High-sugar yeast is suitable for dough with sugar, and it still has a good fermentation performance even at 30% of sugar concentration; low-sugar yeast is suitable for making sugar-free or low-sugar fermented food like steamed bread and European staple bread because it has a good fermentation performance in sugar-free.
Why do you need to distinguish between high-sugar yeast and low-sugar yeast? It turns out that the raw materials such as sugar and salt in bread making will produce osmotic pressure. If the osmotic pressure is too high, the protoplasm and water in the yeast will seep out of the cell membrane, so that the yeast cannot maintain normal growth until death.
However, the tolerance of different yeasts to osmotic pressure varies greatly. Some yeasts have low sugar tolerance and are suitable for making sugar-free or low-sugar staple bread, steamed bread, etc.; some yeasts have high sugar tolerance and are suitable for making high sugar. dessert bread. When the amount of sugar added in the dough exceeds 7% (calculated as flour), it has an inhibitory effect on the activity of yeast, and when it is less than 7%, it has the effect of promoting fermentation. Generally, sucrose, glucose and fructose have greater osmotic pressure than maltose.
High-sugar yeast is suitable for making sweet bread, and even at 30% sugar concentration, the yeast still has good fermentation ability; low-sugar yeast is suitable for making fermented foods such as steamed bread and European staple bread with no sugar or little added sugar. In a word, the purpose of the distinction between high-sugar yeast and low-sugar yeast is to make yeast fully gas-producing in different environments, so that the dough can be fluffy and expanded to the greatest extent, and a better product can be produced.