High Gravity Biab

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jzani

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Hi all

I have recently purchased a 40L Urn and made myself a BIAB bag (at least, I told SWMBO what to do) and made my first All Grain (care of Dr Smurto :icon_cheers:) which is waiting to be bottled. For my next brew, I had been planning to experiment with a small batch of something different, and have found a recipe for a La Trappe Quadrupel clone which sounds ideal.

However, the Podcasts about BIAB on the Brewers' Network and BeerSmith blog have said that one of the limitations about BIAB is with high gravity brews, but I haven't been able to find out any further info on this. If anyone else has tried a high gravity BIAB recipe and can expand on the potential pitfalls, I might be able to avoid them, or rethink the recipe altogether.

Thoughts and opinions much appreciated.
:beer:

Juzzy
 
With high gravity beers couldn't you BIAB with 3/4 mash volume then sparge the remaining 1/4 to get better efficiency?
 
The problem is with physically fitting 10kg+ of grain and the 35-40L of water into your pot, it just won't fit into a 40L pot. Another problem is with lower effeciency, since you have more grain, it will retain more of the sugar, though you can reduce this somewhat with a sparge step.

I've had problems fitting 7.5kg (1.068 OG) of grain and 37L water into my 50L pot , I had to reserve 1-2 L of my strike water to fit it in comfortably, so I was able to stir it around without it spilling out.


Mashing in with less water and sparging to reach boil volume is one solution, another is to replace some of the base malt with DME or if you're doing a belgian they usually make up the OG with a % of sugar.
 
I have produced big beers BIAB style, mainly with the use of 2 grain bags in together, however i use a 60L pot.
I made a 11% belgian ale, which had about a 11kg grain bill, so i divided it into 2 bags and mashed together etc, they were easier to lift then.
having not used a 40L urn, i cant comment as to wether it will do it in one go, or rather a couple of runs.
 
So, if I am only planning a half (10L) batch, which involves about 5kg of grain, all I need to do is boil with about 9-10L (2:1 ratio??) and sparge with about 5L of (hotter??) water and there should be no issues?

From what you guys have said, the only problems with high gravity BIAB will arise when I am doing big(ger) batches?

Thanks for replies.
 
Plug your numbers into the volume spreadsheet here

Link not working on BIABrewer, but I got these volumes off BeerSmith, so I will stick with them.


Working link to the spreadsheet would be good, though (says I don't have permission to access file).
 
Generally you need to joint BIABrewer. info to use the various facilities.
My urn handles up to 6k grain bill with good efficiency, higher than that I'd be tempted to sparge on the side and do a longer boil. I have brewed some big beers using adjuncts such as maize and rice plus sugaz but about 6% is the best I have got up to with good efficiency.
 
With a small batch - you should be fine to not alter your method at all, especially with a belgian quad which is almost certain to get a chunk ofits gravity from an addition of simple sugars or candy sugar.

As has been said, the primary issue with doing "big" beers is fitting everything in your pot - if what you want is to keep the method as easy and uncomplicated as it can be, then you'll bump into limitations in the 40L pot, which is why generally 40L is the smallest size pot you hear anyone much recommending.

There are plenty of ways around it and a few have been mentioned in this thread already - the simplest is the one you yourself suggested, which is just to make a smaller batch.

I hate to be boring and conservative... But while i have no doubt you can do it, i would personally wait a while before i went with the Quad. Make a few more simple beers along the lines of the Dr smurtos, some pale ales or porters etc. Get to know your system and how it works when you aren't pushing its limits - then when you are confident driving it, put the pedal to the metal and go for the big belgian.

Like a sensible old fella telling a P plater that burnouts really are a bad idea i know... But if you can contain the excitement for a brew or two i think you'll end up with better beer faster.

Welcome to AG brewing

TB
 
Efficiency goes down when gravity goes up for any system. Sparging can have advantages. It can also have disadvantages if you end up with extra wort and have to boil longer to concentrate the sugars.

If I were going to BIAB a big beer I would work out the recipe with extra grain and use 2 pots and brew 2 batches.

Also I use a 50 liter keg and have never had trouble with the earlier example given of not being able to fit it all in. I wonder if 50 liter kegs are actually bigger then a 50 liter kettle?
 
My next planned brew is a HI-G Duvel clone. I am a BIABer and only have the good ol Big W 20L stock pot, so thinks are going to be tight. I have managed big brews with small batches in this pot before, though my efficiency has occassionally been low due to the low liquor:grist ratio. This next batch will be a split batch, and being a Belgian has the advantages of using plenty of adjuncts to achieve the high OG. For a 23L batch I will be using the following recipe:

5kg Pilsner malt
.5kg Aromatic Malt
.5kg CaraBelge
1kg Belgian Candy Sugar-clear
1kg Cane Sugar

50g Styrian Goldings @ 60
30g S-G @ 15
20g S-G dryhop

WLP540 Abbey IV yeast

I am a little worried that I am relying too heavily on the adjuncts for my hi OG, and that the resulting beer will be thin and dry, and possibly a little too hot in the alcohol taste- any suggestions or thoughts from the crowd?
 
That is a lot of sugar, I make it to be about 36% of your total extract. I think you have every right to be a bit concerned. All in you are looking at about 1.080-1 (75% efficiency)
You could try; reducing the batch size and the sugar as a percentage; mashing hotter to increase the dextrin from the grain; not putting all the sugar in at the start but feeding it in - in stages during the ferment.
The grain alone should give you about 1.053, add the Candy Syrup to the kettle would put you about 1.065, then feed with the sugar when the gravity drops to around 1.040 (the sugar will add ~0.016) good rule of thumb for sugar additions is to never take the gravity over the OG.
Personally I would make a smaller batch and use less sugar say 15-20% as a maximum.
MHB
 

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