥样硬化指数和血栓形成指数值无显著差异,且不同部位间也无显著差异。综上,养殖大西洋鲑和虹鳟体内的虾青素主要来源于化学合成虾青素,虹鳟中虾青素、α-亚麻酸和二十二碳六烯酸含量较高于大西洋鲑,不同部位间存在差异,但它们均为优质的养殖鱼类,具有较高的食用价值。

The composition and content of astaxanthin and fatty acids in different parts(fish skin,dorsal muscles,ventral muscles and tail muscles)of farmed Oncorhynchus mykiss and Salmo salar were compared and analyzed.The results showed that the stereoisomer composition of astaxanthin in most Salmo salar and Oncorhynchus mykiss were mostly 3S,3′S∶3R,3′S∶3R,3′R≈1∶2∶1,which was equivalent to chemically synthesized astaxanthin.The astaxanthin existed in free form in their muscles,while the fish skin contained free astaxanthin and esterified astaxanthin.The content of astaxanthin in Oncorhynchus mykiss muscles[(8.31±0.98)-(11.23±1.98)mg/kg]was higher than Salmo salar[(7.12±1.32)-(9.17±2.04)mg/kg],but there were no significant difference(P>0.05).While in fish skin,the content of astaxanthin in Oncorhynchus mykiss was significantly higher than Atlantic salmon(P<0.05).The two species of fish had the highest astaxanthin content in tail muscles,followed by ventral,dorsal muscles and fish skin.Both types of fish were rich in fatty acid compositions,but there were differences between different parts.Moreover,many types of fatty acids in the ventral and dorsal muscles which containing 16-18 kinds of fatty acids.In addition,the fatty acid content of the two fishs was quite different.And the contents of total saturated fatty acids,total monounsaturated fatty acids and total n-3 polyunsaturated fatty acids in the dorsal and ventral muscle of Oncorhynchus mykiss were significantly higher than those of Salmo salar(P<0.05),especially C18∶3 n-3(ALA)and C22∶6 n-3(DHA).However,there were no significant differences in PI,IA and IT values between the two species.And no significant difference between different parts.In conclusion,the astaxanthin in farmed Oncorhynchus mykiss and Salmo salar is mainly derived from chemically synthesized astaxanthin.The content of astaxanthin,ALA and DHA in rainbow trout are higher than that of Atlantic salmon,and there are differences between different parts.But they are all high-quality farmed fish and have high food values.