嫩化鲍鱼热加工风味形成规律研究

The processing of abalone with special chemical compounds and tissue structure is different from the traditional poultry and meat processing. The development of ready-to-eat abalone brings the novel challenge in flavor quality control. To resolve this problem, the aging followed cooking techniques were applied to the produce of the ready-to-eat abalone, which exhibited good quality on the tenderness and flavor. However, the formation mechanism of flavor compounds during the thermal treatment of the tenderized abalone is still not clear. Thus, the study is focused on the effect of aging on the volatile compounds in cooked abalone. In this study, the effect of aging on the flavor precursors formation is initially investigated, then the “nucleotide degradation- peptide /amino acid- unsaturated fatty acid oxidate” model reaction system is established on the basis of flavor precursors formed from the aging abalone. Subsequently, the key aroma compounds are identified by molecular sensory science and real-time flavor analysis methods. Finally, the stable carbon atom isotope labeled technique is applied to reveal the key flavor compounds formation mechanism. The study is significant on the development of abalone industry.

与传统畜禽肉制品相比，鲍鱼组织结构和营养成分特殊。为了满足现代消费者对工业化海鲜即食食品的需求而又不影响产品的最终体验，申请人所在课题组建立了一种鲍鱼嫩化熟制技术，产品具有良好的嫩度和风味品质，但嫩化改善热反应风味机制尚不明确，限制了该技术的推广。本项目拟以鲍鱼嫩化形成的前体物为基础，重新构建“核苷酸降解物-小肽/氨基酸-不饱和脂肪酸氧化产物”热反应模型体系，对嫩化鲍鱼热反应风味化合物形成机制进行研究。首先，对鲍鱼嫩化过程中化学成分及化学微环境变化规律进行研究；其次，通过分子感官组学技术和动态风味分析技术，考察嫩化鲍鱼热反应特征风味化合物的变化规律；最后，构建嫩化鲍鱼熟制模型反应体系，采用稳定同位素示踪技术以及反应中间体选择性合成技术，研究目标特征风味化合物的中间反应路径与形成机理，揭示鲍鱼嫩化与热反应风味变化的内在联系，推动鲍鱼深加工技术的发展。

本项目以鲍鱼嫩化形成的前体物为基础，通过构建模型热反应体系，对嫩化鲍鱼热反应风味化合物形成机制进行了研究。通过对嫩化鲍鱼的硬度、弹性、咀嚼度、剪切力等质构特性的对比，确定其加工工艺为80℃嫩化2h，180℃焙烤20min。对鲍鱼嫩化过程中风味前体物的研究发现，经嫩化与焙烤处理的鲍鱼样品中还原糖和二羰基化合物的含量明显增高，可溶性肌球蛋白重链和副肌球蛋白重链明显减少，而部分氨基酸含量增加，部分氨基酸含量减少，表明鲍鱼在热处理过程中不仅会发生蛋白质的降解，也会发生美拉德反应。为了进一步探究风味中间体对嫩化鲍鱼的风味影响，通过化学合成、液相色谱的分离纯化、高分辨质谱和核磁等手段的鉴定，制备出葡萄糖醛酮、3-脱氧葡萄糖醛酮等反应中间体。通过固相微萃取-气相色谱-质谱的风味分析技术，鉴定出嫩化鲍鱼热反应的主要特征风味化合物为吡嗪类物质。建立葡萄糖-甘氨酸的模型反应体系，采用稳定同位素示踪技术，发现烷基吡嗪与甲醛通过缩合反应生成乙烯基吡嗪，揭示了嫩化焙烤鲍鱼的特征风味化合物2-甲基-6-乙烯基吡嗪的形成机理。