I know there are two schools of thought on when to pitch starters, but for the sake of this topic I want to pitch my starter when it is at high kraeusen. I’m using two new vials of WLP001 to pitch into a 1.066 IPA (slightly underpitching I know, but I don’t have a large enough flask to do bigger and don’t want to buy another vial of yeast). I plan to make the starter using 200 grams of DME to equal a 2 Liter starter. Starter will be on a stir plate at around 67*F temperatures. Do you think it will be at high kraeusen within 24 hours? I use this technique from JZ’s Yeast book.
EDIT: And will it have enough time in 24 hrs to reproduce to close to the amount of yeast I’ll need?
When I do it the way you are proposing, I make the starter late into the evening the night before and pitch in the early evening the next day. So I guess it would be between 16-20 hours.
If the vials are fresh, you don’t really need to increase cell count. Assuming this is a 5-6 gal batch, you’d want around 250 billion cells versus around 200 billion in two vials.
To activate the yeast, I’d just boil and chill a liter or so of tail runnings and get that on the stir plate until you’re ready to pitch.
It was at high kraeusen at about 15 hrs. Perfect for when I wanted to pitch. However something weird happened that hasn’t happened to me before. I have a 2L flask and I usually just put foil loosely on top. Well it blew out the top. Does that mean my stir plate wasn’t working properly or maybe the stir bar wasn’t in the right spot?
WLP001 is a very vigorous fermenter.
Occaisionally, I’ve had the same result with 2L of starter in a 2L flask.
Some stir plates generate heat which warms the wort and that just increases the possibility that the wort will “boil” over. In this case, I found that a silicone pad between the stir plate and the flask will help.
You really need some headspace. I use a 2 gallon pail with lid and airlock for lager starters or larger starters or I will brew a smallish lightly hopped beer with the yeast straight up then harvest the yeast for the bigger batch. Then brew with the same yeast based on the timing of the batches (rotating through different beers and yeasts to avoid the need to make a lot of starters.)
That’s a really good idea. I wondered if people with large starters (> 2L) were using really big Erlenmeyer flasks and how they managed that much volume. Thanks for the idea.
Add a few drops of fermcap to your flask and you can get away with making a full volume starter having relatively little headspace even with the most vigorous of yeasts.