γ-Glutamyl peptides are known to impart a kokumi sensation and increase the palatability of food. To compare the γ-glutamyl peptides produced by different yeasts, Saccharomyces cerevisiae and Debaryomyces hansenii were cultured in a conventional medium (YPG) and a medium composed of porcine hemoglobin hydrolysates (YHG) for six days. Quantification of γ-glutamyl peptides as well as analysis of yeast growth and γ-glutamyltransferase (GGT) activity were carried out. Results showed that both strains could form a range of γ-glutamyl dipeptides and glutathione in either medium. The total concentration of dipeptides and the concentration of glutathione in each medium showed an upward trend over fermentation time. Compared with yeast species, medium composition had a greater impact on the formation of γ-glutamyl dipeptides. During most of the fermentation period, D. hansenii produced more γ-glutamyl dipeptides (reaching a maximum of 2.395 μM on day 6 in YHG), while S. cerevisiae generated more glutathione (reaching a maximum of 13.465 μM on day 5 in YHG). In addition, D. hansenii showed higher GGT activity than S. cerevisiae in the latter half of fermentation. This study illustrates the influence of growth medium and the crucial choice of yeast species for obtaining target γ-glutamyl peptides for kokumi sensation.

众所周知，γ-谷氨酰肽可赋予浓郁的感觉并增加食物的适口性。比较不同酵母、 Saccharomyces cerevisiae和Debaryomyces hansenii产生的 γ-谷氨酰肽在常规培养基 (YPG) 和由猪血红蛋白水解物 (YHG) 组成的培养基中培养 6 天。进行了γ-谷氨酰肽的定量以及酵母生长和γ-谷氨酰转移酶（GGT）活性的分析。结果表明，两种菌株均可在任一培养基中形成一系列γ-谷氨酰二肽和谷胱甘肽。各培养基中二肽总浓度和谷胱甘肽浓度随发酵时间呈上升趋势。与酵母菌种相比，培养基组成对γ-谷氨酰二肽形成的影响更大。在大部分发酵期间，D. hansenii产生更多的 γ-谷氨酰二肽（在 YHG 第 6 天达到最大值 2.395 μM），而S. cerevisiae产生更多的谷胱甘肽（在 YHG 第 5 天达到最大值 13.465 μM）。此外，D. hansenii在发酵后半期表现出比S. cerevisiae更高的GGT活性。本研究说明了生长培养基的影响以及酵母种类的关键选择对于获得用于 kokumi 感觉的目标 γ-谷氨酰肽。