BIAB larger batch = lower efficiency

[mtb]

Mate, please report ... I used to tie my bag off as well, until Ross said "Why TF are you doing that?".

Well tonight's Two Hearted IPA clone double batch has shown promising pre-boil readings. Dialled the recipe in for 70% BH efficiency (I arrogantly assumed I'd get a good eff, thankfully I was right) and I have overshot my pre-boil gravity target by two points. Mash eff was 85%. Proof is in the pudding though, so I will wait and see what the BH efficiency is before being too sure of my solution

 

[mtb]

Recipe FYI

 

[contrarian]

Mash efficiency is the important metric in this situation. Sounds like you e solved your problem.

 

[mtb]

Mash efficiency is the important metric in this situation. Sounds like you e solved your problem.

I think so too. Bloody love this forum.

 

[nosco]

I think alot of the bad BIAB techniques come from American sites and brewers who came from 3v and cant quite wrap their heads around it. Ive read a few American guides that say to put the grain in the bag and then dunk that into the pot. I think one guy on Brewing TV actually does that and has it tied up like hes making soup. I never really liked BeerSmith for that reason. I think its improved for BIAB lately (I have it but haven't tried it in a long time) but It seamed to me that MR Smith couldnt understand the concept of BIAB and no chill and the software reflected that. Then again I am pretty lazy when it comes to figures.

The benefit of biab is the full volume so I get pretty good extraction. I use Biabicus which doesnt use brew house efficiency so ive never understood that term. The only time sparging would help is with high gravity beers. Ive found that once the water reaches saturation point of sugars its not going to get much more without fresh water.

 

[Lyrebird_Cycles]

Ive found that once the water reaches saturation point of sugars its not going to get much more without fresh water.

I'm not sure what that means.

It sounds like you are referring to the solubility limit for wort solids but that can't be because that's about 80 Brix.

 

[nosco]

Your getting all scientific with me LC. I only speak lower middle Bogan. In thick head speak Im saying that the advantage of BIAB is that full volume mash allows for pretty good effiencies with lower and mid gravities. Its a disadvantage with higher gravities as wort, as apposed to water will not extract as much from the grain.

Im sure you can debunk the **** out of that but thats the way I heard it explained (in other words) and in my experience with high gravity bears thats been the case. ie I hit the predicted gravity pretty well with mid range but I always fall short with high gravity.

 

[nosco]

I'm not sure what that means.

It sounds like you are referring to the solubility limit for wort solids but that can't be because that's about 80 Brix.

Ok im not that thick after all. So 80 brix is 1.4250 SG? Thats pretty dam high but the "theory" is that its harder to get higher SG from biab than 3v. Im not even talking really high gravity either. Im pushing to get 1.080.

 

[contrarian]

I have also used the biabacus and it does attempt to account for the loss of efficiency associated with high gravity beers.

It is possible but is more work to get the most out of the grain. I tend to use large grain bills, a good mash out and longer boils which allows for more water in the mash and have managed a few brews over 1.100.

Other Brewers split the grain bill in half and do 2 mashes, one I to water and the second into that wort but obviously this extends your brew day by an hour or two.

I don't brew high gravity that often so don't mind the extra process when I do but it certainly is possible.

 

[nosco]

What brewing software are you using atm Contrarian? I need to try something else and stop being lazy

 

[contrarian]

I still use the biabacus for recipe formulation although I must admit to often being lazy and using nothing when brewing standard recipes. I know what grain weights and volumes I need for my system and sometimes use Brewers friend to check hop additions and IBUs but sometimes not.

Often the opportunity to brew is spontaneous and so are my recipes based on what I have on hand.

For example on Friday was going to brew a hefe but found I only had 1.2kg of wheat so made a pale ale instead that was about 60% ale, 25% Munich, 12% wheat and 3% acidulated. Around 8.5kg total will give me between 1.045-1.050 for 40L into the fermenter.

It's not very precise but I still make beer that I enjoy and I'm not that worried about being able to replicate beers, I'm happy with some variation!

That said if I am trying a new style I normally use a recipe from brewing classic styles as a starting point and punch it into my profile in the biabacus and then work from there.

 

[time01]

Great read lads, I have a 70l pot and have been just doing 20l batches but am about to do a double batch in the coming weeks and was wondering if my efficiency would be affected