水库网箱和池塘养殖斑点叉尾（鱼回）肌肉营养成分和品质的比较分析

为了了解池塘和水库网箱两种养殖模式下斑点叉尾鮰（Ictalurus punctatus）肌肉营养成分和品质特性，利用生化分析、物性分析方法和电感耦合等离子体原子发射光谱法分别对斑点叉尾鮰肌肉的常规营养成分、系水力、质构特性及肌肉矿物元素含量进行了测定。结果显示，池塘和水库网箱养殖的斑点叉尾鮰含肉率都在65%以上；池塘组的贮存损失和失水率显著低于水库网箱养殖组，而冷冻渗出率显著高于水库网箱养殖组；水库网箱养殖组的粗蛋白、粗灰分含量均显著高于池塘组，而粗脂肪含量显著低于池塘组；两组中矿物元素含量都比较丰富，水库网箱养殖组肌肉中钾、磷、钙、镁、锌、铁六种元素的含量均显著高于池塘组；池塘组肌肉的凝聚性和回复性显著高于水库网箱养殖组，而肌肉硬度、胶黏性和咀嚼性显著低于水库网箱养殖组。研究表明，池塘养殖的斑点叉尾鮰肌肉具有较好的系水力，而水库网箱养殖的斑点叉尾鮰肌肉具有高蛋白低脂肪、矿物元素更丰富、肉质硬度大的特点。

Comparative study on muscle texture profile and nutritional value of channel catfish(Ictalurus punctatus)reared in ponds and reservoir cages

In order to understand the muscle nutritional value and texture profile of channel catfish Ictalurus punctatus reared in ponds and reservoir cages, the nutritional composition, the water holding capacity and texture profile of muscle in channel catfish Ictalurus punctatus were investigated. The crude protein, crude fat, crude ash, and moisture of muscle in channel catfish were assayed by biochemical analysis methods. The muscular contents of mineral elements were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The parameters of muscular texture profile, including hardness, springiness, cohesiveness, gumminess, chewiness, and resilience, were analyzed using a texture analyzer. Double compression was applied to construct the texture profile analyses (TPA) on raw fillets. The results showed that the rate of flesh content in catfish reared in either pond or cage group was more than 65%. Flesh leaching loss increased significantly in the pond group than those in the reservoir group. Compared to the catfish in the pond group, a significantly lower value in either drip loss or liquid loss was observed in the catfish in the reservoir group. The catfish exhibited higher contents of crude protein and crude ash in the reservoir group than the pond group. A significantly higher crude fat was found in the catfish in the pond group. The catfish reared either in pond or in reservoir had rich mineral elements content in muscle. Compared to the pond group, a significantly higher content of potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), zinc (Zn), and iron (Fe) was observed in the reservoir group. However, there were no significant differences in sodium (Na), copper (Cu), manganese (Mn), and chromium (Cr) between the pond group and the reservoir group. No selenium (Se) was detected in fish muscle of both groups. The calcium-phosphorus ratios of muscle in the pond group and the reservoir group were 1:22.6 and 1:21.1, respectively. The hardness, gumminess, and chewiness of muscle enhanced significantly in the catfish in the reservoir group than those in the pond group. The pond group had significant higher resilience and cohesiveness than the cage group. Given the results, the muscle of catfish showed higher water holding capacity in the pond group, whereas the catfish muscle in the reservoir group contained higher protein, lower fat, richer mineral elements content, and higher hardness.