Brewhouse Efficiency Tips

The only other thing I can think of is the difference in ambient temperature when mashing. Last time I brewed back in early September it would have been about 14 or 15c - yesterday it was more like 7 or 8c. Additional heat loss through the mash tun? Still, strike water was actually hotter this time (to compensate for the colder grain starting temp) so I can't think that would have a massive effect.

I'm sure once it's ready to drink it'll be obvious whether the measurements were out - except for some additional sugar, this is the same recipe I brewed for my previous batch. I've kept one bottle back from that batch to do a side-by-side comparison - if there's a noticable difference in strength, I'd like to think I could detect it by taste. If the reading I took this time is to be believed, the additional sugar made no difference (which is ridiculous unless my conversion efficiency fell off a cliff) and I'll end up with two very similar beers, both at about 4.2%. I was aiming for about 5.1% this time round...
 
I brewed another batch; this time I got a brew-house efficiency of 70%. Conversion efficiency increased to 83%. Kinda funny story. I miscalculated my mash tun's ability to hold 4 gallons of mash water with 12 lbs of grain. As I mixed my grains into the mash tun and the thing started to overflow, I ladled a bunch out and put in a separate pot and decided to introduce myself to decoction mashing. the whole mess dropped my initial mash temperature down to about 144F. So decoction would help that out. Spending about 45 minutes slowly heating to a boil my decoction, I returned the decoction to the mash (about 75%), and the temp was about 152F. I let sit for another 40 minutes before sparge. I did use higher sparge water temp. Maybe that helped. The majority of the grain bill was Maris Otter malt, so I doubt the decoction helped at all, but the decoction smelled very unique. Should add an interesting (hopefully good) note to the beer's flavor.

So finally, my pre-boil efficiency (using gravity reading + wort volume collected) was 63%, but the final brew-house efficiency was 70% (using final wort volume and after boil gravity reading (correcting for temperature).

How can you get a higher efficiency after boil, assuming you add no sugars to the wort during the boil?
 
Sounds like you had an adventure on brew day!

TheZel66 said:
How can you get a higher efficiency after boil, assuming you add no sugars to the wort during the boil?
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In theory that isn't possible, so it must be a volume or gravity measurement issue. Make sure your gravity and volume readings are temperature corrected. If you are sure they are correct, post them and we'll take a look. 7% is a lot. I would expect it to vary by ~1-2% at the most due to rounding/measurement errors.

Did the recipe have any raw sugars/extracts? The brew stats logic assumes you have added all these by the end of the boil - but not at the time you took your pre-boil gravity.
 
Nope, it was all grain, and my volume measurements were pretty accurate. My guess is I botched one of my gravity readings. I'm using White Labs California Ale yeast, which has been pretty consistent in terms of fermentation attenuation percentage, so when I take a final gravity reading, I'll have a better idea which was the correct gravity. thanks
 
Were you using a refractrometer? I am about to junk mine, the readings are all over the place. Sometimes it matches my hydrometer, sometimes it is + 0.005. Haven't figured it out yet, it doesn't appear to be temperature dependent.

I may invest in a precision set of hydrometers next (one for measuring OG, and one for FG).
 
LarryBrewer said:
Were you using a refractrometer? I am about to junk mine, the readings are all over the place. Sometimes it matches my hydrometer, sometimes it is + 0.005. Haven't figured it out yet, it doesn't appear to be temperature dependent.
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You may want to experiment with some sugar solutions to see how it reads a well defined solution:

10g table sugar + 40g water = 20 Brix

add 40g water to that = 10 Bx

add 80g water to that = 5 Bx

also check 0 setting with water (ideally very low mineral water, But I think that's standard in OR)

I may invest in a precision set of hydrometers next (one for measuring OG, and one for FG).
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That is also a good idea. But the refractometer should not be as erratic as you report. Check 0 before each measurement. I have to do that on mine even though it is supposed to have ATC.

There is not much in a refractometer that can cause erratic readings. Those things are pretty darn simple.

Kai
 
TheZel66 said:
How can you get a higher efficiency after boil, assuming you add no sugars to the wort during the boil?
Click to expand...

If you need to cool the sample, make sure to cool it in a closed container. Evaporation can be significant enough to raise the sg by a few points.

It's also possible that your pre-boil reading was taken from a wort that was not well mixed.

Kai
 
Kaiser said:
You may want to experiment with some sugar solutions to see how it reads a well defined solution:
...
Click to expand...

Good tips. I'll give it a shot in the near future and let you know.
 
Every time I take a reading with my refractometer I calibrate it with distilled water. Usually I don't have to mess with it but I always have the same baseline. I do have hydrometers nd I put them in distilled water as well.
 
I batch sparge, and generally don't follow any of the water to grain laws. I normally just do about 3 gallons of water for each run for a total output of around 7.5 gallons of wort which boils down to about 5.5 gallons. Am I making a terrible mistake? Your input is greatly appreciated!
 
If you enter brew logs and track your volumes and gravities along the way you can dial in the process. Bigger beers with more grain will require more water due to grain absorption. Same thing for hoppy beers, depending on your brewing process hops soak up wort and lower efficiency.

I tend to be obsessed with the numbers, and their meaning.

Buy hey, RDWHAHB!
 
As it turns out, and after reviewing my brew day notes, I forgot to correct the temperature on the pre-boil gravity reading. Doing so changed it from 1.044 to 1.047, which is more in line with what expected from a 1.062 after boil original gravity, at least within a +/-0.001 margin of error.
 
TheZel66 said:
As it turns out, and after reviewing my brew day notes, I forgot to correct the temperature on the pre-boil gravity reading. Doing so changed it from 1.044 to 1.047, which is more in line with what expected from a 1.062 after boil original gravity, at least within a +/-0.001 margin of error.
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And math is saved!

(I had a math teacher who was fond of saying that after filling a chalk board with equations, and after 10+ minutes of scribbling, getting the expected result.)
 
SoundersFC said:
I batch sparge, and generally don't follow any of the water to grain laws. I normally just do about 3 gallons of water for each run for a total output of around 7.5 gallons of wort which boils down to about 5.5 gallons. Am I making a terrible mistake? Your input is greatly appreciated!
Click to expand...

I do roughly what you're doing - it all turns out fine in the end.
 
Another thing I've discovered that causes efficiency to drop is excessive humidity.

Try getting a proper boil-off rate in the middle of a rain storm!

I was inside in case you're wondering...
 
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