If subdivided, there are different classifications such as high sugar tolerance, freezing tolerance, etc., which are suitable for different bread recipes or techniques.
There is also a more classic classification, which only belongs to the professional field and generally needs to be purchased through special channels.
First, fresh yeast: unstable activity, low fermentation capacity.
Not resistant to storage, it needs to be stored at a low temperature of 0℃~4℃, and it can be stored around, otherwise it is easy to rot and autolysis.
Usage: generally activate with warm water before use.
Second, active dry yeast: it is more convenient to use than fresh yeast.
The activity is stable and the fermentation power is high.
It is forbidden to store at low temperature, but it can be stored at room temperature for about one year.
Warm water activation is required before use.
Disadvantages: Higher cost.
Instant active dry yeast: vacuum sealed packaging, which is very hard after packaging.
High activity
The activity is particularly stable, and it can be stored for three years without opening.
The fermentation speed is fast, which greatly shortens the fermentation time.
The cost and price are high, but due to its high fermentation power, its activity is stable and its usage is small.
When in use, warm water is not needed for activation, but cold water cannot be directly contacted, otherwise the yeast activity will be seriously affected.
Each has its own advantages and disadvantages, and the usage of these three yeasts:
The conversion relationship of usage among the three yeasts: fresh yeast: active dry yeast: instant active dry yeast =1:0.5: 0.3.
Therefore, comprehensive factors should be considered in practical use, including formula, technology, cost, convenience of procurement and so on.