Low Efficiency - How to improve

[David Woods]

I am making mostly 4.5 - 5% IPA's Blonde Ale's and Pilsners which I make from either all grain kits or AG recipes and are generally around 5 - 6kg of grains. I mash in a 30L Brew Monk with 18L water - there is about a 4.5l dead space and I sparge up to 28L. I usually end up with 24L after boil

I am very careful with temp control and mash for 1 hour+ and same for boil. I check conversion with iodene and all seems good.

However I never seem to hit the expected SG - the last brew for example should have been 1.052 but was 1.044. I also used an efficiency calculator (Brewers Friend) which was telling me my efficiency was around 65%.

I get my grains crushed from Malt Miller so assume there would be no issue there so how can I improve this and should I bother - I don't care if the ABV is a bit lower than expected but if there are some things I can do it would be good - would improved efficiency improve flavour? I was wondering if a full volume mash would improve things or not.

Any advice welcome

Thanks

 

[Sandimas]

However I never seem to hit the expected SG - the last brew for example should have been 1.052 but was 1.044. I also used an efficiency calculator (Brewers Friend) which was telling me my efficiency was around 65%.

This is the problem with AG brewing - everyone gets different efficiencies so trying to replicate a recipe from someone else is so much harder because of all the variables. I would say it's more important to have repeatable effiiciency rather than a high efficiency, as you can plug that into your recipe calculator. Remember that having lower effiiciency just means you need to add a bit more grain, so it doesn't cost a lot - but you just need to know about it before you start the mash.

Efficiency can depend on a number of things but the biggest variable I've found is the grain source & crush. I'm currently getting 66% with the latest batch of grain from The Homebrew Company, Malt Miller's was the best I got around 72%, and I had one batch of grain from another supplier that was as low as 60%. Even batches of grain from the same supplier can vary as they are crushed at different times.

So don't worry about it too much, keep records of your brews and if you get 65% each time then plug this into your brewing app and it'll adjust the amount of grain to give you the target OG.

 

[Rodcx500z]

I brewed this morning brewzilla 3.1.1, 5kg of pilsner malt from crips water 22L mashed for 1 hour sparge 8L water that leaves me with 26.9L for the boil' og 1052

 

[Rodcx500z]

I do this recipe quite a lot and always hit the ball park 1050 1052

 

[Rodcx500z]

This is the hops after whirlpool using the paddle

 

[MrRook]

My efficiency went up when I got a grainmill and started doing it myself.

 

[MrRook]

The malt you get can also make a difference. Five pounds of my previous pale ale malt got me 1.040 in a three gallon batch. I got a bag of Crisp #19 floor malted maris otter and started getting 1.050.

 

[malhal]

Doing a mash out should give you the missing 0.008 because sugar stuck to the grains will release into solution when heated.

Full volume mash would be much worse because of diluted enzymes.

 

[MashBag]

around 5 - 6kg of grains. I mash in a 30L Brew Monk with 18L

That is a full load. It will compact.
You need to think about circulation flow and length of time.
Perhaps stirring might help.
Perhaps rice hulls
Perhaps a grinder (later), but I think you can get a lot closer before that.

I was wondering if a full volume mash would improve things or not.

Yes

 

[RoomWithABrew]

Check crush, check pH, measure gravity temperature corrected at end of mash, post sparge / pre boil and
Post boil.
Include volumes in your gravity and then you can work out mash efficiency, lauter efficiency and brew house.
Then you can find out where the efficiency can be tweaked.
If your sparge is quick then you have to consider channeling or not crushed enough.

 

[Agentgonzo]

That is a full load. It will compact.

Following from this, how well do you stir/mix your mash? Have you made sure you don't have and dough balls?

 

[Appleton Brews]

I usually get 75% brew house efficiency with my Mundschenk unless I make a wheat beer when it drops dramatically. I only buy crushed grain usually Crisp.
However stirring the mash is critical especially when mashing in to ensure no doughballs. I recirculate for the whole 60 minute mash and stir every 10 minutes. The grain to water ratio will also affect the efficiency, I now have a ratio of 3 to 1 I.e. for 5kg of grain then 15 litres of water. The dead space on the Mundschenk is 7 litres so recirculating the water is key, without a pump this difficult but it can be done manually. Sparring is also important as no sparge will lower your efficiency.

 

[foxy]

I am making mostly 4.5 - 5% IPA's Blonde Ale's and Pilsners which I make from either all grain kits or AG recipes and are generally around 5 - 6kg of grains. I mash in a 30L Brew Monk with 18L water - there is about a 4.5l dead space and I sparge up to 28L. I usually end up with 24L after boil

I am very careful with temp control and mash for 1 hour+ and same for boil. I check conversion with iodene and all seems good.

However I never seem to hit the expected SG - the last brew for example should have been 1.052 but was 1.044. I also used an efficiency calculator (Brewers Friend) which was telling me my efficiency was around 65%.

I get my grains crushed from Malt Miller so assume there would be no issue there so how can I improve this and should I bother - I don't care if the ABV is a bit lower than expected but if there are some things I can do it would be good - would improved efficiency improve flavour? I was wondering if a full volume mash would improve things or not.

Any advice welcome

Thanks

The thinner the mash the better the conversion. Grain crush, all the grain kernels have to be cracked for the enzymes to get to the starch, which is almost impossible without crushing the grain to fine.
I would do as suggested above and concentrate on consistency, try and improve on the lautering efficiency if you are happy with your mash temperature being stable throughout then I suspect the culprit is the lautering.
Full volume will improve the conversion of starch and keep a stable mash temperature throughout the mash period, mash out, and no sparge will arguably give you a better beer, evading any tanning issue. The only thing to be aware of is getting as much as the wort from the grain as possible.
You may need a little extra grain if you consider full volume but it is worth it.