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BACKGROUND The physiological metabolism of yeast has a significant impact on the quality of fermentation products, this research was to clarify the yeast metabolism in response to a changing glucose content environment, especially in fermentation products, the change of carbon flow rate, antioxidant status, and yeast enzyme activity. RESULTS The yeast in 0 g/L glucose level was subjected to carbon starvation stress, cell growth retarded and cell proliferation was significantly inadequate; in the logarithmic growth stage of yeast at 30 g/L glucose level, carbon source mainly flowed to tricarboxylic acid cycle and pentose phosphate metabolism, cell division, proliferation, and cell growth speeded. In later logarithmic growth period and stable period, carbon flowed into glycerol and trehalose metabolism, to cope with the environmental stress; the yeast in 60 g/L and 150 g/L glucose levels faced high glucose stress at the beginning, the content of reactive oxygen increased, malondialdehyde content increased, cell damage was reduced through the regulation of superoxide dismutase (SOD) and catalase (CAT) enzyme activities, and most of the carbon flowed into the metabolic pathway of ethanol, glycerol, and trehalose to cope with high glucose stress, the pentose phosphate pathway showed a large late influx, and nicotinamide adenine dinucleotide phosphate (NADPH) also started to increase rapidly after 24 h. CONCLUSION Yeast was stressed in a high-sugar environment and ensured the activity of yeast by preferentially increasing the metabolic intensity of trehalose, glycerol and glycolytic metabolism, weakening TCA metabolism, and first weakening and then increasing pentose phosphate metabolism. This article is protected by copyright. All rights reserved.