Falling short of target OG

[Beamer]

I think you have too much pre boil volume for a one hour boil mate, I had a similar problem when I started biab. If your grains soak up 5 litres that gives you around 33 litre pre boil and thats something I would use for a 90 min boil in a crown urn. With loss of 4.7 to trub for a 23 litre batch.
I use brew mate so I cant comment on beer smith.

 

[dannymars]

The strike volume goes up to accommodate the extra grain adsorption.

How do you crush grain? maybe try a finer crush? you could also reduce your strike volume and try a mini-sparge with some hot water from the stove poured over the grain bag once you remove it from the kettle.

 

[DigitalGiraffe]

Definitely too much strike volume. I average around 32-34litres for my brews in a keggle.

Try using the scale option in beersmith, it will adjust your quantities for you. If you change batch size and efficiency on the recipe screen it won't adjust anything for you.

A quick follow up on my issues... It looks like my issue was a result of a cheap electric thermometer. I've done two brews since buying a liquid thermometer and have exceeded my OG both times. I'm bumping my efficiency up to 70-75 from the 60-65 that it was on. Yesterdays brew I was aiming for pre-boil gravity of 1038, I hit 1048! Post boil my target gravity was 1052 and I hit 1060 Happy times!

 

[Rocker1986]

Your process sounds fine although I'd agree with the others that if you are aiming for 22L then the strike water is too high. My strike water is usually about 10/11 litres more than the intended batch size. You could try mashing for 90 minutes instead of 60. I don't think a finer grain crush would make improvements although you might as well try it and see, but a coarser crush may well do. In my case a finer crush made things worse, but a coarser crush improved my efficiency. Doesn't sound like there's any problem with your hydrometer accuracy, so that's not the issue.

I think the issue lies with my BeerSmith Settings I just dont know where or how it should be set up. I have bene following the wizard to set it up and thought I had it bang on but clearly not!
Thanks again!

I think your Beersmith settings are off, but they wouldn't be causing shitty extraction during the mash. If the extraction was better, you'd still end up under the OG due to the increased volume, but it would only be a few points, not 20. The wizard is great for setting up equipment profiles, but you need to use real world numbers that you measure in your own brewery. Measure how much volume you have pre-boil, your boil off in litres per hour, measure how much trubby shit you get in the bottom of the kettle etc. Beersmith won't change the batch volume to increase the OG, it will increase the grain bill. You have to change the batch size manually. Take a gravity reading pre boil as well as post boil.

I think low 50s efficiency is way too low even for BIAB; it's not expecting too much to get it up to the mid 70s, and it can be done quite easily. I'd be pretty annoyed if I was using 5kg of grain to end up with a bloody light beer. :blink:

 

[Ollieb]

Your process sounds fine although I'd agree with the others that if you are aiming for 22L then the strike water is too high. My strike water is usually about 10/11 litres more than the intended batch size. You could try mashing for 90 minutes instead of 60. I don't think a finer grain crush would make improvements although you might as well try it and see, but a coarser crush may well do. In my case a finer crush made things worse, but a coarser crush improved my efficiency. Doesn't sound like there's any problem with your hydrometer accuracy, so that's not the issue.


I think your Beersmith settings are off, but they wouldn't be causing shitty extraction during the mash. If the extraction was better, you'd still end up under the OG due to the increased volume, but it would only be a few points, not 20. The wizard is great for setting up equipment profiles, but you need to use real world numbers that you measure in your own brewery. Measure how much volume you have pre-boil, your boil off in litres per hour, measure how much trubby shit you get in the bottom of the kettle etc. Beersmith won't change the batch volume to increase the OG, it will increase the grain bill. You have to change the batch size manually. Take a gravity reading pre boil as well as post boil.

I think low 50s efficiency is way too low even for BIAB; it's not expecting too much to get it up to the mid 70s, and it can be done quite easily. I'd be pretty annoyed if I was using 5kg of grain to end up with a bloody light beer. :blink:

Hey Rocker...

So as a rule of thumb do you always just go for 10/11L greater than your intended batch size and ignore BeerSmith? Or are you saying this with qualification because that is what BeerSmith spits out and tells you to do? I assume the latter as you have probably configured it correctly unlike me!

Also when you suggest obtaining "real world number" would you do this during a brew? I assume you need to actually do a brew because you need to calculate the grain absorption pre boil post mash right?

Given you reckon low 50's is too low for efficiency what would you suggest I set mine too until I start hitting the targets? 60%?

Along with everyone else I really appreciate your input and the time taken to respond. This is slowly starting to make a little more sense.

Thanks very much!

 

[Rocker1986]

I do ignore Beersmith for the strike volume but that's because I worked it out myself over a number of batches when I first started. Mind you, Beersmith's calculation is not very far off what I do use, because the equipment profile is set up using real measurements that I've taken from my brew days.

