Clarification of fish odor components and suppression by cooking

鱼的气味被认为来自胺，如三甲胺。然而，其他化合物也有助于鱼的气味。本研究采用气相色谱-质谱联用技术（GC-MS）和气相色谱-嗅觉测量技术对鱼腥味物质进行分析，旨在阐明鱼腥味物质的结构、含量和形成机理。以沙丁鱼为试鱼，研究了抑制鱼腥味形成的烹饪方法。采用固相微萃取（SPME）纤维对鲜鱼和变质鱼的气味成分进行捕集。然后，将纤维注入气相色谱仪，并通过GC-MS和GC-olfactometry分析气味成分。在变质鱼中，只有当鱼样pH值大于9时，才能检测到三甲胺的存在，表明三甲胺不是鱼腥味的主要成分。在气相色谱-嗅觉仪中，发现一些羰基化合物和醇类具有令人不快的气味。尤其是2，3-戊二酮、己醛、1-戊烯-3-醇含量较高。由于这些化合物来源于脂质，因此认为用含有抗氧化成分的食物或调味品烹饪可以抑制鱼的气味。

Fish odor is thought to come from amines such as trimethylamine. However, other compounds also contribute to fish odor. In this research, fish odor components were analyzed by gas chromatography -mass spectrometry (GC-MS), and GC-olfactometry in order to clarify the structures, amounts, and formation mechanism of fish odor components. The cooking way to suppress the formation of fish odor was also developed.Sardine was used as the sample fish. The odor components of fresh or deteriorated fish were trapped by solid-phase microextraction (SPME) fiber. Then, the fiber was injected to GC and the odor components were analyzed by GC-MS and GC-olfactometry. In the deteriorated fish, trimethylamine was detected only when the pH of fish sample was higher than 9, suggesting that trimethylamine is not the key compound of fish odor. In GC-olfactometry some carbonyl compounds and alcohols were found to have unpleasant odor. Especially, 2,3-pentanedione, hexanal, 1-penten-3-ol were major. Since these compounds were derived from lipids, it is thought that cooking with foods or seasonings containing antioxidant components can suppress the fish odor.