Yeast Viability

[jlinz]

So, I'm making.a.2.5 gallon Scottish Ale. BeerSmith tells me that my wyeast 1728 yeast packaged on 10/29/15 has a.viability rate of 96%. So, no starter necessary. MrMalty tells me 52% will be viable and to use a litre starter. What to do?

 

[Big Monk]

You have a delta somewhere. What's your starting gravity?

 

[jlinz]

1.054

 

[jeremy0209]

Beersmith is telling me that your viability is 58.06%. There's a glitch in Beersmith that, if you put the manufacture date when you're selecting the yeast, it says 96% (it changes it to whatever today's date is)...but if you accept the defaults when you're selecting the yeast, then go back and edit the yeast (from the recipe) with the correct date, it gives you the actual viability.

 

[Big Monk]

I would think a 0.5L starter would be sufficient. I doubt you'll need more than 100B cells.

 

[jlinz]

Beersmith is telling me that your viability is 58.06%. There's a glitch in Beersmith that, if you put the manufacture date when you're selecting the yeast, it says 96% (it changes it to whatever today's date is)...but if you accept the defaults when you're selecting the yeast, then go back and edit the yeast (from the recipe) with the correct date, it gives you the actual viability.

Thanks for this. Didn't know about that glitch. Explains a lot.