香港牡蛎挥发性成分及其加热处理变化

Analysis of Volatile Components in Hongkong Oyster Meat and Its Changes after Heating Treatment

【目的】研究香港牡蛎加热处理前后的挥发性成分变化及其变化原因。【方法】采用顶空固相微萃取与气相色谱-质谱联用技术(solid phase micro-extraction gas chromatographmass spectrometer,SPME-GC/MS)分析香港牡蛎肉挥发性风味成分,结合感觉阈值,利用相对气味活度值(relative odour active value,ROAV)确定牡蛎熟制前后的主要挥发性风味成分,描述主要挥发性风味成分的气味特征并分析其生成途径。【结果与结论】加热处理前后牡蛎的挥发性成分发生明显变化,从鲜牡蛎和熟制牡蛎中分别鉴定出101种和107种风味物质,主要物质有醛、醇、酮、酸、烃、酯、酚类等,对气味影响最大的醛类化合物由熟制前的26种增加到熟制后的30种,相对含量却由熟制前的33.25%减少到熟制后的14.65%,酸类化合物由熟制前的7种增加到熟制后的19种,相对含量却由熟制前的8.82%增加到熟制后的32.98%。熟制后酯类化合物在种类和含量上都有所增加。

【Objective】This paper studies the changes of volatile components and flavor of cooked Crassostrea hongkongensis flesh comparing with that of the fresh Crassostrea hongkongensis flesh.【Method】Using solid phase micro-extraction gas chromatographmass spectrometer technology , this paper tries to analyze the components of the fresh and cooked C. hongkongensis flesh’ volatile flavor. Then combining with sensory threshold, the critical components of fresh and cooked oyster pulping fluid relish were respectively confirmed by using relative odor active value. What characteristic the volatile flavor had and how the flavor was generated were also analyzed in this paper. 【Result and conclusion】The results show that the volatile components of oyster pulping fluid are markedly changed in the cooked oyster pulping fluid as compared to the fresh oyster pulping fluid. A total of 101 kinds of components in fresh and 107 kinds in cooked oyster pulping fluid were respectively confirmed. They were mainly aldehydes, alcohols, ketones, acids, hydrocarbons, esters, phenolics, and so on. The kind of aldehyde compound that is the most influential material to oyster pulping fluid’ odor increased from 26 in the fresh oyster to 30 in the cooked oyster, but the relative contents of aldehyde compounds decreased from 33.25% to 14.65% , which might be the reason for decreased in that the fruity flavor and green odor of cooked oyster pulping fluid were decreased and the increase in fishy odor. It was caused primarily by fat oxidation, the number of acid compound increased from 7 in the fresh oyster to 19 in the cooked oyster, but the relative contents of aldehydes decreased from 88.2% to 32.98%, which is the main reason for contribute the rancidity and pungent smell of the cooked oyster. For ester compounds, both its numbers and the contents are increased, which contribute to the increase of the meat flavor.