Falling short of target OG

[Jens-Kristian]

I'd be very surprised if someone was getting 25 litre batches out of a mash in of 33.6 litres with a 5L per hour boil off

I entirely agree, but I'm open to whatever may be happening.

 

[DigitalGiraffe]

DigitalGiraffe,

Sorry, I don't want to come across as the 'did you check' guy, but I can't help noting that with 4.8kg of grain and at 72% efficiency, 1044OG is what you'd get out of a 25 litre batch. How large is the batch you're brewing?

You say you mashed the 4.8kg in 33.67l of water. With the boil-off rate of 5l per hour, give and take, that would take you down towards the 25 litre mark and then somehow sounds pretty right to me.

I don't use BeerSmith, but are you sure you've added the right volume of wort in there? Does BeerSmith have separate fields for mash volume and boil volume? I've sometimes made the mistake of putting the final 25l volume into the field in my software that's for mash volume and then not noticed to begin with that my boil volume is set to 20l. As it's the boil volume that is linked to the OG, that obviously inflates the OG beyond what my grain bill allows.

Just a thought, and I may be missing something here, but in my setup I wouldn't expect 4.8kg of grain to get me to 1053 on a 25l batch as that would require that I get 87% efficiency, and in my current setup, I've never gone anywhere north of 80% - usually more in the 70-75% range. Admittedly, my setup is ridiculously basic.

Don't be sorry, I'd be more than happy for someone to point out I was doing some stupid so it could be easily resolved.

Generally I aim for a 21L batch (Usually lose a couple of litres at the bottom with trub) which gives me 19L to bottle. I also lose about 3-4L in the bottom of the keggle.

Beersmith autocalculates the boil volume and it's listing 29.96L if I have 5LPH boil off, Lose 3L too keggle, 2L loss in Fermenter and want a batch of 21L.

So perhaps my grain bill isn't large enough? Whats the average absorption rate?

 

[DigitalGiraffe]

I've just had confirmation that my water pH is generally 7.2 but can vary between 6.9-7.2.

I also re-entered the recipe for my last brew into beersmith with Tot Efficiency now set to 65%. I did also notice that the recipe was for 20L and my default was 21L so that extra water may explain why I missed my target on this brew but not my others. The total volume of water required has dropped from 33.65 down to 31.85 for my 4.8kg grain bill.

I'll check the batch sizes against the original recipes tonight.

 

[Rocker1986]

One litre extra won't throw your OG out by 11 points or whatever it was. The total water sounds about right, with my urn for 21 litre batches I use about 32 litres at the beginning. You don't have to have Beersmith automatically calculate the boil volume either. I edited it to suit my own system once I got a few batches done and worked out what it actually was. I brew two different batch sizes as well, 21 and 25 litres, depending on whether I want some surplus bottles or not. I have two separate profiles set up in Beersmith for these.

My last batch that I kegged was also a 21 litre size batch; it used a 3.73kg grain bill and I ended up with an OG of 1.0425; giving me 76.2% overall efficiency (I actually got 22L into the FV making the efficiency 80%, but intended size was 21L so I went with that). Basically exactly what you got from a kg less of grain. I think your volumes in Beersmith sound ok, but there's something happening in the actual brewing process somewhere that is causing issues with extracting the sugars from the grains.

I think having the grain milled too fine is detrimental in BIAB and that double milling is unnecessary, however, that is purely based on my own personal experiences. I don't have any proper research/data to confirm it - that's just what happened in my situation. As soon as I went to a coarse crush with very little grain flour, my efficiency improved. There were other things I did, such as stirring the mash a bit every so often, and discovering that my hydrometer was reading 2 points low as well. I've experimented on the last 2 or 3 batches with not stirring the mash at all except at dough in and during temperature ramp ups, and it hasn't really made any difference. So maybe the stirring isn't really necessary.

I haven't done much at all in regard to mash pH, mainly because I have no problems with the brewing process or how the beers turn out in the glass, so I figure it must be sitting pretty much where it should be. Would be interesting to find out what it really is though, might have to look into a decent pH meter at some point.

 

[TheWiggman]

You're missing one critical measure here - volume. Starting volume is fairly relevent, but when you're calculating brewhouse efficiency you're talking about how much ends up in the fermenter at a given gravity. That is to say that by increasing the amount of liquid you extract from the kettle you'll immediately increase the efficiency.
What was your volume in the fermenter? How much were you leaving behind in the kettle? What was your pre-boil gravity?

