Re: Making a starter on turbo yeast ?
- --- In firstname.lastname@example.org, Christopher Bedwell <eukanubaau@...> wrote:
>Your original query was to do with Turbo yeast packs and Ammonia smell.
> I should have elaborated, that turbo packets were a little old and therefore like an old smackpack - weak unless you give it some assistance... But that's not my question, either way...
When you open a T-pack prior to pitching, you will smell ammonia in it, because it is packaged with urea or another source of ammonia which is what yeast uses as nutrient (among other things).
However if you have pitched the pack into a full-sized wort, stirred it in, waited a half-hour or so. and THEN you still smell ammonia, the chances are pretty good the yeast is dead. Why? because it hasn't used any of the ammonia to begin multiplying. Hence the still strong ammonia smell.
The other thought is that if you have attempted to make a starter in a small amount of wort, you'll get the same smell. Because it's a LOT of ammonia in a small quantity of fluid.
I think that answers the question. What follows is for education purposes...
If some of the cells in a T-pack are old, damaged or dead, you're off to a bad start.
It's possible to grow out the viable cells from a T-pack (or any yeast source) but they will not act like a turbo. T-packs have just the right number and balance of yeast cells and nutrients to multiply quickly in a wort of the correct size. This ensures rapid start via complete innoculation and multiplying, and full attenuation.
Starters are different. There are two types.
1).. The first is a culture started from a very small number of good cells (sometimes even from a single cell). You need to step-feed the small starter with specific nutrients at just the right time as the multiplying yeast colony requires them. Then you add more wort as require to continue the food supply. When you have a big enough colony you can then pitch it as required.
This is a difficult task if you don't know the what or why of it all. Look up some of the info from Lalvin on yeast propagation and starters.
2)..The second type of starter uses a much larger number of starting cells, that are reconstituted from their dried state by adding warm water and a small amount of wort for food. This starter is ready to pitch after about 20 minutes.
As others have said, making starters from T-packs is not really do-able (or cost effective).