Clarification of fish odor components and suppression by cooking

鱼腥味被认为来自三甲胺等胺类物质。然而，其他化合物也会导致鱼腥味。本研究采用气相色谱-质谱法(GC-MS)和气相色谱-嗅觉法(GC-OFEMS)对鱼腥味成分进行了分析，旨在阐明鱼腥味成分的结构、含量和形成机理。还开发了抑制鱼腥味形成的烹饪方法。以沙丁鱼为样品。采用固相微萃取(SPME)纤维对鲜鱼或变质鱼的气味成分进行捕获。然后，将纤维注入气相色谱，用GC-MS和GC-嗅觉仪分析其气味成分。在变质鱼中，只有当鱼样的pH值高于9时才能检测到三甲胺，这表明三甲胺不是鱼腥味的关键成分。在GC-嗅觉分析中，发现一些羰基化合物和醇类化合物有难闻的气味。其中以2，3-戊二酮、己醛、1-戊烯-3-醇为主。由于这些化合物是从脂类中提取出来的，所以人们认为用含有抗氧化剂成分的食物或调味品烹饪可以抑制鱼腥味。

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.