Biab Keg Capasity

[Mitchjazz]

Hey all,

Just wondering if a 50 litre beer keg will be big enough for a double batch?? When i say double batch i use corney kegs (19liters each) and would like to fill 2 of them per batch. 38 liter total.

 

[mxd]

depends on the amount of grain, for me it wasn't, but if you sparge the bag it might be ok ?

The big issue is 40 ltrs into fermenter (38 out of), 2 ltr trub left in kettle, 5 ltr evaporation where at 47 ltrs so that will tough not to get a boil over.

Another option is dilute into the fermenter, so aim for 30 out of kettle, then 10 ltrs water + 30 ltrs wort into fermenter (I tried this as well and failed )

I ended up going for a 3V with 80 ltr keggle.

 

[beerdrinkingbob]

I think you might be a fraction short (only a guess based on my gear), but no real problem even if you are a little short.

Use the same amount of grain for a double and do a slightly higher gravity boil. It will increase you hop cost but for the gravity increase you would create you won't even notice.

Go the double mate, can't wait till i get my keggle going to do the same

 

[JestersDarts]

G'Day Mate -

If your ok to fiddle around with spreadsheets, this thread on biabrewer outlines how I get double batches out of my 45L kettle utilising post boil dilution, but maximises your vessel amounts along the way.

http://www.biabrewer.info/viewtopic.php?f=23&t=353

and spreadsheet here
View attachment The_Calculator_DOUBLE_BATCH__MY_SYSTEM1.1.xls
note the original spreadsheet and credit goes entirelyto biabrewer.info, i have only jigged cells to suit my system.

 

[argon]

Hey all,

Just wondering if a 50 litre beer keg will be big enough for a double batch?? When i say double batch i use corney kegs (19liters each) and would like to fill 2 of them per batch. 38 liter total.

right... long post but worth it;

Yep double batch BIAB can be done in a 50L keggle. I've done maybe a dozen double batch BIABs. TAs said before it's best to be done by adding top up water to the fermenter.

You do hit a bit of a ceiling as to how big you can make your beers for a double batch. I found that as the grain bill become larger (say over 9kg) 2 things would happen;

1. It becomes more difficult to get the bag out of the tun. Especially if you've cut the lid out, that is of a lesser diameter than the keg wall.

2. In my experience efficiency drops off pretty sharpish once you have a grain bill over 9kg. At 70% you can still make 2 kegs of 1050ish beer with that so it's not too bad.

For double BIABs, to get a reasonable efficiency you'll need to do a bit of sparging. I used an esky. Anything that's big enough to take your grain bag and enough water for the grain to rinse in is fine.

Here's what i used to do;
- Add 50L to the keggle and bing to 85C,
- Drain off 20L into my 44L esky, (eskys are good cause you need to hold the water at that temp till the mash is finished)
- Top up/adjust the keggle water to hit mash in temps, say 70C. (bit of cold water will get it right)
- Add grain then mash for 60 mins
- direct fire to hit mash out temp of 76C while stirring and sit for 10 mins
- I then pull the bag out (9kg is about as much as I can pull out of the keggle without too much hassle) dump it into the esky full of now 80C water for a dunk sparge.
- Give it a stir, leave for a bout 5-10 mins.
- Suspend the bag over the esky (by hand is ok... never found a skyhook very useful)
- Squeeze it till it pretty much stops dripping (no need to go overboard, just to stop dripping)
- dump the bag wherever
- Drain the contents of esky back into the keggle to hit approx 42L. It's touch and go for a little while, at this volume, just watch for boil overs
- then do your hop additions as per usual

If you're over your preboil volume, just boil off till you hit your desired mark.
Pretty easy really. The extra bit of faffing about is worth it, when you get to fill 2 kegs.

Employing this method I easily extract 34L to fill the 2 ex Fresh Wort Kit cubes (any cubes are fine as long as you squeeze the air out) This leaves behind about 2-3 litres of trub. I also calculate a top-up of 4 litres each to get 21L into the fermenter, gives me a pretty much spot on 19L into the keg, after polyclar and filtering.

Good luck with it... nothing like 2 kegs from on brewday
:icon_cheers:

 

[Mitchjazz]

Exactly the info i was after!! Brew day is this sunday so ill spend a few hours between now and then on my plan of attack. Still a bit unshore on recipies amounts. I got 25kgs of JW malt, 1kg dark malt ,1kgcrystal malt, 90g amarillo hop, 90g cascade hop, wirfloc tabs... Now to work on quantaties. Im also putting up some pics my of BIAB setup i put together last night ill post link on this thread once their up. Cheers for everyones help.

 

[mxd]

the other option is you can use it as HLT and Keggle, then use an esky for the MLT (can even use the bag in the esky)

 

[Mitchjazz]

the link if anyones interested..

http://www.aussiehomebrewer.com/forum/inde...m&album=714