 

[MHB]

Apology time

Just doing a quick rough as calculation I thing you could be getting close to 1.050-1.052 with what is in the post, just making standard assumptions about the grist and type of beer.
For the water to be so bad that it is what is knocking the best part of 20% out of your efficiency is improbable (nearly impossible for anything that comes out of a tap in Australia.
Get a decent thermometer and check your temperatures, I'm quietly confidant that you will be a fair way out!.
For about the 100th time - get a decent glass laboratory thermometer you can trust, use it to calibrate everything else, don't trust anything with batteries or that runs on springs.
Mark

I didn't take out Brewery efficiency, that's about the theoretical yield, so with your grain bill, in the amount of water you mashed into - without a sparge, what you got is pretty much on the money.
So in short you aren't doing anything too wrong, you just need more malt to get a higher gravity.

I'm not apologising for suggesting you get a good glass lab thermometer, that's still a very good idea.
As mentioned above it is a good idea to do a work back from "How much beer you want" adding on all the losses, Left in the fermenter (maybe 1L), Left in the kettle 5-10% (measure it), Evaporation during the boil (you said 5L/h), Absorbed by the malt (about 0.9L/kg so 4.8kg*0.9=4.32L), splashing, samples, evaporation during mashing... (about 2% of mash water).
Should give you a very good idea of how much water you need to start with.
Mark

 

[DigitalGiraffe]

Apology time
I didn't take out Brewery efficiency, that's about the theoretical yield, so with your grain bill, in the amount of water you mashed into - without a sparge, what you got is pretty much on the money.
So in short you aren't doing anything too wrong, you just need more malt to get a higher gravity.

I'm not apologising for suggesting you get a good glass lab thermometer, that's still a very good idea.
As mentioned above it is a good idea to do a work back from "How much beer you want" adding on all the losses, Left in the fermenter (maybe 1L), Left in the kettle 5-10% (measure it), Evaporation during the boil (you said 5L/h), Absorbed by the malt (about 0.9L/kg so 4.8kg*0.9=4.32L), splashing, samples, evaporation during mashing... (about 2% of mash water).
Should give you a very good idea of how much water you need to start with.
Mark

No need for apologies. I'm stoked and thankful that everyone has offered so much help. Bunch of legends!

I will be sourcing myself a decent thermometer. You can never have too much brew gear right?

 

[Ben1]

Keep at it with beer smith. It's terribly confusing and counter intuitive to set up but once you get your head around it, it makes recipe formulation a breeze.

The key with efficiency is to not 'aim' for a certain efficiency but instead measure everything, plug it into beer smith and it will tell you your efficiency. If you then use that number going forward your beers should be spot on.

There have been some great suggestions to improve your efficiency but at this stage you want consistency rather than a really high number.

Efficiency just means how much grain you require to get a certain OG. If you have a low but consistent efficiency, you can just buy a little more grain (which beer smith will tell you the amounts)

 

[DigitalGiraffe]

I'm planning a brew for this weekend and have lowered the efficiency in beersmith as suggested. Hoping to grab a decent thermometer by the weekend also.

This is the brew I'll be putting down and have scaled it to 21L using beer smith.

https://www.brewtoad.com/recipes/mountain-goat-fancy-pants-clone-1

Here are the numbers that beer smith has given me. Do they sound about right?



Recipe: Mountain Goat Fancy Pants 40L scaled - 18/7/16
Brewer: Sparrows Talon
Asst Brewer:
Style: American Amber Ale
TYPE: All Grain
Taste: (30.0)

Recipe Specifications
--------------------------
Boil Size: 29.96 l
Post Boil Volume: 24.96 l
Batch Size (fermenter): 21.00 l
Bottling Volume: 19.00 l
Estimated OG: 1.060 SG
Estimated Color: 17.5 SRM
Estimated IBU: 33.7 IBUs
Brewhouse Efficiency: 62.00 %
Est Mash Efficiency: 70.9 %
Boil Time: 60 Minutes

