Efficiency crazy higher than expected

[Trail]

I have a new kit that I've brewed on three times. Yesterday I brewed a recipe that I had Beersmithed at 65% mash efficiency... only to find I hit 94.9% mash efficiency. I'm trying to figure out where to go next.

My gear consists of:

• Fermenter's Favorites 7 gallon mash tun with Titan false bottom
• Grains milled by Northern Brewer
• Thermapen Mk4

My water profile is:

• PH 7.30
• Calcium 9 PPM
• Magnesium 2 PPM
• Sodium 28 PPM
• Chloride 41 PPM
• Bicarbonate 33 PPM

I don't have great data on the baseline efficiency on my setup. This is the third AG batch I've done... the first batch was wrecked by my breaking my only hydrometer, but it came out much bigger than I expected, booze/malt-wise. The second batch used two-year-old grain and I didn't sparge, and it still hit 60%.

My questions are:

1. Where is my crazy efficiency coming from?
2. Should I plan my next recipe for 94% efficiency as well, or should I pick an intermediate value?
3. Is there such a thing as having too high an efficiency?

 

[pricelessbrewing]

95% mash efficiency is extremely high. I would be skeptical of the measurements if you're used to getting 65%.

Can you please provide the recipe and all measurements you took on brewday?

 

[Pintabone]

I had a similar experience with my second AG batch where I had calculated a 98% efficiency in Beersmith. Turns out it was because I didn't mix the first runnings with the sparge wort when taking the sample out of the ball valve at the bottom of the kettle. Did you stir the kettle to mix prior to pulling a sample?

 

[Smellyglove]

This is about 100% due to error in measurment.

 

[Trail]

I did the math a couple times on brewday to be sure, but more eyes on it are great. Malts are:

6 lb Maris Otter
0.5 lb Biscuit
0.5 lb Caramel 120l

Pre-boil I had 7.75 gallons of wort measuring 1.020 @ 130 Fahrenheit, which I calculated would have read 1.032 @ 60F where my hydrometer is calibrated.

Regarding:

I would be skeptical of the measurements if you're used to getting 65%.

As I said in the first post, this is my first batch on the equipment where I've sparged... except for the first batch in which I broke my instruments and didn't get readings. Prior to this equipment I was doing BIAB using different water so I do not have any kind of baseline for what I'm brewing on now.

 

[Smellyglove]

If you sparge and take a reading from the kettle after sparging unless you know the quirks many people do get very high gravity readings, which are incorrect.

 

[Trail]

I had a similar experience with my second AG batch where I had calculated a 98% efficiency in Beersmith. Turns out it was because I didn't mix the first runnings with the sparge wort when taking the sample out of the ball valve at the bottom of the kettle. Did you stir the kettle to mix prior to pulling a sample?

This seems plausible, but I'm not sure it happened in this case. I don't remember stirring but the grain bed was good enough in the grain bed that I opened the ball valve most of the way. And then I carried the kettle to the burner stand 10 feet away before I poured my sample.

But still, I could see that nudging the gravity down... hrm.

I diluted the boil a bit (around a half gallon) to help compensate for the unexpectedly high gravity. I didn't do more because I was second-guessing my math at the time and didn't want to thin it out too much in case I was wrong... but even so I ended the brew day with a little over six and a half gallons of wort that measured 1034 after temp correction.

 

[doug293cz]

I did the math a couple times on brewday to be sure, but more eyes on it are great. Malts are:

6 lb Maris Otter
0.5 lb Biscuit
0.5 lb Caramel 120l

Pre-boil I had 7.75 gallons of wort measuring 1.020 @ 130 Fahrenheit, which I calculated would have read 1.032 @ 60F where my hydrometer is calibrated.

Regarding:


As I said in the first post, this is my first batch on the equipment where I've sparged... except for the first batch in which I broke my instruments and didn't get readings. Prior to this equipment I was doing BIAB using different water so I do not have any kind of baseline for what I'm brewing on now.

A 7 lb grain bill with 7.75 gal pre-boil is a pretty small beer, which should translate to very high lauter efficiency. With 100% conversion efficiency and a single, equal runnings batch sparge, my simulator spits out a mash efficiency of 93.8% and a pre-boil SG of 1.030. A multiple batch sparge or good fly sparge could easily exceed these numbers.

Brew on