Typical Efficiency Of Biab Method

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redalert

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Hello mates,

I am from the States and love the idea of BIAB but would like to know the typical mash effieciency I can expect by doing a 19L batch. I will be mashing about 4kg of grain in 38L of water. Then I will remove my grian bag, hopefully leaving me with 20-24L of pre-boiled wort. Thanks for your help.
 
You expect to lose 14-18L of water to 4kg of grain???

A normal rate is more like 0.5L/kg of grain...

I have been hitting 65-75% thus far, but I think a mahout may help me.
 
Hello mates,

I am from the States and love the idea of BIAB but would like to know the typical mash effieciency I can expect by doing a 19L batch. I will be mashing about 4kg of grain in 38L of water. Then I will remove my grian bag, hopefully leaving me with 20-24L of pre-boiled wort. Thanks for your help.


try about 31 litres
 
You expect to lose 14-18L of water to 4kg of grain???

A normal rate is more like 0.5L/kg of grain...

I have been hitting 65-75% thus far, but I think a mahout may help me.


+1 on the water loss to grain. I expected to lose more, but once I put the spent grain in a bucket and retreived some more wort from it, I found I had too much wort - but still hit OG that I had based on 75% as I had underestimated the efficiency. Got almost 80%.
 
My goal is to have 22-24L pre-boil after taking my grain bag out and letting it drip off for at least 30 minutes without squeezing.
 
Okay, I have just pulled the stats on one of my latest batches.

Strike water =33L
Preboil =30.23 (give or take, this was with 5kg of grain)
Loss to evap = 3L
Loss to trub =3L
Cooling loss = 1.21L

Grand scheme of it all, 33L intial strike =23L to fermenter for me with my equipment.
 
Im getting 76% with 6kg of grain. In my next batch im using 8.5kg. Should i factor in a drop in effieciency? If yes how much?

Anyone got any tips for setting up My Equipment in Beersmith, reguarding Biab and nochill?
 
If you drain without squeezing,you can expect to lose about 0.75L of liquid to grain absorption - and thus about 3-4% of your efficiency. With a goodly squeeze, it will be closer to 0.5L/kg

If you are looking for a pre-boil amount of 22-24L (lets say 23 shall we?) and you plan you use 4kg of grain - then you want to start with

23 + 0.75 x 4 = 26L without squeezing - and 23 + 0.5 x 4 = 25L

Efficiency - Assuming you get everything right and you have had a few brews worth of practice - you will most likely end up with a stock efficiency (measured at pre-boil) of 75% give or take a few points. Less by 3 or 4 % if you don't squeeze

Work on 70% for a few brews and see how you go. Tweak your expectations according to the results you get. If you are getting less than 70% mash efficiency (pre-boil) on normal strength beers... then you are most likely doing something a little wrong and could improve your methods. Anything above that - you are fundamentally good and the rest is about experience and refinement.

If you are looking for 23L pre-boil (60min boil) then :-

With 26L strike water (assuming you really don't want to squeeze) and 4kg of grain (US 2 row pale) - I would expect you to have a pre-boil volume of 23L @ a gravity of around 1.037 (+/- 0.002) - giving you around 19.5L of post boil wort at 1.043 (+/-)

I think your batch size is a little small - I estimate you will only end up with around 16-17L of finished beer - but that may be what you are looking for.

An extra 0.5kg of grain and factoring for a 28L pre-boil would give you 18-19L of finished beer at roughly the same strength
 
Im getting 76% with 6kg of grain. In my next batch im using 8.5kg. Should i factor in a drop in effieciency? If yes how much?

Anyone got any tips for setting up My Equipment in Beersmith, reguarding Biab and nochill?

Yes you should - how much??

you will be losing to grain absorbption (assuming you squeeze) 2.5 x 0.5 L of wort extra - so 1.25L lost that you didn't lose before. Thats extract and therefore efficiency onto the compost heap. Assuming you are aiming for your normal pre-boil volume then the extra loss is roughly the 1.25L expressed as apercentage of your normal pre-boil.

so for instance if you normally have a pre-boil of 30L - then your 1.25L is 4.2% of that.

