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gravity reading way too low! How did this happen??

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amcclai7

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I feel embarrassed asking this question given how many batches of beer I have brewed but here goes.

I brewed an IPA a few days ago. Grain bill = 1lb vienna, 1lb munich, 7lbs DME. OG was supposed to be right around 1.060. I did a three gallon boil and I was supposed to add between 2 - 3 gallons of ice cold water in order to reach the total volume and in order to chill the wort. Well, I added 2 gallons and checked the gravity. I figured it would be around 1.070 or so and from that I could determine exactly how much water to add.

It was 1.045!!!

WTF!!! How could this happen? Even if the efficiency on the specialty grains was low (which it shouldn't have been i mashed them at 154 for an hour) there is no way that the gravity would have been that low. The DME itself would have produced a much higher gravity than that. What I am thinking might have happened was this: I finished the boil and added one gallon to the kettle to help cool it before transferring to the carboy. I added that mixture to the carboy and then about a minute later poured a gallon of water on top of that. I didn't shake or swirl the carboy. Instead, I immediately poured a sample from it into a hydrometer beaker and tested that. I'm thinking maybe since I poured the sample out of the top of the carboy that it was water heavy and that made the hydrometer reading off. Is that possible?? Have you heard of this before?

Any help would be appreciated!

P.S. i checked my hydrometer against pure water and it was dead on. Also, I did temperature correct my reading. It the reading was actually 1.040 but at 100F that translates to 1.045.
 
No worries brew buddy you will still have beer by the end of the day!

Now to clarify, you said you mashed at 154 the specialty grains. By this you mean you were steeping the grains and only extracting flavor and color from those specialty grains.

To mash would include to sparge and rinse your grains. You would have extracted very little fermentable sugars to really not make it worth it. All of your fermentables in this recipe will be from your DME you added.

In a quick calculation 7 lbs of dme in a 5 gallon batch would give you that target OG 1.060. You said you calibrated your hydrometer using pure water would this be RO water or distilled water? I would get a gallon of distilled just to make sure and calibrate it at 60 degrees F.

When you do Extract batches you do have concentrated wort prior to adding the extra "top off water". When I used to do this I too had issues with some batches. For the most part the mixture wasn't mixed well enough. If you would have shaken the carboy prior to pulling the sample you might have had a higher reading. No matter you will still have the same characteristics of the actual recipe. The yeast will still eat the fermentables no matter if it was concentrated at the bottom of the carboy or top eventually it will equal out.

The only downer would be you dont have a very reliable reading for you OG. But again no worries relax and have a home brew!
 
you probably got lousy mixing of the cold water and wort and wound up with a denser layer below at 1.090 and a layer on top at 1.045. The yeast will stir it up when it gets going and my guess is if you measure after fermentation kicks off it will be higher than the current reading or read 1.045 after a couple days of actively fermenting
 
As others said, Extract is really hard to screw up.

if you added all of the extract, and ended up with the proper volume going into the fermenter you would have to be a wizard to not get the right gravity. Steeping grains for color wont change that.
 
I'm thinking maybe since I poured the sample out of the top of the carboy that it was water heavy and that made the hydrometer reading off. Is that possible?? Have you heard of this before?

Yes. Your wort wasn't evenly mixed, so the specific gravity at different spots in your carboy was different. Diffusion and yeast activity will even it out with time.
 
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