Decanting yeast starters in fridge

[HumbleBrew]

I've never cold crashed and decanted my yeast starters before, but thought I'd give it a try for the beer I'm brewing this weekend. I don't use an airlock, just a piece of aluminum foil covering my starter jug. Do I need to worry about bacteria from the fridge getting in and infecting my starter? Has anyone had issues with this?

Thanks for your input.

 

[permo]

I don't decant in a fridge, but I cold crash mine in the fridge with aluminum foil over the top. I simple use a wire tie to keep it tight.

Then I remove from the fridge before I decant the wort. It's easier that way

 

[b-boy]

I use a 1 gallon jug with stopper with a hole in it covered with aluminum foil. I usually do a 3 L starter. I put it in the fridge a day or 2 before I brew. When I'm ready to pitch I decant the clear wort and use some wort from the boil pot to re-suspend the yeast cake. I swirl it up pretty good, then pitch it. Seems to work pretty well.

 

[HumbleBrew]

Guess I worded that a little funny huh? Would need a pretty big fridge to decant inside of

Cool, thanks.

 

[Biobrewer]

I would be careful cold crashing. It is a well known fact that fast temperature decrease (cold crashing) shocks most yeast and causes them to go dormant. While this is good to do if you are trying to drop yeast out of solution after fermentation, it may result in your yeast going into dormancy, resulting in longer lag phase upon pitching into fresh wort. In addition, you have to think about the fact that you are doubly shocking the yeast, since you cooled them down fast, and then are pitching them back into room temperature wort, which is another 20+ degree shift in the other direction.

My advice is if you have been pitching the whole starter as most do and had success, I would just keep doing that. I use a 2L starter made in a 1 gallon jug, 24-30 hours, stir plate, covered with foil. I pitch the whole thing, and my beer turns out great. If you are worried about volume and dilution, just reduce the final volume of your batch by the size of the starter, and it will be no different. I brew 6 gallon batches, but only collect enough wort for the boil to end up with 5.5 gallons. When I pitch my 2L starter, the volume goes back to 6gallons, and the gravity decreases slightly to what it should be for a 6 gallon batch.

#if it ain't broke, don't fix it

 

[DeafSmith]

#if it ain't broke, don't fix it

I have never had a problem cold crashing the starter. I use a foam stopper in my flask which allows air to enter but keeps bacteria out. I also keep a piece of aluminum foil loosely over the top of the flask while it is on the stir plate, and leave it there when I put the flask in the refrigerator. The next day, I take the flask out of the refrigerator and let it warm up slowly during the brew. I decant the liquid, keeping just enough to swirl the yeast to break up the cake, then pitch. No problems so far.

 

[Biobrewer]

I have never had a problem cold crashing the starter. I use a foam stopper in my flask which allows air to enter but keeps bacteria out. I also keep a piece of aluminum foil loosely over the top of the flask while it is on the stir plate, and leave it there when I put the flask in the refrigerator. The next day, I take the flask out of the refrigerator and let it warm up slowly during the brew. I decant the liquid, keeping just enough to swirl the yeast to break up the cake, then pitch. No problems so far.

I just know that it has been widely reported via experimentation that "crashing" a starter can actually harm it, unless cooled at a rate of 5F/day or slower. But if it works for you, that's good!

 

[b-boy]

I always let it warm up to room temp before I use it. It starts up pretty quickly.