- Reaction score
I am going to do a high gravity brew this weekend (OG = 1.106). I normally use liquid yeast and build up starters according to the calculated viability of the pack by the manufactured date. For this brew I am going to use S05 as I figured it will be easier and cheaper to get the required pitching rates then from liquid yeasts. I have a bit of confusion about the number of "viable" cells there are in a pack of dry yeast. In the past, and going by Mr Malty, I have figured that there are around 20 billion yeast cells per gram of dry yeast, so in a 11.5 g pack around 230 billion cells. However, I found the spec sheet on S05 from the fermentis website, see here. This states that there are 6 x 10^9 (6 billion) cells per gram. This would mean there are only around 69 billion cells in a 11.5 gram pack, that's much less then the supposed 100 billion in a fresh pack of liquid yeast. So what is correct? What fermentis are quoting seems too low, as too my knowledge the 11.5 g packs of dry yeast are meant to have much more yeast then the liquid. Unless of course I am reading this wrong.