配合饲料和冰鲜鱼养殖的中华绒螯蟹囤养期间营养品质的比较

Comparison of nutritional quality of Chinese mitten crab cultured from compound feed and chilled fish during hoarding

为了解配合饲料和冰鲜鱼养殖的中华绒螯蟹(Eriocheir sinensis)囤养期间营养品质,本研究用配合饲料养殖的中华绒螯蟹和冰鲜鱼养殖的中华绒螯蟹进行为期3个月的囤养,比较可食率、常规营养物质、脂肪酸和游离氨基酸组成。结果表明:囤养期间,两种饵料中华绒螯蟹性腺指数呈上升趋势,肝胰腺指数和总可食率呈下降趋势,出肉率无显著性变化;囤养期间,两种饵料中华绒螯蟹肝胰腺水分和蛋白质含量呈上升趋势,脂肪含量呈下降趋势,性腺脂肪呈下降趋势,肌肉中营养物质无明显变化;配合饲料中华绒螯蟹可食组织(除精巢外)C18∶2n6(LA)含量显著高于冰鲜鱼中华绒螯蟹,而肝胰腺和卵巢中EPA和DHA含量显著低于冰鲜鱼中华绒螯蟹。囤养过后,配合饲料中华绒螯蟹可食组织C18∶2n6(LA)、C20∶4n6(ARA)、Σn-6PUFA含量增加且显著高于冰鲜鱼中华绒螯蟹,冰鲜鱼中华绒螯蟹可食组织EPA、DHA和Σn-3PUFA含量增加且显著高于配合饲料中华绒螯蟹;两种饵料中华绒螯蟹囤养过后肌肉当中甜味氨基酸(Gly)含量增加,而苦味氨基酸(His、Ary、Pro)含量降低,性腺当中鲜味氨基酸和甜味氨基酸含量下降。综上所述,两种饵料中华绒螯蟹囤养期间未出现明显的“掉膏”现象,但可食组织营养物质有明显的流失尤其是肝胰腺,从脂肪酸和氨基酸来看,囤养期间配合饲料中华绒螯蟹LA和ARA含量增加,冰鲜鱼河蟹EPA和DHA含量增加,整体而言囤养对中华绒螯蟹脂肪酸有一定优化作用,肌肉的甜味氨基酸含量增加,而性腺当中鲜味氨基酸和甜味氨基酸含量下降,整体品质变差。

In order to understand the nutritional quality of Chinese mitten crabs cultured with compound feed and chilled fish during hoarding,Chinese mitten crab cultured with compound feed and Chinese mitten crab cultured with fresh fish were stockpiled for three months to compare their edible rate,conventional nutrients,fatty acids and free amino acid composition.The results showed that:during the hoarding period,the gonadal index of the two bait Chinese mitten crab showed an upward trend,the hepatopancreatic index and total edible rate showed a downward trend,and there was no significant change in the meat yield;during the hoarding period,the water and protein content of liver and pancreas of the two bait Chinese mitten crab showed an upward trend,the fat content showed a downward trend,the gonadal fat showed a downward trend,and there was no obvious change in nutrients in the muscle;the content of C18∶2n6(LA)in the edible tissue(except for the fine nest)of Chinese Mitten Crab cultured with compound feed was significantly higher than that in Chinese mitten crab cultured with chilled fish,while the contents of EPA and DHA in hepatopancreas and ovaries were significantly lower than those in Chinese mitten crab cultured with chilled fish.After stockpiling,the contents of edible tissues C18∶2n6(LA),C20∶4n6(ARA)andΣn-6PUFA in Chinese mitten crab cultured with compound feed increased and were significantly higher than those in Chinese mitten crab cultured with fresh fish,and the contents of EPA,DHA andΣn-3PUFA in Chinese mitten crab cultured with fresh fish were increased and significantly higher than those in Chinese mitten crab cultured with compound feed;after hoarding the two bait Chinese mitten crab,the content of sweet amino acids(Gly)in the muscles increased,while the content of bitter amino acids(His,Ary,Pro)decreased,and the content of umami amino acids and sweet amino acids in the gonads decreased.In summary,there was no obvious“ointment”phenomenon during the hoarding of Chinese mitten crab cultured by two kinds of bait,but there was a significant loss of edible tissue nutrients,especially the liver and pancreas.From the perspective of fatty acids and amino acids,the content of LA and ARA of compound feed cultured Chinese mitten crab increased during the hoarding period,and the EPA and DHA content of chilled fish cultured Chinese mitten crab increased.On the whole,hoarding had a certain optimization effect on Chinese mitten crab fatty acids,the content of sweet amino acids in muscles increased,while the content of umami amino acids and sweet amino acids in the gonads decreased,and the overall quality deteriorated.