Question

Why do yeast survive in sugar solution but not in water?

Answer 1

They respire from the sugar solution and multiplies. There is no such food source to provide energy in water.The bud of yeastcell can be seen rapidly in sugar solution.


However, if oxygen is short (like in the middle of a ball of dough), then yeast canstill release energy from sugar, but in these conditions, its byproducts are alcohol and carbon dioxide. It is this carbon dioxide gas which makes the bubbles in dough (and therefore in bread), causing the dough to rise.