Head space + carbonation

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jbeins1
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Head space + carbonation

Post by jbeins1 »

Hi! I am on my second batch of cider. This time I am going for a guava cider with guava juice and apple. I am excited for the batch, but I want this one to turn out well. A couple of things I had questions about:

1. I have read that having a lot of head space in the brewer is a bad thing. I am starting out with the brew demon 2 gal. container that could probably hold closer to 3 gallons, leaving me about 4" of head space. I have just read that having a lot of head space in the container can be a bad thing. Why is that? And what are the things to look for? The last cider I did (the basic from Brew Demon) turned out just fine with no funky flavors from that much head space.

2. Last batch did not carbonate well. I had a few bottles do OK, but not nearly the carbonation I was hoping for. I used coopers 25 oz PET brown bottles and added 2 tsp table sugar to each bottle. I let them sit at room temp for 2 weeks. Should I be adding the sugar to the entire batch before bottling? What volume of CO2 should I be going for in a cider if I use the carbonation calculators online? Any preference on carbonation calculators?

I really appreciate the help. I am looking forward to this batch, and I want it to turn out!
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mashani
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Re: Head space + carbonation

Post by mashani »

4" of head space is nothing. As in "not too much headspace". Some beer yeast can fill a full 1/3rd of the volume of your fermenter with krausen. So you either leave enough headspace for that (IE a full gallon worth in a 3 gallon fermenter), or you have to use a blowoff tube which ultimately means less beer. I'd rather have more beer, so I go with more headspace!

Anyways, it is really only a bad thing if you are leaving the beer or cider in there for a very long time. IE if you were to put it into a secondary fermenter to clear after 2-3 weeks in the primary, then in that secondary fermenter you want as little headspace as possible. This is because the beer/cider is no longer producing CO2 and displacing the oxygen. So to displace it, you have to do it with the liquid volume up front. It is mostly about preventing oxygen exposure, both due to oxidation, and also beer infecting bugs that happen to work better in the presence of oxygen. (or in some cases at least look like they are working better to the naked eye, IE pellicle forming, although the fact is they could still be in there, in which case people get the random bottle gushers or such later because they never noticed a pellicle forming). But for at least 10-14 days, enough CO2 should be coming out of solution to leave a little CO2 blanket in your primary fermenter as long as you aren't always fiddling with it / shaking it around.

I don't know anything about proper CO2 volumes for cider, but this is a good calculator if you want to start to batch prime.

https://www.brewersfriend.com/beer-priming-calculator/

The best way to batch prime is to use a separate fermenter or bottling bucket, and put the sugar in a boiled and cooled solution into the bottom, and then rack your beer into that container. This gets it all mixed in well. If it doesn't get mixed in well you can get inconsistent results as well.

If you got random results with bottle priming, it's either because your measuring wasn't accurate - measuring by volume is like this, little pockets of air or what not can make a big difference - measuring by weight is always better... OR that some of the bottles didn't get as good of a seal as others. To get somewhat consistent and accurate "measuring" results by volume, you have to "shake and scrape", IE overfill the measuring device, then give it a shake to try to settle the contents, and then scrape it level to the top of the measure with a flat side of a knife or similar. If for some reason I was measuring vs. weighing when baking that's how I would treat flour.

When using the PETs, I suggest you bottle, and cap as you did. But then walk away for ~30 minutes, and come back and give each cap another twist then. You will be surprised and amazed to find that some of them will torque down more, even though they seemed tight when you did it the first time.

2.5g Dominos Dots sugar cubes can work well btw. They aren't going to be 100% consistent, but will give decent results 99% of the time. For your sized bottles, 2 of them should be about right. The 2.5g ones are the ones that come 198 in a box. If nothing else they are a hella lot easier to deal with then measuring sugar in a tsp and pouring it in and they are much less expensive then beer specific priming sugar lozenges like Coopers sells.
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