There's been some discussion of vitamin B12 in recent posts. A generally
accepted assumption is that nutritional yeast is a source of B12. A little
over a year ago, someone on the Fat-Free list mentioned that all
nutritional yeasts are not fortified with B12, naming Red Star T-6635+ as
one source. I asked my HFS if theirs had B12. "Absolutely", I was told. I
asked to see the label of on the 50 pound sack they use for their bulk
sales, and there was no mention of B12 on it. After calling Red Star, I
received a data sheet for all their nutritional yeasts. Of Red Star's
yeasts, only T-6635+ contains a significant amount of B12 (0.5 mcg per
gram). When I brought this to the attention of the general manager of the
HFS, he immediately ordered the T-6635+ for all future shipments. While I
had no immediate concern about a B12 deficiency, I had been consuming a
nutritional yeast which added no B12 to my system.

I noticed that the B12 fortified yeast was a much darker golden color than
the ivory color of the the unfortified yeast, but that may vary from lot to
lot.

For what it's worth, the information sheet says that Red Star's primary
grown nutritional yeasts are from a pure strain of Saccharomyces cervisiae,
grown in a mixture of cane and beet molasses. (For those who remember their
Latin, cervisiae would indicate a beer base.)

A heaping tablespoon of nutritional yeast is about 8 grams. (4 mcg B12)
This yeast is 4.7% fat, 35% carbohydrate and 52% protein, the rest is
nitrogen and moisture. There are 2.8 calories of energy per gram.

The complete nutritional analysis of T-6635+, including the specific
amounts of each amino acid, is available from Universal Foods Corp., 433
East Michigan Street, Milwaukee, WI 53201. (414) 271-1920