Abstract: To determine the nutritional, quality and aroma differences between soft-shelled from S. paramamosain crab and hard-shelled crab at different time points during the optimal collection period, headspace solid phase micro extraction(HS-SPME), gas chromatography-mass spectrometry (GC-MS) and relative odor activity values were used to analysis the changes of water, ash, amino acids, mineral elements and fatty acids in muscles and hepatopancreas. The results showed that the two tissues had the highest water content in soft shell crabs at 0 h, and the ash content of hard shell crabs was significantly higher than that of soft shell crabs at each time point (P<0.05). The contents of amino acids in hard shell crabs of two tissues were higher than those in soft shell crabs except for cystine and alanine in the hepatopancreas, among which the contents of leucine were significantly different (P<0.05); The contents of 12 and 14 amino acids in muscle and hepatopancreas were the highest at 6 h. The contents of Ca, Mg and Fe in the two tissues of soft shell crabs were higher than those of hard shell crabs while with no significant difference. The Ca content of soft shell crabs at 0 h was significantly higher than other time points (P<0.05). Both the 24 h soft shell crab muscle and 0 h hepatopancreas ∑PUFA content were higher than other time points. Volatile substances in the two tissues were mainly alkanes, aldehydes, ketones, alcohols, aromatic hydrocarbons, esters, phenols and ether compounds. The overall relative content was different but with no significant difference. In summary, the hepatopancreas and muscles of soft shell S. paramamosain from 0 to 6 hours were more nutritious and more flavorful than other time points, which is optimal to prepare soft shell crabs.The results of this study provide some references for the production, nutrition and flavor evaluation and market value evaluation of soft shell crab.

Key words: Scylla paramamosain, soft crabs, gas chromatography-mass spectrometry, amino acids, fatty acids, flavor

摘要： 为明确在最佳收集时间段内不同时间点的软壳蟹和硬壳蟹营养与风味物质的差异,本试验采用顶空固相微萃取(SPME)、气质联用(GS-MS)方法比较了拟穴青蟹硬壳蟹与蜕壳后0~48 h软壳蟹肌肉和肝胰腺2种组织中水分、灰分、氨基酸、矿物质元素、脂肪酸及挥发性物质含量。结果表明,软壳蟹2种组织在蜕壳0 h水分含量最高,硬壳蟹灰分含量显著(P<0.05)高于各时间点软壳蟹。除肝胰腺中胱氨酸和丙氨酸外,2种组织硬壳蟹其他氨基酸含量均高于软壳蟹,其中亮氨酸含量差异显著(P<0.05);在肌肉和肝胰腺组织中,分别有12和14种氨基酸含量均在蜕壳后6 h最高。软壳蟹2种组织Ca、Mg和Fe含量高于硬壳蟹,但差异不显著;蜕壳0 h 软壳蟹肝胰腺组织中Ca含量显著高于其他时间点(P<0.05)。蜕壳后24 h软壳蟹肌肉和0 h肝胰腺组织中∑PUFA均高于其他时间点。2种组织中挥发性物质包括烷烃类、醛类、酮类、醇类、芳香烃类、酯类、酚类和醚类化合物,总体相对含量有差异,但差异不显著。综上比较,拟穴青蟹软壳蟹蜕壳后0~6 h肝胰腺和肌肉比其他时间点更具营养、风味更加,是制取软壳蟹最佳时间。本研究结果为软壳蟹生产、营养和风味评价、市场价值评估提供了一定的参考。

关键词: 拟穴青蟹, 软壳蟹, 气相色谱-质谱联用, 氨基酸, 脂肪酸, 风味