Low OG ( again I know)

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Beamer

Well-Known Member
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Location
South Coast NSW
Hey guys,

Im very new to AG BIAB (6 Brews) and my last two brews have been between 6-10 points below OG. It is quite frustrating. I have been following recipes from the AHB website, using brewmate, and buying cracked grain.

The ABV doesn't bother me, what does is that I cant nail the recipe.


So from the research I have done, do I buy I grainmill crack it myself this seems to be the re occurring problem. (plus I would love to spend more time brewing so any excuse will do)

My last grain bill was:


4 kg Jw traditional ale
1.1 munich1
.300 wheat
.300 carafoam

og was 1056

I got 1046


any help would be amazing

Cheers,
Beamer
 
Have you asked your homebrew shop to mill it a bit finer? I had a similar problem and I've solved it by either getting finer crush on my grain (although others that biab use a coarser crush and get and improved efficiency) and also mashing for longer.
 
Gday Stuart, I brewed the last two days haven't had the chance to ask the brew shop, I do get all my brew supplies mailed to me. What I have read is that brewers that crack their own are getting better off by 10%. I believe this will bring my og up.

I brewed a pilsner (90 min boil) and a ale (60 min bolil) and both were shy on the og


Sorry both mashed for 60 minutes


Cheers,
Beamer
 
What does your efficiency work out to be?

I mean one option is just to order an extra half kilo of grain.
 
A bit hard to tell without more info. What was your pre-boil SG and volume compared to your post-boil SG and volume.
Could be the crush, the grain, volume of water, boil rate etc.
If you can determine whether your loss/losses are from the mash or the boil you'll go a long way to fixing your issue and dialling in your system at the same time.
 
Camo6 said:
A bit hard to tell without more info. What was your pre-boil SG and volume compared to your post-boil SG and volume.
Could be the crush, the grain, volume of water, boil rate etc.
If you can determine whether your loss/losses are from the mash or the boil you'll go a long way to fixing your issue and dialling in your system at the same time.
Gday Camo,

I'm still very new to the all grain set up still learning every time.

Starting water 32L

Mash at 66

Mash out 78

Pre boil 28.8L

og 1036

post boil 24.9L

og 1046

Any help will be greatly appreciated.

Cheers
 
Are you using any brewing software?

Looking at that I'd say the issue is before your boil so need to look at things like crush, type of grain, stirring the mash etc. Try making one change at a time so you can fault find.
My first start would be another brand of ale malt. I got terrible efficiency with JW.
Also be sure to drain the bag well.
 
Mate I brew with a 3v/biab/ and recirc 1 or 2v setups depending on the day. Efficiency varies a lot between systems. If your just starting out I'd suggest punching 64% into brew mate and adjusting your recipe to suit desired abv etc.
Then you can work on your system and increasing efficiency.
 
Water pH is worth a look too.
Got some good advice from this forum a while back and using water additions and acidulated malt has greatly improved my efficiency.

Was originally aiming to reduce tannins but efficiency improvements a very welcome side effect.
 
I'm new to AG/BIAB too, but hopefully this might help. You can calculate your actual efficiency at http://www.brewersfriend.com/brewhouse-efficiency/ ... With your figures above it comes in at about 64%. When you're formulating your recipes use 64% or 65% instead of 70% which will essentially mean ordering a little more grain. As you improve your processes you should hopefully improve your efficiency, allowing you to punch in a higher number and save a few bucks. Most likely this involves spending a few bucks too, eg on your own mill.
 
6 brews in and only 6-10 points under. You're doing fine. Keep asking questions and you will improve in no time. The above suggestions are all good especially from Pokey and Wall. Give those a try first (as well as giving the mash a stir every 15 minutes) and see if that improves your efficiency. If it does somewhat, then research some more and you will find techniques that suite your method thereby improving your beers.
 
GDay Lads,

i brewed Dr Smurtos Golden Ale today, I did improve my effiency today I did do a 90 min mash with a stir every 20 mins, I did give a better stir through mash out time,and squeezed the bag till dry. I have recalculated all my volumes in the urn aswell. Made better records of my boil off.
Also learnt I was whirlpooling too early which was contributed to my trub loss.

After all that I was still 6 points under the predicted OG. But this was at Pre boil and post boil.

So it may be a rookie mistake but I believe it could be the grain, so I'm going to buy a grainmill and from now on use a different base grain.

Thanks all for your help and anymore advice would be great.

Cheers,
Beamer
 
So it may be a rookie mistake but I believe it could be the grain, so I'm going to buy a grainmill and from now on use a different base grain.
Sounds like a bit of overkill tbh. Just reduce your efficiency in your brewing software to match your system. Its not a point of failure on your part not getting the 70% efficiency some other bloke got when compiling the recipe. Everyone's system is different and will be getting different results in that respect. Save a few litres of water in a jug to do a ghetto sparge and rinse the grain in the bag. Theres a ton of sugars left in that grain bed regardless of how hard you squeeze the bag.
 
I don't BIAB. I got an appropriate esky, a hardy 75lt (with threaded tap outlet) for $95 on special. I batch sparge. You need to consider a bigger pre boil volume.
$0.02
BIAB is a recipe for mess and trouble and swaring in frustration. In my little experience. I cant see why its so popular.
Mash in esky and set up a (bazooka? screen tube filter thingamy) fit in the outlet hole as a filter. Learn the Vorlauf method. It feels much better when you have to tweak your software efficiency UP! not down. I set my Beersmith at 81% to match what I got on the last brew. :beerbang:
 
Danscraftbeer said:
BIAB is a recipe for mess and trouble and swaring in frustration. In my little experience. I cant see why its so popular.
I can't say I agree with that. I've been doing it for 3 and a half years now and have had barely any issues with it at all. I'm sure it's popular because there are many others in my situation. I constantly hit about 75-76% efficiency on my system, sometimes a little higher. I'm happy with that, it's consistent, and that's what makes recipe design easy, not what that number actually is.

Obviously, you don't want it ridiculously low, though.
 
Good points. I just skipped the BIAB all together and went straight to the esky mash tun method. I've only BIAB for under 12lt brews and made a hole friggen lot of sticky mess for little yield.
Its just not for me.
Yet I can pull off a 40lt brew with batch sparge esky mash no mess, no probs. I admit maybe I have a bit more space and a 20 pale bucket (for wort drainage) and a 50lt tub as a drip tray etc.
A Keggle for boiling up to 55lt pre boil.
 
Get your local water report and see what the PH is and adjust accordingly . I biab with an urn and my brew house efficiency is set at 80 %. I own a 30 ltr urn, so a sparge/mashout step is required to meet volumes . You can achieve good efficiency with biab , even full volume, if that's what you do. Anyone who claims otherwise is talking out of their arse.
 
Thanks again to all for the advice. I have done alot of reading over the last couple of days i.e the importance of water and mash ph, something i should have done before I started BIAB.

I found a water report from my local area and ph levels where between 8.2 and 9.6.

I will be purchasing some ph testing strips some 5.2 stabilizer before next brew day.

Hopefully this will provide some more insight for myself again.

Cheers,
Beamer
 

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