Head space in beer.

[Insomniac]

Just how important is headspace when brewing beer?
I've made a few meads so far but am just about to attempt my first wheat beer.

I've gone for a "Brewers Choice" kit to start me off, which claims to make 23 litres of beer. I don't have any 5 gallon carboys/buckets or do I have space to keep any, which is why I went with this kit as I can split the ingrediant easily to make 5 1 gallon batches.

My question comes from the fact that on actually measuring the amount of liquid my carboys hold (to the bottom of the neck) is 4.8 litres.

As far as I can tell I have 2 options, make 4 x 4.8 litre batches and then only have enough left for a 3.8 L batch which will have a huge head space.

Or make 5 x 4.6 litre batches which have a moderate head space but more than I would like!

Any advice on this?

 

[DregAddict]

Mostly you're going to be worried about O2 oxidizing your beer when it comes to headspace. If you only use the carboys for your primary fermentation then you should be OK because the actual fermentation process will push out any air and replace it with CO2.

Also, you won't want to make 4.8 liter, or even 4.6 liter batches in vessels that are only 4.8 liters to the bottom of the neck. Your krausen will most likely fill up the small amount of headspace and it will overflow your airlock. Honestly your best bet is to buy a cheap ale pail bucket or plastic carboy. They really don't take up much space. a 6 gallon carboy would certainly take up less space(in square footage) than 5 vessels that add up to 6 gallons.

 

[vitrael]

Head space is not bad while you are in primary, even if it's a 1 gallon carboy. The CO2 will displace the oxygen and your headspace will be inert to the beer.

 

[ayoungrad]

Depends on the yeast. True top-fermenting yeasts (often used with wheat beers) will require greater headspace - look on the manufacturers site for recommendations in regard to the particular strain - but true top-fermenting yeasts often require 1/3 of the total space for headspace. The risk is over-flow.

Some will say that if you use a blow-off tube(s) you can get away with less than 1/3 headspace.

 

[Insomniac]

Well, I currently have one spare cupboard with just enough space to fit my 3 small jars and height is a bit of an issue in there too!

Would starting them in primary with less liquid (say 4 L) and then topping up with fresh water after the ferment dies down help? Or would it negatively effect the beer? While i'm thinking, just how much difference would that extra .2 or water effect the taste? If I used ingedients for 4.6 but topped all the way to 4.8 would it just me horribly watery?

I can keep the beer fermenting at the bottom of it's temp range as well if that will cut down on any foam?

 

[Insomniac]

Just opened the kit and it comes with Munich yeast, which a quick google tells me is top fermenting. I also have some Nottingham lying around, but I guess the Munich will work better for a wheat beer?

 

[DregAddict]

Just opened the kit and it comes with Munich yeast, which a quick google tells me is top fermenting. I also have some Nottingham lying around, but I guess the Munich will work better for a wheat beer?

Yeah, both of those yeasts will be top fermenting and your krausen is likely to overflow if you don't give enough headspace. I'm not sure how the topping off idea would work. I do know that if you used all the ingredients but less water volume then you will have a higher than expected OG. This may cause your beer to reach a alcohol content that is too high for the yeast. You would have to crunch some numbers to figure out what your new OG would be and if the expected ABV exceeds healthy levels for your yeast.

Do you have to ferment in the cupboard? I honestly think a 7.5 gallon bucket or 6 gallon carboy is the way to go. You will only need ~2 square feet of floor space in any room of your house. If you don't have that then I don't know what to recommend.

 

[Insomniac]

There are places I could put one but not realy on a long term basis.
What about using up 2 of my jars, half filled (2.3 l) and then racking into a combined secondary?

 

[DregAddict]

There are places I could put one but not realy on a long term basis.
What about using up 2 of my jars, half filled (2.3 l) and then racking into a combined secondary?

OK, long term storage issues make sense. You could probably fill your jars with about 3.5 L pretty safely without much worry about overflow. I would lay down a towel or something in the cupboard just to be safe. And you're definitely going to want to calculate how much of the ingredients you'll need to use because I don't see a full batch being feasible with your setup.

Good luck. And if you get more info about topping off after fermentation, or if you end up giving that a try, then let us know how it turns out.

 

[Insomniac]

Thanks! I was always planning on only doing a part-sized batch, and have got a load of zip-lock bags for storing off the remaining ingredients.

I think for the first batch I will try filling with 3.6 L to start with, leaving 1 litre to be added later. Once the krausen is up to hight I can probably fill up a bit more to reduce any yeast stress from the high OG and then add in the rest once it's calmed down.

If that all goes horribly wrong I'll try something else on the second jars worth!
Cheers all!

 

[DregAddict]

Cool. Make sure any water you add is sterile, and try your best not to agitate the beer when you add it. This will limit O2 introduction.

 

[Insomniac]

Yup, I will be using bottled water for now, though should I bring it to a boil first anyway or will it be fine as is?

 

[DregAddict]

Boiling it would be a good idea, but if it's from an unopened bottle you should be fine. I have heard that boiling will help to drive off some of the O2 that is in bottled water, and since you'll be adding it post/during fermentation that might be a good idea. Especially since you'll only need a gallon or so for all your jars combined, so you won't have to wait too long for it to cool.

 

[Insomniac]

Cool, I have a plan then!
Cheers for the help, I'll try and reserect this thread with the results later!

 

[Insomniac]

Ok! I started my first batch just now. Split all the ingredients using 1/5th of everything (apart from the yeast, which i used about half of the 11g pack).

Used 3.5 litres of bottled Evian water.
One quick question, I have set this to go down to 17 degrees C, is this OK?
The Danstar site doesnt give a temp range for Munich, it just says it will complete in 4 days over 17 c. The instructions on the Brewers Choice kits says to ferment at 20c to 22c... should I be upping the temp to that sort of level? I was always under the impression temps that high can give nasty flavours, but I don't want to miss out on any esters that the recipe is relying on...

Cheers!

 

[Insomniac]

Well, after 2 days of bubbles I topped up with an extra 500ml water, bringing it to just below the curve, it gained a little extra krausen then stayed stable for a good 12 hours or so before deciding to jump out the airlock overnight! Not too much though, seems a bit happier after the clean up this morning.

 

[Insomniac]

First one has now been drunk it ended up more as a wheat ale as I fermented it cold and messed up the carbonation, but everyone liked it anyway. Second one is now in the fridge finishing its carb and a third I just started today but added some orange zest. All in all it seems to work and I'm happy with the results so far!

 

[unionrdr]

I know it's a little late now,but 23L is 6G to us. 19L is just a tiny hair over 5G.