Help! Halfway through my first AG batch!

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rocketman768

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I am doing my first AG batch. I am using a recipe whose OG is supposed to be 1.056. However, after doing the mash and accounting for the temperature, the gravity reading was only about 1.035. What's up, and can I do something to correct it?

Batch size: 2 gallons
Grains: 3.3 lbs 2-row, 0.2 lbs crystal 60L, 0.5 lbs Munich 10L

For the mash: I heated my mash water to 160F and then ladled it into my grains and put that pot in the oven on warm. The original temp of the mash was 150, and after an hour in the oven, it was 160.

I am now boiling. Should I boil longer to reduce it some? Also, I am worried that there's just not a lot of converted sugar. It didn't taste very sweet, and sorta had a taste of oatmeal.

Thanks in advance!
 
How many gallons of water did you use in the mash? Did you sparge to rinse the remaining sugars?

At this point, yes, you could boil off some of the water to hit your target gravity. But, you will likely darken the wort more than you intended in the process.
 
Thanks for all your help so far.

I used 5.75 quarts of water in the mash (1.4 quarts per pound of grain), and I sparged with enough water (at 160F) to bring me up to 2.5 gallons for the boil. The sparging was done through a wire strainer with cheese cloth, and I slowly ladled the sparge water over the grains.

I ended up boiling it down to 1.5 gallons which put the final gravity at 1.045. I am really curious as to what I did wrong. I calculated the maximum gravity to be 1.099, so I only achieved about 45% efficiency.

Could I have shocked the enzymes somehow? Maybe the mash got over 170F at some point? Could my grains have been crushed wrong? I crushed them at the HBS by hand crank. I did one pass, and John Palmer's book says that's usually enough. I noticed that most of the grains looked like they were cut in half, and the husks were all separated.

Any ideas? I wanted to try AG because of the potential cost savings. My crappy 45% technique is definitely not achieving that goal.
 
Thanks for all your help so far.

I used 5.75 quarts of water in the mash (1.4 quarts per pound of grain), and I sparged with enough water (at 160F) to bring me up to 2.5 gallons for the boil. The sparging was done through a wire strainer with cheese cloth, and I slowly ladled the sparge water over the grains.

I ended up boiling it down to 1.5 gallons which put the final gravity at 1.045. I am really curious as to what I did wrong. I calculated the maximum gravity to be 1.099, so I only achieved about 45% efficiency.

Could I have shocked the enzymes somehow? Maybe the mash got over 170F at some point? Could my grains have been crushed wrong? I crushed them at the HBS by hand crank. I did one pass, and John Palmer's book says that's usually enough. I noticed that most of the grains looked like they were cut in half, and the husks were all separated.

Any ideas? I wanted to try AG because of the potential cost savings. My crappy 45% technique is definitely not achieving that goal.


I think sparging through a wire strainer/cheesecloth set up is probably to blame for the low efficiency. You might want to try batch sparging, which would be far more efficient. A fly sparge is what you attempted, sort of, but the grains are never dry, they are still submerged when you sparge. If you put the grains in your bottling bucket (lined with a grain bag), and added a gallon of 170 degree water and stirred well, then drained and did it again, your efficiency would probably go way up.
 
Honestly, there are a multitude of factors in AG brewing so it's often hard to point to a specific problem area.

All things being equal, without sparging, you still should have hit ~60% efficiency. Therefore, I'm leaning towards (1) mash temperature too high and/or (2) poor grain crush.
 
Honestly, there are a multitude of factors in AG brewing so it's often hard to point to a specific problem area.

All things being equal, without sparging, you still should have hit ~60% efficiency. Therefore, I'm leaning towards (1) mash temperature too high and/or (2) poor grain crush.

Hm. Did I at least do the right thing by ladling the mash water into the grain? I didn't shock anything right? I used an oil thermometer (for cooking oil) to measure the water temperature. That _would_ give the correct temperature right?

I'm also going to make sure I run the grain through my HBS' mill at least twice next time, or ask them what's up with the mill.
 
Brewing on such a small scale and being efficient takes practice. Mashing temperature has to be constant for enzymes to be able to work properly converting starch to sugar and that is hard to do without insulation and such a small mass volume. Sparging is also just as difficult because you need time to extract what little sugar there was. It would have to have enough grain depth to be effective if fly sparging so batch sparging would most likely a better choice for this small volume.
 
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