Abysmal Mash efficiency

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

Teufelhunde

Well-Known Member
Joined
Jan 4, 2020
Messages
378
Reaction score
302
OK, so I have a total of three all grain brews under my belt. I am brewing with a Brewzilla 3.1.1. First one was an IPA recipe by David Heath (you may have seen his YT channel). I hit just 1 point below all the numbers, which put my mash efficiency close to 75%. The second was a Citra Maris Otter Smash that I found on Brewfather. Didn't do so good this time, came in around 64%. Brewed #3 today(a purchased kit from morebeer) and got a whopping 59%(had to add 2 lbs DME to get up to OG).

On all three batches, I used the same processes, I did use the top screen in the mash pipe and used the recirc during the mash. I didn't have a PH meter for the first two, but according to brewfather, I should have been in the ballpark. On the third I used a cheap POS meter that I don't trust, but again, it said I should have been around 5.25.

I need to get this nailed down so I can have a relatively consistent efficiency, and, of course, a higher, consistent efficiency would be preferred over a lower, consistent number.

I figured on the next couple of batches to make a couple of changes....

1) 90 minute mash -- give it just a bit more time

2)Leave the top screen off so I can stir the mash every 10-15 minutes. I have a diffuser that I can put on the tubing to still be able to use the recirc pump and spread the flow out over top of the grain bed.

3)I turned down the quarts/lb ratio in brewfather a bit, as I noticed on the last one that the mash was really soupy (had about three inches of wort above the grain bed)


I was going to try these three changes for the next couple of brew days to see what happens, then change one thing at a time from there on and take note of the results.

While I am making wholesale changes, doe anyone have any suggestions?

TIA for any input

Lon
 

RM-MN

Supporting Member
HBT Supporter
Joined
Nov 26, 2010
Messages
15,118
Reaction score
6,219
Location
Solway
I need to get this nailed down so I can have a relatively consistent efficiency, and, of course, a higher, consistent efficiency would be preferred over a lower, consistent number.
The biggest factor by far that influences mash efficiency is the milling of the grain. If you want consistently high efficiency, buy a mill of your own. It doesn't need to be a fancy mill, a cheap Corona style will be just fine. With your own mill you can buy unmilled grain in bulk and it doesn't take a lot of batches for the difference in the price of the grain plus the reduced amount of grain needed with the higher efficiency to pay for a mill.
 

CascadesBrewer

Supporting Member
HBT Supporter
Joined
Mar 24, 2013
Messages
2,296
Reaction score
2,185
Location
VA, USA
Check out this video from MoreBeer:
Mash efficiency

Mill gap is VERY important

I am a MoreBeer fan and customer, and I appreciate this video...but man I have seen so many pictures of grain from MoreBeer that looks like they just waved it near the mill. With the popularity of BIAB and similar all-in-one systems, more stores need to have options for finer crushed grain. My first recommendation for a BIAB brewer is to get your own mill. If not, find a supplier or local shop that provides the option for a finer or double crush.
 

Wayne1

Well-Known Member
Joined
Mar 12, 2008
Messages
1,444
Reaction score
494
Location
Littleton, CO
The video is a good explanation of what can change your efficiency. I, personally, do not recommend buying pre-milled grain from anyone. Spend some money and buy a decent mill. Carefully monitor what the mill gap is for each type a grain you mill. You will eventually find the sweet spot for your type of brewing.

I use a 60L Brewzilla and brew 5 gallon batches with no sparging. I average 70% CONSISTENTLY. That is fine with me and my numbers remain the same. I can improve them a bit with step mashing and a bit more with decoction. But for most of the beers I make, single infusion with mash out works.
 

renstyle

Supporting Member
HBT Supporter
Joined
Aug 20, 2020
Messages
444
Reaction score
504
Location
Central Iowa
I'm with the other fine respondents: grain mill gap/grain milling fineness.

Since it wasn't mentioned in the OP it was the first thing I thought of as well.

Mash temp is the second variable I would focus on. 149F/65C for better (more) fermentable sugars all the way up to 155F/68C.
 

pvtpublic

Whale Oil Beef Hooked
Joined
Feb 19, 2011
Messages
421
Reaction score
290
Don't forget about your flow rate, make sure you crack your valve slowly so it doesn't compact your grain bed when the wort rushes out. Then recirc and lauter nice and slow.
 
Top