OG short by about .06

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Pickngrin

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I brewed an all grain steam beer today. My pre-boil OG was dead on with what Beersmith calculated, but my post-boil OG was ~ 1.046 when it should have been 1.052. The calculated bitterness ratio was .829.
Of course, the problem was that not enough water evaporated during the boil. But I'm not sure why. Ever since I started using Beersmith a few months ago, I've been so much more successful hitting target gravities. Not sure how my evaporation rate was off as it was today. Any ideas?

Also, do you think that this beer is going to be very different at 1.046?

Thanks
 
I cannot tell you, but the same thing happened to me on my last batch. Normally I hit my target volumes and gravities right on the money, but the last one just didn't boil off as much as expected. I ended up having 3/4 of a gallon more than I planned for and the batch size was only 2.5 gallons. (!)
 
Temperature changes and altitude can affect boil off rates. And no, your beer won't be much different with a .006 difference.
 
I just brewed my Xmas Ale this morning and discovered that my post-boil OG was 1.042 (way down from 1.052) due lack of evaporation during boil. Couldn't get a good 7gal rolling boil going with the house windows open and cold weather. Have to keep the windows open or the wife complains of the smell. So, not much choice there. I did a lot better with an Irish Ale two weeks ago, hitting 1.050 (expected 1.052) with much warmer weather.

So, my question is... should I boil a lesser amount and add cold water at the end? or boil longer? If I boil longer how does this effect my hops additions?

TIA
 
From what I've read, hops additions have little effect on the beer after 60 minutes. So....if you used bittering hops at 60 minutes, then later in the boil decided you needed to boil longer, it probably wouldn't make much of a difference. As long as you keep your aroma and flavor hops at the right times.
 
Metal braid + thermometer = ??

It's the metal braid that connects the digital thermometer unit to the probe. When it gets wet, the thermometer readings becoming wildly inaccurate. I believe that I may be able to dry out the braid to fix the problem, hopefully.
 
I dont think you want to collect less preboil volume. Doing this will worsen your issue and you will have less sugars post boil. I collect more and boil for 90 minutes or until I reach my target volume. I make notches/markings on my spoons/paddles so that I know where 5g, 6g,7g and 8g are at in the kettle. The only time it gets tricky is with additions of flavor /aroma hops at 15 minutes, but its not a big deal. If I get close to target volume, I just put in the the immersion chiller, add flavor hops addtions and stop after 15 minutes. Its all part of refining your process. The point is that you shouldnt be surprised when transferring to the carboy that you've boiled off less, you should know this prior to flame out and be able to make adjustments.
 
Different weather affects the rate of evaporation. If you brew outside in Connecticut I would imagine that the colder weather, wind blowing, and your elevation would all effect how much you boil off.

As far as the few points of gravity are concerned, next time throw a cup or two of LDME in there if the gravity is of that much importance.

I'm sure the beer will be great, just won't have quite as much ABV as it should have.

Also, is your boil of the hard rolling variety or when it just starts to boil you back off on the heat a little bit? This can make a big difference as well.
 
I dont think you want to collect less preboil volume. Doing this will worsen your issue and you will have less sugars post boil. I collect more and boil for 90 minutes or until I reach my target volume. I make notches/markings on my spoons/paddles so that I know where 5g, 6g,7g and 8g are at in the kettle. The only time it gets tricky is with additions of flavor /aroma hops at 15 minutes, but its not a big deal. If I get close to target volume, I just put in the the immersion chiller, add flavor hops addtions and stop after 15 minutes. Its all part of refining your process. The point is that you shouldnt be surprised when transferring to the carboy that you've boiled off less, you should know this prior to flame out and be able to make adjustments.

I do use a marked dowel to assess volume, and I did realize that I had a bit more than usual left in the kettle (although as you implied, the displacement from the immersion chiller affects that), but I suppose that I was ignoring the signals, possibly because I wanted to wrap up the brew day. Lesson learned for future brew days.
Thanks
 
Different weather affects the rate of evaporation. If you brew outside in Connecticut I would imagine that the colder weather, wind blowing, and your elevation would all effect how much you boil off.

As far as the few points of gravity are concerned, next time throw a cup or two of LDME in there if the gravity is of that much importance.

I'm sure the beer will be great, just won't have quite as much ABV as it should have.

Also, is your boil of the hard rolling variety or when it just starts to boil you back off on the heat a little bit? This can make a big difference as well.

I'm not worried about the alcohol content so much, just want to get some great results. As for the boil, I usually back off of the hard rolling boils so that it's steady. I think for the future I'm just gonna let err rip since I'm usually boiling 6.5 gallons in a 10 gallon brew pot.

I dont think you want to collect less preboil volume. Doing this will worsen your issue and you will have less sugars post boil. I collect more and boil for 90 minutes or until I reach my target volume. I make notches/markings on my spoons/paddles so that I know where 5g, 6g,7g and 8g are at in the kettle. The only time it gets tricky is with additions of flavor /aroma hops at 15 minutes, but its not a big deal. If I get close to target volume, I just put in the the immersion chiller, add flavor hops addtions and stop after 15 minutes. Its all part of refining your process. The point is that you shouldnt be surprised when transferring to the carboy that you've boiled off less, you should know this prior to flame out and be able to make adjustments.

Thanks. These are great tips, never even thought about notching the spoon (duh). This is my fourth all grain attempt and because my process was exactly the same as my last recipe (water and grain volumes) I didn't pay as much attention to this detail. Just expected the same result. It's a learning experience for sure. I will definitely start taking better note of the volume and adjust accordingly.
 
So, I couldn't leave well enough alone... this evening, I boiled about 1# of light DME, cooled it, and added it to the fermenter.
Some would call this a sickness...others would call it being a homebrewer.
 
Some would call this a sickness...others would call it being a homebrewer.

No, it really is a sickness. ;)

Hey, at least you didn't do what I did - forgot how to count while adding water with the help of my handy 1/2 gallon pitcher. Frankly, the notched spoon or mash paddle mentioned above seems high tech compared to some of my "process".

:tank:
 
No, it really is a sickness. ;)

Hey, at least you didn't do what I did - forgot how to count while adding water with the help of my handy 1/2 gallon pitcher. Frankly, the notched spoon or mash paddle mentioned above seems high tech compared to some of my "process".

:tank:

Haha...that seems to happen to me every time I'm filling up a kettle with water...
 
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