So I would factor in a minimum of 4% less efficiency and maybe a couple for luck

With 8.5kg of grain - I guess you will be lucky to top 70%
 
I've got horrendous water chemistry here, fairly alkaline, and work with a 60% efficiency figure. I start with ~35L and finish with around 22L after a few litres being lost to trub and perhaps 10 or 12L to evaporation during the boil (often >90min boil). I'm cool with this, things are simple for now until I work everything out to a tee.

I'd go with the advice to have a slightly larger preboil volume, otherwise you'll probably end up with a very small batch.

Cheers - boingk
 
Hello mates,

I am from the States and love the idea of BIAB but would like to know the typical mash effieciency I can expect by doing a 19L batch. I will be mashing about 4kg of grain in 38L of water. Then I will remove my grian bag, hopefully leaving me with 20-24L of pre-boiled wort. Thanks for your help.

As others have mentioned already, your figures don't really add up. Perhaps something got muddled in the conversion to metric?

But to answer your question, I typically get high 70's to low 80's for efficiency into the kettle. I also crush quite fine since I don't have to worry about stuck sparges.

Good luck and let us know how you go.
 
What part of the Americas do you come from, the North or the south?.This could explain your difference.I find some people in Queensland report to have over 100% efficiency yet here in WA we only get about 80%. ;)
GB
 
I find some people in Queensland report to have over 100% efficiency yet here in WA we only get about 80%. ;)
GB

[Edit: I will address the BeerSmith question posed earlier in this thread but first...]

LOL Nev!

But, what Gryphon is saying has a lot of truth. A lack of quality measuring equipment that exists in home brewing amongst other things leads to some bewildering claims on efficiency and a totally inappropriate focus.

I now, after, well over 50 BIAB brews plus many traditionals and a hell of a lot of equipment, can say that you can confidently expect 75% efficiency with BIAB if you follow the procedure at the end of this post. This is the same 75% you should expect from batch-sparging.

...

But, did I say what efficiency figure I was referring to?

No! So the 75% I quoted above is of absolutely no use to you as is any other efficiency figure you hear quoted by BIABers or traditional brewers.

Please stop and think about this.

...
...
...

Was the 75% I quoted above or the efficiency figure that anyone quotes here referring to mash efficiency, efficiency into kettle, post-boil efficiency, efficiency into fermenter or efficiency into packaging?

What efficiency figure were they quoting?

...

Some people in their efficiency claims are quoting their volume and sugar into the kettle. Others are quoting their volume and sugar into the fermenter (after all the break and trub are gone) and anything in between.

A 90% pre-boil efficiency does not mean a 90% efficiency into your fermenter after all break and trub is removed yet many brewers choose to quote the former as their efficiency.

A 55% efficiency into fermenter figure after break and trub is a perfectly respectable figure and one rarely quoted.

I have written essays on this efficiency myth many times before (just browse through my last ten posts - I must have gone on about it there at least once!)

....

Why is 75% Quoted So Often?

You will see a 75% "brewhouse" efficiency figure posted in a lot of recipes on any brewsite. This figure comes from most common brewing software and the terminolgy and programming they use for this figure has confused a billion brewers before you or I. It is a ******** figure and has nothing to do with a regular brewhouse efficency. BeerSmith and ProMash's Brewhouse Efficiency is really post-boil efficiency. (And there can be a lot of variance there!!!)

This though basically means it includes all your trub and cold break.

But, you may ask, why do they ask me for my trub and cold break figures in BeerSmith?

A great question, because none of us know! Try changing them. It will make no difference to your brewhouse efficiency figure reported in the program!!! (If you think this isn't right, do a search on this forum on BeerSmith. Read the 300 posts in each thread and you will see the same conclusion every time.)

As a new brewer, with half a brain in their head, you will keep thinking that this can't be right. Surely, a brewing program would describe brewhouse efficiency accurateley???

Well, the only answer for that is that I am writing this in Western Australia where no one wants daylight saving because we are on the far edge of a time zone. The government here really wants it and are telling us it is because of business reasons, i.e. so we can communicate better with the rest of Australia. So, we have had a 3 yr compulsory trial here but guess when we turn our clocks back? A week before the eastern states.

%^&* FFS! It makes no sense at all!

When you can explain the logic of that then I might have a hope of why computer programs call their post-boil efficiency, brewhouse efficiency.

It is incorrect and confusing.

