yes it is necessary to use yeast to get puffiness, mesh like structure in bakery products such as bread , crackers and cakes .
Role of Yeast and types
Commercial yeast are of two types - Compressed yeast and Dry yeast
Compressed yeast - These can be further calssified as
* Breweries yeast - It acts on malt to give alcohol and carbon dioxide.
* Distillers yeast- It acts on molasses to give alcohol and carbon dioxide .
* Bakers yeast - It acts on sugar to produce carbon dioxide and alcohol. Carbon dioxide is the main by product.
Other features of compressed yeast
* Its available in cake form
* Its cheaper than dry yeast
* Moisture content is 80%
* Life of compressed yeast is 5 days
* Cell usage is 90-95%
* Its costlier than Compressed yeast
* Its is available in powder form
* Moisture is around 5%
* Life of dry yeast is more than one year
* Cell usage around 60%
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