Applications of Salt Stressed Baker's Yeast in the Bread Making Process

The length of time baker's yeast was immersed in a salt solution, salt concentrationentration and immersion before and after other ingredients were added varied according to a central composite response surface design. The effect on trehalose, glycerol, gas production of dough, specific volume and firmness of bread was explored. The results of this study showed baker’s yeast stress induced trehalose increased with salt concentration in direct (immersion in salt water prior adding other ingredients) (p<0.01) and indirect (salt water added the same time as other ingredients) (p<0.001) salt stressed baker’s yeast but decreased with stress time (p<0.001) in indirect salt stress. Direct salt stressed baker’s yeasts had approximately double the trehalose of indirect salt stressed baker’s yeast. Glycerol increased with time (p<0.001) for both types of stresses but decreased with salt concentration (p<0.001) when indirectly salt stressed. The indirect stress had about 8-fold more glycerol than direct salt stress. It had a greater amount of gas production from the dough of indirect salt stress than direct salt stress. A significantly larger specific volume and softer consistency were noted in the indirect salt stressed baker’s yeast. This may be because of more glycerol in indirect salt stress yeast than that of direct salt stress yeast. This might be useful for applications of salt stressed baker’s yeast in the bread making process.