鲢和罗非鱼不同精细分割部位的冷藏品质变化规律

Quality changes of fine-segmented silver carp and tilapia products during the refrigeration process

摘要:

为探究鲢（Hypophthalmichthys molitrix）和罗非鱼（Oreochromis niloticus）不同精细分割部位的冷藏品质变化规律，并筛选出易劣变部位，以鲢和罗非鱼为研究对象，将其精细分割为背脊肉、腹肋肉、腩部肉和尾部肉，在真空条件下4 ℃贮藏7 d，分析其贮藏前后的感官评价、生化指标和质构特性等指标。结果显示，贮藏7 d后，两种鱼各部位的感官评价都有不同程度的下降，且鲢腩部的气味劣变程度最大。0 d鲢背脊肉与尾部肉的挥发性气味轮廓相似，第7天两种鱼各部位间PCA分离度变大。在7 d贮藏期内，鲢不同部位的鱼肉亮度没有显著差异，只有罗非鱼背脊肉的亮度由36.29提高到42.57。鲢的汁液流失率、离心损失高于罗非鱼，且鲢的质构特性更易劣变。从新鲜度指标综合分析，鲢背脊肉、尾部肉和罗非鱼腩部肉和尾部肉的TVB-N、K值、TVC值均显著上升，且鲢腩部肉的POV从0.09 mmol/kg显著增加至0.16 mmol/kg。鲢腹肋肉、腩部肉和尾部肉总游离氨基酸显著上升（P<0.05）。总体而言，相比腹肋肉，鲢的背脊肉、腩部肉和尾部肉的感官和鲜度品质更易劣变，罗非鱼背脊肉的感官品质和质构品质劣变最快。

Abstract:

In order to investigate the deterioration of sensory quality and physicochemical indexes among different fine-segmented fish， and screen out the parts that are susceptible to deterioration， silver carp （Hypophthalmichthys molitrix） and tilapia （Oreochromis niloticus） were finely segmented into dorsal meat， abdomen meat， belly meat and tail meat. The samples were analyzed for organoleptic evaluation， biochemical indexes and textural characteristics before and after storage. The results showed that the sensory evaluation of all parts of the two fish decreased to different degrees after 7 d of storage， and the odor of the belly of silver carp was the most deteriorated. 0 d of silver carp dorsal meat and tail meat had similar volatile odors， and the separation of PCA increased on the 7th day. During the 7-day storage period， there was no significant difference in the brightness of the different parts of silver carp， and only the brightness of the dorsal meat of tilapia increased significantly from 36.29 to 42.57. The drip loss and centrifugal loss of silver carp were higher than tilapia， and the texture profile of silver carp were more likely to deteriorate. From the comprehensive analysis of freshness indexes， the contents of TVB-N， K value， and TVC value of silver carp dorsal， tail meat， tilapia belly， tail meat were significantly increased， and the POV of chub belly meat increased significantly from 0.09 mmol/kg to 0.16 mmol/kg （P<0.05）. Total free amino acids increased significantly in rib meat， belly meat and tail meat of silver carp. Overall， the sensory and freshness qualities of silver carp belly and tail meat were more susceptible to deterioration， and tilapia backbone meat deteriorated the fastest in terms of sensory quality and textural characteristics. This study provides data support for fine segmentation of freshwater fish and establishment of rapid evaluation methods.