TY - JOUR T1 - Effect of Fermentation Temperature and Culture Medium on Glycerol and Ethanol during Wine Fermentation JF - American Journal of Enology and Viticulture JO - Am. J. Enol. Vitic. DO - 10.5344/ajev.2011.11067 SP - ajev.2011.11067 AU - Gang Du AU - Jicheng Zhan AU - Jingyuan Li AU - Yiling You AU - Yu Zhao AU - Weidong Huang Y1 - 2011/11/11 UR - http://www.ajevonline.org/content/early/2011/11/09/ajev.2011.11067.abstract N2 - Yeast strain BH8, which exhibited significant difference with nine other yeast strains studied for glycerol production, was selected to investigate the effect of fermentation temperature (13 °C and 25 °C) and culture medium (synthetic medium and grape must) on fermentation kinetics, yeast growth, and the synthesis of glycerol and ethanol at three different stages of wine fermentation. Yeast viability was better at 13°C than at 25°C in both growth media, and the more complex grape must enabled yeast cells to reach a higher-population density. The accumulation of glycerol, glycerol-3-phosphate dehydrogenase (GPD) activity and the level of expression of the GPD1 gene were highest in the initial stages of fermentation, which potentially counteracted the hyperosmotic stress caused by the high concentration of sugar in the media. More glycerol was produced during fermentation at 25°C than at 13°C and in grape must compared to the synthetic medium at both temperatures. Ethanol production was mainly affected by the fermentation temperature. More ethanol was produced at 13°C than at 25°C, with lower the expression of the ADH1 gene and the level of ADH activity. The expression of the HSP104 and ALD6 genes was induced by ethanol stress in the final stages of fermentation. The amount of glycerol produced was not correlated to the production of acetic acid or succinic acid. ER -