Ingredients:
------------
Amt Name Type # %/IBU
4.94 kg Pale Malt, Traditional Ale (Joe White) 75.2 %
0.43 kg Caramel/Crystal Malt - 60L (60.0 SRM) 6.5 %
0.39 kg Munich, Light (Joe White) (9.0 SRM) 5.9 %
0.39 kg Cara-Pils/Dextrine (2.0 SRM) 5.9 %
0.28 kg Carared (20.0 SRM) 4.3 %
0.14 kg Chocolate Malt (Joe White) (381.0 SRM) 2.2 %
10.79 g Cascade [5.50 %] - Boil 60.0 min 6.4 IBUs
10.79 g Galaxy [14.00 %] - Boil 60.0 min 16.2 IBUs
10.79 g Cascade [5.50 %] - Boil 15.0 min 3.2 IBUs
10.79 g Galaxy [14.00 %] - Boil 15.0 min 8.0 IBUs
1.0 pkg White Labs California Ale
11.00 g Cascade [5.50 %] - Dry Hop 7.0 Days 0.0 IBUs
11.00 g Galaxy [14.00 %] - Dry Hop 7.0 Days 0.0 IBUs


Mash Schedule: 001 BIAB Mash
Total Grain Weight: 6.57 kg
----------------------------
Name Description Step Temperature Step Time
Mash Step Add 33.98 l of water at 73.1 C 67.8 C 60 min

Sparge: If steeping, remove grains, and prepare to boil wort

 

[Rocker1986]

I remember reading on here recently that someone had been having issues with Joe White malts and lower efficiency than with other brands of base malt. I wonder if that might be something to do with it? :unsure: I haven't used JW for a long time so I don't know what it's like now. Back then it was fine though.

 

[DigitalGiraffe]

I remember reading on here recently that someone had been having issues with Joe White malts and lower efficiency than with other brands of base malt. I wonder if that might be something to do with it? :unsure: I haven't used JW for a long time so I don't know what it's like now. Back then it was fine though.

My lhbs sometimes has Gladfields so I'll give that a run if they have any in stock. I remember reading that somewhere also.

 

[dr K]

I would be very surprised if Joe White (or any other major malster) had a lower than optimum efficiency.

K

 

[Beamer]

I was using Joe White and had low efficiency 58-62 %. Read that JW was causing the problems. I bought a better thermometer a grain mill and did some ghetto sparging. Efficiency improved to 67-69%. Then I went to an overnight mash and double batch sparging. Efficiency has improved 75-77% and still using Joe White. Happy with this consistency and now this is the method I will continue to use.

Oh and the overnight mash saves me about 2 hours on brew day. Win win situation for me.

 

[GalBrew]

I have heard certain pro brewers first hand who hate JW due to low efficiency and consistency issues.

 

[Rocker1986]

I haven't used JW for about 3 or 4 years, it was fine back then but I don't know what it's like now. My main two base malts are Fawcett's floor malted Maris Otter, and Weyermann Bohemian Pilsner. I consistently get around the 75-78% (overall) efficiency with 'normal' mashing procedures. Sometimes it jumps up to 80%. I'm just doing BIAB no sparge, have not tried an overnight mash yet as I've seen no need to bother. Pretty happy with it!

 

[DigitalGiraffe]

LHBS was all out of Gladfields so I had no choice but to go with JW. It'll still taste fine so it's not the end of the world.

Do you think my quantities in the above recipe look like I can achieve the OG of 1060?

 

[Rocker1986]

In my system, the pale malt alone nearly hits 1.060 in a 21L size batch. :lol:

The whole grain bill gets to 1.073 OG in 21 litres. Dropping the efficiency back to a more expected 70% gets around 1.068 OG. I think you should be fine to hit the 1.060 target OG. Seems like an awful lot of cara/crystal malts in it though :unsure:

 

[DigitalGiraffe]

This will be the 3rd time I've done this recipe. I thought it had a lot of cara/crystals initially but maybe my poor efficiency has caused it to have little impact? I'm a big fan of the MG Fancy Pants and I think this recipe actually tastes better.

Thanks for giving it the once over!

 

[Rocker1986]

That's a possibility I suppose, yeah. I enjoy that beer too, haven't seen it around in the bottle shop lately though, which is annoying because I'd like to have it again.

 

[DigitalGiraffe]

They mentioned on Instagram that they'll be rolling it out in 6packs in the coming months to replace the 4pack. Win win!