Yes, you will need to measure things during a brew day, or across a few brew days to get an average. You already know your strike volume, but you'll need to measure the pre-boil volume to determine how much is lost to grain absorption, although it appears this figure is default in Beersmith and if it can be changed I haven't worked out how to yet. For some reason I lose very little to grain absorption. Measure your pre-boil SG too, this along with the pre-boil volume is used to calculate mash efficiency - if this is low then your overall efficiency will also be low. Measure how much is boiled off over an hour. I get a 3 litre boil off per hour.

As for your efficiency, you should set it to what you're actually getting. Obviously this is worked out by the volume in the fermenter and its SG, which is OG of course. If it starts to show consistent improvement then you can increase it in line with that. There's not much point setting it to a number higher than you're getting because you'll always end up falling short of what you're aiming for.

 

[MHB]

Ok Ollieb, Just quick and dirty
You have put in 5kg of base malt, the "Coarse Grind As Is" (CGAI) potential is going to pretty dam close to 75-6%, so the amount of extract available is close to (5*0.75)=3.75kg
When you pull the malt out around 0.8-0.9L/Kg of water/kg of malt will come out with the expended grain so roughly (5*0.85)=4.25L (or kg same, sameish)
So at the end of mashing you should have (38.8L-4.25L)=34.55L left in the kettle (give or take)

Mass Extract = Volume *SG*oP, (34.55*1.030*0.075) = 2.67kg of extract

At 100% mash efficiency you could have obtained 3.75kg, you got 2.67kg, so your efficiency is (2.67/3.75)*100=71%
Call it 70% maybe not exact, but within a couple of percent.
Mark

 

[MHB]

I'm going to suggest that 70% is on the low side, 80% isn't hard and I know a lot of home brewers getting over 90% mash efficiency.
You need to take a long hard look at your basic parameters. Temperature being the most influential variable, mash mixing (no dough balls), actual masses of grist and water... leave water chemistry alone unless you have extremely hard water, some way to check your pH would be a help.

Had you in fact got the 1.050 you were anticipating, from the same equation as above, (34.55*1.050*0.125)=4.11kg of extract
Roughly 110% efficiency, so there is something seriously wrong with your settings.
Mark

 

[Rocker1986]

I think he's talking about 1.050 as the post boil SG of the 22 litres intended for the fermenter rather than the pre-boil SG. 5kg of grain would get me to that figure or thereabouts on my setup. I normally get mid-high 80s mash efficiency and about 10% less than that for the overall efficiency.

 

[pcqypcqy]

My experience with beersmith is that you need to be very careful. There seem to be many places to enter the same parameter, and you may not realise you've done this as you go through, and end up changing something somewhere else that effects what you were trying to put in. Double and triple check everything.

Beersmith also has a lot of features that will only apply to commercial settings, measurements and so forth. You need to read through the help files and online to really understand what each one means. I'd steer clear for brewing forums for help with these definitions as each home brewer will assume different things when you talk about different efficiencies, volumes, etc. Check the beersmith documentation.

That said, I only use it as a guide. When I initially started all grain I had a bad manifold in and esky and was only getting 50 to 60%. With a better manifold, stirring and a long/slow fly sparge, I've gotten that up to around the 72% which beersmith will just assume for you. I've found calculating the actual efficiency in beersmith is a bit tedious, there are some spreadsheets floating online that you can google that might be easier to use.

Like the others said, assume a value, brew it, if you were under then run the calculation and adjust accordingly for your next brew. Once you're consistent, then you know you've got a number you can trust and start working from there.

 

[Ollieb]

Wow guys... all such good advice and I really appreciate the input everyone has contributed!

I think the next thing for me to do is to have another brew day and try and start obtaining my numbers for accurate calculations.

I think I'm going to try to re-brew my last beer and just try 10L more volume in my pre-boil volume than intended for the fermenter and just see what numbers I get. I'll start with 34L and go rom there as I try to throw in my fermenter 24L.
I also think I'm going to give BeerSmith a wide birth for now and might try using an online calculator and or the spread sheet I have seen on here.

Falling short of a miracle I do not see a short fix here. It will be a long road of trial and error!

Also just as a side note:
The SG I am testing and trying to hit is the SG post boil and what I am tipping into my fermenter. So Rocker1986 is correct there.
I definitely did not have any dough balls as I was stirring it occasionally during the mash.

Thanks again to everyone for helping out and commenting! Legends.

 

[pcqypcqy]

No worries. Just so you don't take me the wrong way, Beersmith is an incredible tool with lots of powerful stuff in there. However, like all tools you need to know how to use it properly. It's user interface could really do with an overhaul.

I'd suggest you do as you propose, but keep plugging numbers into Beersmith and see what it tells you. Don't take it as gospel, but it'll help you understand what's what.