What's going on - low gravity?

[IPAman]

Brewed my 2nd AG today, an IPA. Took all my lessons from the first one and applied to this one, everything seemed to go OK. Hit my mash temp of 152, lost 1.3 degrees in 60 minutes. First runnings was 2g. from a 1.25 ratio, had 11 lbs of grain. Sparged with 6g , 180 degree water, stirred, set for 15 minutes, collected total 7.5g in brew kettle after 2nd running. My pre boil gravity was 1.032, did my 60 min. boil, cooled put in fermentor took OG and it was only 1.032. My estimate for an IPA should have been around 1.062. What did I do to get such a low OG?

 

[EdWort]

Poor crush on the grain. Did you crush it? Did you have any whole kernals?

Did you stir anytime during the mash?

 

[IPAman]

I collected 5g in the fermentor. The LHBS that I bought the grain from, crushed it for me, do not know what they did. After dough in I waited 5 minutes, stirred the mash, checked the temp, then let it set for the 60 min.
Batch sparged the 6 g, stirred for a couple of minutes then let sit for 15 min, before taking 2nd running.

 

[BrewMeister49]

stir the grain in immediately, and stir it for a while to eliminate dough balls in the mash. also have the LHBS double mill the grains and just add maybe .25 pounds rice hulls to your grain bill so you dont get stuck.

 

[mkling]

It is impossible, I repeat impossible, for you to have a pre-boil gravity of 1.032 and after a 60 minute boil have a gravity 1.032. You said you originally collected 7.5 gallons. Did you end up with 7.5 gallons? How much boiled off? One of those measures is wrong (I don't know which), but I wouldn't trust either at this point.

Now, either way, you're way off on your gravity. The Beersmith boiloff calculator says with a preboil gravity of 1.032 and a 60 minute boil that your SG ought to be 1.037. Not sure what the problem is. Could it be final volume? If the recipe was a 5 gallon recipe & you started with 7.5 gallons preboil, I'd bet you had ~6.5 gallons post boil.

 

[WorryWort]

It is impossible, I repeat impossible, for you to have a pre-boil gravity of 1.032 and after a 60 minute boil have a gravity 1.032.

Bang on! Not possible especially since your boil off rate appears to be about 33% (which is redonkulous!)

How warm was the wort with which you measured the SG? Was it cooled fully? I will bet $100 that it wasn't.

Most Hydrometers are calibrated to ~60F.

I made this mistake on my first AG.

 

[IPAman]

Well that was my thought too how you can end of with a OG the same as the pre boil gravity, but I checked my readings several times and that is what it said (believe it or not). Again, my pre boil volume was 7.5 g, my ending volume was 5g (had less then 2 qt in bottom of 15.5 keggle that I did not transfer). What are the main reasons for low OG , grain crush? amount of water used?

 

[WorryWort]

If it isn't that I must also agree with mkling - your volumes seem too high, or possible wrong. 7.5 is way too much collected wort for a 5 gallon batch at 60 minute boil. You will need to lose 33% in the boil and to hops to get 5 gallons.

Remember the amount you have in your kettle after you boil is what's important, not the amount you get into the fermenter.

My efficiencies did not get consistent until I really stressed accurate volume measurement. Also, diagnosing other problems is way harder if your volumes aren't consistent.

 

[jerryodom]

It really sounds like a combination of things went in to your poor performance. If I were you I'd go over a decent book or website and just try again. I know you've probably already did that but when you're in the middle of the process it's hard to self-evaluate on what you might be doing wrong. Really it's a practice makes perfect situation.

My primary problems when I was first doing AG were poor crush and poor sparging.

 

[EdWort]

I stir the grist every 20 minutes during the mash. I helps with hot spots and I get much better efficiency.

 

[IPAman]

For Noeldundas, I did know about the SG and temp, used Beer Recipator, Hydrometer correction calculator. For water volumes I used Brew365.com mash/sparge water calculator. Being my second AG I am still trying to dial in my equipment, it seems I am boiling off more then I estimate. First AG I used less water but ended up with 4.5g in fermentor, (my gravities were OK), I increased water volumes trying to compensate to get 5g at end of boil. Probably did use to much water, will dial back down on next AG, thanks for help. T.

 

[VagabondBrew]

I seem to have the same problem with IPAs, but not other styles, I hit perfect or slightly off. Today I got a preboil gravity of 1.035 and OG of 1.041. 152F mash for 60min and 7.5 - 8 gallons to boil. granted I took 6 gallons instead of 5.5 but since my target gravity was supposed to be 1.060 I doubt that extra half gallon lowered it that much.

My guess is not long enough mash time for conversion though I used the iodine and chalk method to check or improper water levels but didn't think it would throw it off that much.

I guess the other problem maybe was the milling of the grains? I use my own and milled this batch through twice because I know I have had ipa troubles.. oh well hope its drinkable.

 

[Beerfly]

Grain crush, dough balls, angry beer gods...none of this matters. The fact is you had less volume after the boil and that can only be from evaporation so your SG has to be higher. None of the other matters until you figure out why your readings are WRONG. I agree with the other poster about temperature, it changes hydrometer readings tremendously.