Ueda Shuji, Sasaki Ryo, Nakabayashi Rio, Yamanoue Minoru, Sirai Yasuhito, Iwamoto Eiji
Department of Agrobioscience, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Hyogo, Japan.
Food Oil and Fat Research Laboratory, Miyoshi Oil & Fat Co., Ltd., Tokyo 124-8510, Japan.
Metabolites. 2021 Mar 29;11(4):203. doi: 10.3390/metabo11040203.
The meat from Japanese Black cattle (Japanese Wagyu) is finely marbled and exhibits a rich and sweet aroma known as Wagyu beef aroma. To clarify the key metabolites involved in the aroma, we analyzed the correlation between lactone and lipid composition in Japanese Black cattle. Using gas chromatography-olfactometry, we identified 39 characteristic odorants of the intermuscular fat. Seven characteristic lactones considered to be involved in Wagyu beef aroma were quantified and compared in the marbled area and intermuscular fat using a stable isotope dilution assay. Among them, γ-hexalactone was the only lactone whose level was significantly higher in the marbled area. To explore the lipid species involved in lactone formation, we analyzed samples with different aroma characteristics. Liquid chromatography-mass spectrometry revealed eight lipid classes and showed significant differences in triacylglycerides (TAGs). To determine the molecular species of TAGs, we performed high-performance liquid chromatography analysis and identified 14 TAG species. However, these analyses showed that seven lactones had a low correlation with the TAGs. However, γ-hexalactone showed a positive correlation with linoleic acid. This study suggests that lipid composition affects the characteristic lactone profile involved in the Wagyu beef aroma.
日本黑牛（日本和牛）的肉有着精致的大理石花纹，散发着浓郁而甜美的香气，即所谓的和牛肉香。为了阐明与这种香气相关的关键代谢物，我们分析了日本黑牛内酯与脂质组成之间的相关性。通过气相色谱 - 嗅觉测量法，我们鉴定出了肌间脂肪的39种特征性气味物质。使用稳定同位素稀释分析法对大理石花纹区域和肌间脂肪中7种被认为与和牛肉香有关的特征性内酯进行了定量和比较。其中，γ - 己内酯是唯一在大理石花纹区域含量显著更高的内酯。为了探究参与内酯形成的脂质种类，我们分析了具有不同香气特征的样本。液相色谱 - 质谱分析揭示了8种脂质类别，并显示出三酰甘油（TAGs）存在显著差异。为了确定TAGs的分子种类，我们进行了高效液相色谱分析并鉴定出14种TAGs分子种类。然而，这些分析表明7种内酯与TAGs的相关性较低。不过，γ - 己内酯与亚油酸呈正相关。本研究表明，脂质组成会影响和牛肉香中特征性内酯的分布情况。
