Om jäst och mängder: http://www.mrmalty.com/pitching.php
Ett utdrag från avanstående länk om propagering:
"Greg Doss, Microbiologist/Brewer, with Wyeast Laboratories stated on the AHA TechTalk (08/31/2005) that approximately the following was true:
Pitching a Wyeast Activator pack gives the following results within 12 to 18 hours:
* 1 liter starter = about 150 billion cells
* 2 liter starter = about 200 billion cells
* 1 liter starter, then pitched into 4 liter starter = 400 billion cells
Practical experience with both products seems to indicate that these statements are at least in the ballpark and that good results can be had as long as a starter is made. However, one would think that you could go direct to 4 liters and get pretty close to the same 400 billion without doing the first 1 liter step. If you want lots of yeast, go 2 liters on the first step, then 20 liters (about 5 gallons) and repitch the yeast from that. Why don't 1 liter starters produce more yeast, even with a stir plate? There just isn't enough food to build that much yeast, no matter how much O2 and nutrient you add to it."
Starter FAQ: http://www.mrmalty.com/starter_faq.htm
Om ni inte har använt den innan så (pitching rate calculator): http://www.mrmalty.com/calc/calc.html