Using Wort for Starter

I would like to try using my cooled wort as starter material, but that means the rest of the wort has to wait a day or so for the yeast.  Any obvious pitfalls with this idea?  I can control the temperature.

Yeah. Go ahead and pitch your yeast if you made the brew. Reserve wort for next time and make your starter in advance.

Good luck.

This time, not next time.  I’m talking about as soon as the wort cools to room temperature, putting a quart or more into a flask, put it on a stir plate, and add the yeast.  The rest of the wort will wait in the primary carboy, air locked, at fermentation temperature, until the starter is ready.

Go ahead and try it. My opinion is that “fermentation temperature” is still within the danger-zone for bacteria. You’ll probably be fine though. Not many of us will advise you to do it as a regular technique.

I’ve considered doing this to get the yeast up and running after I’ve already built up a good population through stepped up starters.  But I haven’t done it yet and if I did it’d only be a short wait to get to high krausen.  I’ve let my wort sit overnight (maybe 12 hours or so) a couple of times (because I forgot to crash my starter early enough) without any problems.  Like Euge says letting it sit at fermentation temp for a couple of days might be a bit on the risky side.

If you want to try this and are using a fridge/freezer and temp control you could bring the wort down to refrigeration temperatures quickly after it’s transferred to the fermenter and then let it come back up to pitching temp when you’re ready.  That would help retard the bacteria growth.

Thanks guys for the tips and insight.  I think I’ll stick with DME started pre-boil.  This Forum makes AHA membership worthwhile all by itself.

Every three of four brews, I’ll adjust recipe to 11 gal, instead of 10, and fill four mason jars of wort, pressure cook them, and stick them in the fridge.  That’s what I use for starters.

So far, it’s all gone great.  The IPA have fermenting now used a stepped up starter begining with just one pack of 1056 for ten gallons.  I’ll find out next week how well that worked…

This is something I definitely want to start doing.  Need to get myself a pressure cooker first though.

One of the Brewstrong episodes described this process.  It’s not my original thought.

Why not just freeze it instead of canning it? If you can it you don’t need to put it in the fridge.

^^^^^^^This is what I Do.

me too - an old club soda bottle does the trick!

Good question, I don’t have a good answer.

I always thought it was a question of the wort being in a sanitized environment (freezer) versus sterile (canned).

Well, you’re supposed to boil it again.

I think that depends entirely on your level of bravery.  If the wort was boiled and then put into a sanitized bottle or jar, then refrigerated, don’t you think you could add it right to your yeast when you need to make a starter?
I saved some almost boiling hot low-gravity wort in sanitized 12 ounce bottles which I capped and refrigerated.  It makes for an easy, no boil starter.

The attraction to me of canning would be having sterile wort on hand for quickly making starters without boiling.  I don’t think I’m brave enough to store in the freezer and not boil it before using it in a starter.

The concern is botulism.  Boiling or freezing alone won’t kill the spores that cause it.  That’s why people use a pressure cooker to can food (boiling temperature is higher under pressure, high enough to kill the spores).

That said, I’m not sure I share the concern.  We don’t worry about spores in finished beer, presumably because of the lower pH and the alcohol.  So if this wort eventually becomes finished beer, what’s the danger?  Maybe that the spore count will be too great by then for the pH and alcohol to bring it down to the (very low) level tolerable by humans …

That is the concern.  The low pH and alcohol will prevent growth of any more toxin but it has no affect on what might already be present.  If you’re going to be using the wort within a very short time, then freezing is probably save as there wouldn’t be enough time for toxin growth.  But if you’re going to be saving it for any significant amount of time, pressure canning is the way to go as that guarantees that there’re no spores to generate toxin.

For me, I prefer to play it safe and pressure can all my starter wort.  It really takes very little effort.

It is Botulinum toxin, not so much the spores, that we should be concerned about when talking about food-borne botulism.
For food safety reasons, I’d recommend boiling your starter wort (and cooling it down to pitching temps) before pitching the yeast.
Regardless of storage method (refrigeration vs freezing, pressure cooked mason jars vs sanitized plastic jugs, etc.), boiling the starter wort will inactivate any botulinum toxin that may have been produced during storage.  And boiling is an easy way to sanitize the flask and aluminum foil covering, as well.