What Should We Do

Stop quoting and worrying about your own efficiency figures. (Unless you are really confident in your measuring equipment, technique and understanding of how to properly quote efficiency.)

Stop focussing on efficiency figures you hear about from others. (Well for the same reasons above!)

Stop focussing on posts that say I just got two (or ten) more percent efficiency on my last batch by doing this... I'm sure I made these sort of claims when I first started out brewing. Now I realise that such claims are well-meant but now know that, for a myriad of reasons, you can't make a claim unless you have repeated it at least five times in a controlled environment. Try doing that in a home brew environment! (What proved this to me is having two side by side rigs. This is as good as it gets for the home brewer.)

Start focussing on recipes you like. Meet and taste other AHBrs beers. If you find a recipe you like, it will taste great even if you brew it at plus or minus ten percent of their quoted ABV.

Start focussing on things relevant to you. Are you wanting to brew a champion beer or an easy drinking light-tasting ale that tastes like a lager that you and your friends will like? The latter is a good challenge for a beginner anyway but.. Are you brewing for your own enjoyment (and your friends) or to gain accolades for some obscure beer style at a comp? Are you focussed on making brewing easier? For any of the above goals, efficiency is pretty much irrelevant!!!!

Start focussing on the way that is easy for you to measure. If you use a brewing program then end of boil will be the easiest guide for you but even that has problems. Probably less than the other ways I have tried which all have their down falls.

How To Measure Your Efficiency

When following a recipe, original gravity is the thing to strive for. OG measurements don't vary much post-boil or into the fermenter so this is the easy factor to measure.
.....

As usual, didn't expect to write all the above. I was about to write an easy way of measuring volume but suddenly realised that, whilst the answer is simple, the measurement of volume has countless qualifications and corrections which would require another essay. e.g. Are you chilling or no-chilling? Are you using a counter-flow or immersion chiller?

See what I mean?

Anyway, I hope the above will get one or two people just focussing on recipes.

Spot ya,
Pat
 
My above post promised achieving 75% efficiency if you followed a certain procedure that I would write at the end of the above post. Sorry, I got side-tracked :rolleyes:

Will whack the procedure in the main BIAB thread in the next few days though it is nothing new.

Spot,
Pat
 
Im getting 76% with 6kg of grain. In my next batch im using 8.5kg. Should i factor in a drop in effieciency? If yes how much?

Anyone got any tips for setting up My Equipment in Beersmith, reguarding Biab and nochill?

Figure your water requirements by hand.

I gave up on beersmith because it had no way to adjust grain absorption. I have no idea if they fixed it in some other release as I gave up about a year ago. I also gave up because of the odd calculations like PistolPatch references.
 
I average about 4.5-4.7kg grain per batch. Water, I use is 29L into the pot @ 69c, and use 3L @ 80-85c for a batch sparge. (I drain the bag, then drop it into the bucket and add the water stirring, then redrain) I drain my bag mostly of what I can get out of it, and it all gets added back to the kettle. I average 75-80% pre-boil efficiency. I'm not 100% worried about gaining a real high efficiency; I can add an extra 200g of grain up front if I needed to balance a lower efficiency. I am more concerned about getting a consistent efficiency so I can calculate my grain bill correctly.

QldKev
 
Wow now I am totally confused. But the basic formula is:

- squeezing the bag:
.50L lost/Kg of grain
-not squeezing
.75L lost/Kg of grain

That's all I wanted to know. Somehow I thought the grain would absorb more water. Thanks.
 
Last few brews I have started with 36L with 6kg of grain and ended up with 32L preboil but I dont squeeze really hard like some might.
 
Last few brews I have started with 36L with 6kg of grain and ended up with 32L preboil but I dont squeeze really hard like some might.



That's the hardest thing about brewing for me, it's getting the desired numbers consistently.
 
As mentioned on another thread, using 4k of Galaxy and 1k of adjunct.. rice or maize ... to my surprise I have ended up with an extremely free draining bag which after a wee bit of squeezing was almost dry and felt very light taking it out to the compost afterwards. Probably cellulose, lignins or proteins or something remaining in the spent grist in the form of Hull type stuff? Seems to be a good little booster method for BIAB, I wouldn't do it for heavier styles like old ales, best bitters, ambers etc but for lighter bodied brews it's a style of mashing I'm going to explore a bit more rigorously.
 
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