Division of Shochu Fermentation Technology, Education and Research Center for Fermentation Studies, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima City 890-0065, Japan.
Food Chem. 2017 Jun 1;224:398-406. doi: 10.1016/j.foodchem.2016.12.005. Epub 2016 Dec 7.
Red koji, which refers the solid culture grown koji mold on the steamed rice, is one of the ingredients of Asian fermented foods including the Japanese spirit shochu. This study was aimed at elucidating the characteristic flavor and key volatile compounds of red koji-shochu as well as the mechanism of their formation. Sensory evaluation showed that red koji-shochu has the distinctive flavors cheese, sour, milky, and oily. Fifteen key volatile compounds of red koji-shochu were identified by gas chromatography-mass spectrometry and high-performance liquid chromatography, and by comparison between red koji-shochu and white koji-shochu, as another typical shochu. The mash analysis revealed that ketone compounds and short-chain acids derive from red koji. Furthermore, although other key compounds were produced by yeast, it is highly likely that their concentrations were affected directly or indirectly by the high activities of protease and lipase in red koji.
红曲，是指在蒸熟的米饭上生长的固体培养曲霉菌，是包括日本清酒在内的亚洲发酵食品的成分之一。本研究旨在阐明红曲清酒的特征风味和关键挥发性化合物，以及它们形成的机制。感官评价表明，红曲清酒具有奶酪、酸、乳香和油腻的独特风味。通过气相色谱-质谱联用和高效液相色谱法，从红曲清酒中鉴定出 15 种关键挥发性化合物，并与另一种典型的清酒——白曲清酒进行比较。醪液分析表明，酮类化合物和短链酸来源于红曲。此外，尽管其他关键化合物是由酵母产生的，但它们的浓度很可能直接或间接地受到红曲中蛋白酶和脂肪酶高活性的影响。
