Decreased efficiency observations?

So over the past year I have noticed a “progressive” drop in my efficiency from 85% to 73% on both my systems ( EHERMS and 3 gal batch sparge/cooler). I can only assume that it is my crush because it is across 2 systems. I have a barley crusher for the past 4 years and have insured consistency with process and mill gap (.039). All other variables are “controlled” including water to grist at 1.75qt/lb, temp, time, mash schedule ( single infusion mostly), I mash out, I insure no dough balls and keep PH in a good range (I don’t think this has a big influence on efficiency?). My first runnings are normally around 1.070ish seems conversion efficiency is good?  Sorry so long it is just stumping me and I do have consistent efficiency and don’t really mind it being low but thought I would see what you guys/gals thought?

I just want to comment that if the pH is in or close to the normal range, it has little influence. If the pH is very high, >6, then efficiency goes down in a hurry with higher pH. That is from a talk I saw a while back.

Sweet! Thanks for the PH info always wondered how much it could effect conversion.

It’s difficult to tell from that picture, but I think you could probably crush a good deal harder than that.  Crush till you’re scared.  Crush until you get a stuck sparge on a batch, then dial it back slightly.  Crush as hard as you can without getting a stuck sparge.  That’s always the very first step in improving efficiency.

Which efficiency are you questioning, mash or brewhouse?

If brewhouse have you verified your brewing volumes from boil to package?

Brewhouse efficiency I suppose just because it seems my mash/conversion is fairly good 1.070 at 1.75qts/lb?  I have not verified my volumes all the way to packaging. I’ll need to think about that a bit not quite sure how that plays a role.

+1… I crush my grain until it’s about powder.

Brewhouse efficiency takes into account the entire process from volumes to gravities so if your volumes are off your total efficiency will suffer.

Example: you mash and hit your pre-boil volume and gravity say at 85%, you’re good, but then through the boil and chill you find your OG off and volume either high or low your brewhouse efficiency will be off of expected %.

If you have used the same mill and checked gap and have the same crush and mash process and water source then your mash efficiency should be consistent, if not then as mentioned start with the crush and pH, otherwise evaluate your post boil process and volumes/gravities

That crush looks like it could be a lot finer. Over time the bushings and bearings will start to wear and develop a little play. At these very tiny measurements it doesn’t take much to cause a change in crush. This could account for the difference you are seeing while maintaining the same gap. I eyeball my crush to where I want it and go by that not a gap measurement. I have also seen several people measure the same gap and come up with different answers to what that gap is. It is a real personal touch kinda thing.

Suffer??? The efficiency could certainly improve.
Also the second statement is not accurate either. The volume being off should throw off the gravity, but you can still hit the efficiency numbers. 60ppg in 5 gallons is equal to 50ppg in 6 gallons as far as efficiency is concerned in brewing terms.

Well the OP is trying to figure out why efficiency has gone down…

Your ppg numbers are correct but if youre throwing off your gravities because of incorrect volumes your total brewhouse efficiency % will be off from expected. Maybe we are just different on semantics?

I don’t think it’s semantics, but lets see. Total brewhouse efficiency is the total volume into the fermentor times the gravity divided by the total possible ppg from the grain bill(which is also the same divisor as mash extract efficiency). This is why total brewhouse is always less than mash efficiency(also called brewhouse efficiency-which does cause confusion).

Now the losses that occur are losses in volume. The gravity of this volume does not change whether you lose half of it or one tenth of it, it is your o.g.(post boil gravity). The losses which affect total brewhouse efficiency will come from the trub(hot n cold break) hops, dead space from chillers, spillage, etc. This is why if you hit your mash efficiency, your brewhouse efficiency has not been affected. So whether you ended with 6 gallons of 1.05 wort or 5 gallons of 1.06 wort into the fermentor your total brewhouse efficiency is the same, even though the volume and gravity changed. Total brewhouse efficiency can be thought of as mash extract efficiency times % of post boil volume that made it into fermentor.  Does this make sense?

The losses can effect the efficiency, I get that as you state, this effects volumes which is what I was getting at, you explained it more specifically, thanks

I never use fermentation vessel volume to calculate brew house efficiency because I do not collect every drop of liquid from my brew kettle.  I use post-boil volume minus the volume of the break and the hops, which means that I have to separate the liquid fraction from the hops and break for the portion of the wort that is left in the kettle.  It’s the only accurate way to assess one’s extraction rate or efficiency.

Mash efficiency + semi-accurate pre-boil volume is good enough for me.

Yep, agreed.

Well your beer must not taste very accurate. [emoji6]

I might have to write that on a score sheet sometime. Flavor: "Low to medium low effeciancy calculation accuracy on the finish. Try using a calculator, or for an historic taste use an abacus. "

precisely what i did…im at .028 mil gap now. 88% is norm now.