Both supplementations of glycerol and fructose had influenced
redox reaction balance. Final concentrations of acetate and propanediol
(Table 2) were obviously increased respectively from Ca. 17 g/L to Ca.
19 g/L and from 0.405 g/L to Ca. 7 g/L, with an increase of glycerol
supplementation. 5 g/L of glycerol supplementation had promoted
final lactate production from Ca. 18 g/L to 20 g/L, but 10 g/L of glycerol
supplementation suppressed final lactate concentration, down to
Ca. 17 g/L. The same phenomena were also observed in the trend of
final ethanol concentrations. More ethanol was produced under 5 g/L
glycerol supplementations.
The final concentrations ofmannitol had a positive relationshipwith
supplementation concentrations of fructose. Soy-yogurt with fructose
supplementation produced 108% to 123% more mannitol than control.
When glycerol was fixed at one level, the increase of fructose supplementation
reduced final concentrations of lactate (5%), acetate (1%),
and ethanol (10%), but it raised the concentrations of propanediol (8%).