Nancy,
As I understand it, nutritional yeast is grown on a molasses base;
brewers's yeast is a by-product from beer (hence the bitter taste).
Red Star T6635 is the brand that I see most often. Most HFS
have it available in bulk, but you can get it mail order from a variety
of sources. It is fortified w/ B12 and provides many other nutrients.
I have yet to use it as a main ingredient, but often add it to cereals,
pancake, and sauces.
Happy hunting!
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