Membership questions? Log in issues? Email info@brewersassociation.org

Author Topic: Bottling a blueberry wheat beer  (Read 1228 times)

Offline Wayne Baker

  • 1st Kit
  • *
  • Posts: 3
Bottling a blueberry wheat beer
« on: August 08, 2021, 06:15:40 pm »
I used some potassium metabisulfate to kill my beer yeast two days prior to racking my wheat beer on 3lbs of blueberry purée.  I did not want the sugars in the purée to ferment.  My question is how much additional yeast do I pitch with the priming sugar to carbonate the beer?

Offline majorvices

  • Global Moderator
  • I must live here
  • *****
  • Posts: 11326
  • Polka. If its too loud you're too young.
Re: Bottling a blueberry wheat beer
« Reply #1 on: August 09, 2021, 05:30:13 am »
If you killed the yeast to stop the fermentation, but then you add more yeast to carbonate you will surely end up having bottle bombs since the yeast won't know when to stop. In brewing we generally let our beer ferment out to completion.

One option is to keg it and force carbonate it.

Online denny

  • Administrator
  • Retired with too much time on my hands
  • *****
  • Posts: 27092
  • Noti OR [1991.4, 287.6deg] AR
    • Dennybrew
Re: Bottling a blueberry wheat beer
« Reply #2 on: August 09, 2021, 08:35:42 am »
I used some potassium metabisulfate to kill my beer yeast two days prior to racking my wheat beer on 3lbs of blueberry purée.  I did not want the sugars in the purée to ferment.  My question is how much additional yeast do I pitch with the priming sugar to carbonate the beer?

AFAIK, that will only slow the yeast, not kill it.  You need to use sorbate also.
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

"The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts." - Bertrand Russell

Offline joe_meadmaker

  • Brewer
  • ****
  • Posts: 399
Re: Bottling a blueberry wheat beer
« Reply #3 on: August 09, 2021, 08:00:31 pm »
As denny mentioned, to completely stabilize the beer you would need to use metabisulfite and sorbate.  That said, metabisulfite by itself will make a pretty unwelcoming environment for the yeast.  So if you were near (or at) the end of fermentation, that may have been enough.  But as majorvices said, if you add new yeast, those two chemicals aren't going to do a thing.  The new yeast will get to work and ferment any available sugars, including what's in the puree.

You've got a few variables going on for bottle conditioning, but this is what I would probably try.  From what I can find, blueberries are around 10% sugar.  I would assume that puree is approximately the same, unless it indicated on the packaging that something else had been added.  So assume that 10% of the puree weight is going to be sugars that will be fermented in the bottle.  Make sure you subtract that weight from the amount of priming sugar you add and hopefully things will be close to what is needed for carbonation.  Also please keep in mind that this is only a hypothetical.  It's not something I've actually done.

I'm not sure on the yeast.  Are you using a dry yeast?

Offline majorvices

  • Global Moderator
  • I must live here
  • *****
  • Posts: 11326
  • Polka. If its too loud you're too young.
Re: Bottling a blueberry wheat beer
« Reply #4 on: August 10, 2021, 05:12:03 am »
This trick will be naturally conditioning a beer in which fermentation was purposely stopped. The only way I can think of is force carbonating. If there is a other trickI'd love to know about it.

Offline joe_meadmaker

  • Brewer
  • ****
  • Posts: 399
Re: Bottling a blueberry wheat beer
« Reply #5 on: August 10, 2021, 08:50:20 pm »
I agree.  A forced carbonation would definitely be the best way to go.

The OP mentioned adding additional yeast.  The safest option would probably be to add it to the batch (possible with a small amount of sugar to help get things going) and let it finish out the fermentation.  Then priming sugar and bottling could be done normally and the beer should be fine.

Offline BrewNerd

  • Cellarman
  • **
  • Posts: 74
Re: Bottling a blueberry wheat beer
« Reply #6 on: August 14, 2021, 04:57:56 pm »
Granted I've only made 10 batches so far and read a dozen or so books.. but that's the first time I've heard of anyone wanting to stop a fermentation by purposefully killing their yeast. Just one more way to regulate a fermentation.

I prefer to kill my yeast the old fashioned way: through stupidity.

Offline majorvices

  • Global Moderator
  • I must live here
  • *****
  • Posts: 11326
  • Polka. If its too loud you're too young.
Re: Bottling a blueberry wheat beer
« Reply #7 on: August 17, 2021, 07:41:40 am »
Granted I've only made 10 batches so far and read a dozen or so books.. but that's the first time I've heard of anyone wanting to stop a fermentation by purposefully killing their yeast. Just one more way to regulate a fermentation.

I prefer to kill my yeast the old fashioned way: through stupidity.

It's common in wine making. Very rare in beer brewing. Usually when someone back sweetens a beer it is with unfermentable sugar.

Offline joe_meadmaker

  • Brewer
  • ****
  • Posts: 399
Re: Bottling a blueberry wheat beer
« Reply #8 on: August 20, 2021, 07:52:49 pm »
To add clarification, potassium (or sodium) metabisulfite does not kill yeast.  Neither this or potassium sorbate will stop a fully active fermentation.  The purpose of adding a sulfite is to prevent the growth of wild yeast strains, bacteria, etc.  It also works as an antioxidant.  Sulfites are usually used as a preservative once fermentation is complete, not as a method to stop fermentation.  Potassium sorbate is the compound that can be used to prevent fermentation from starting back up.  But again, this isn't intended to stop an active fermentation or kill yeast.  What it does is prevent yeast from growing and multiplying.  So if you add potassium sorbate and then backsweeten, there may still be a very small amount of fermentation that occurs but it will be essentially insignificant.

As majorvices mentioned, these two chemicals are much more often used in wine and mead.  I've only used them in beer once.  I had a brown ale that I wanted to backsweeten with honey, so I used metabisulfite and sorbate to stabilize the beer, stirred in the honey, and kegged it.  The keg was refrigerated so the fermentation wouldn't have picked back up, but I was planning to bottle part of the batch and didn't want there to be problems if a bottle warmed back up to room temperature.  The process of stabilizing and backsweetening works fine for beer, but it's not something you really hear about.