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General Category => Equipment and Software => Topic started by: flbrewer on May 26, 2013, 05:13:36 PM

Title: Hydrometer wort testing temp question
Post by: flbrewer on May 26, 2013, 05:13:36 PM
I've pulled a sample of wort just before pitching and it's sitting in the hydrometer test tube at about 73 degrees. Should I place the sample in the refrigerator to bring it closer to 59 or just adjust the math?
Title: Hydrometer wort testing temp question
Post by: In The Sand on May 26, 2013, 05:21:43 PM
Either way. You can put your temp values and hydrometer reading in beersmith and it'll correct it for you.
Title: Re: Hydrometer wort testing temp question
Post by: a10t2 on May 26, 2013, 05:33:17 PM
Once you're within 30°F or so you can effectively compensate for temperature. Add 0.0015 in this case.
Title: Re: Hydrometer wort testing temp question
Post by: flbrewer on May 26, 2013, 05:46:32 PM
Does 1.038 sound low for SG? (I did add 2.5 gallons top off, so maybe it wasn't mixed up enough?
It's this recipe...5 gallon batch, extract.

7 lbs Muntons extra light DME
1 oz Warrior or Magnum hops (60 min)
2 oz Amarillo hops (10 min)
2 oz Amarillo hops (0 min)
Safale US-05
*added 1.5 pounds of specialty grains as well
Title: Re: Hydrometer wort testing temp question
Post by: klickitat jim on May 26, 2013, 05:51:08 PM
Should be much higher I would think. Like 1.060 ish
Title: Hydrometer wort testing temp question
Post by: flbrewer on May 26, 2013, 05:54:44 PM
Should be much higher I would think. Like 1.060 ish
That sucks. I did add specialty grains, would that matter?

Too late to check again since I pitched about an hour ago?
Title: Hydrometer wort testing temp question
Post by: duboman on May 26, 2013, 06:04:05 PM
It's probably a bad mix, when doing extract batches and hitting your volumes it's just about impossible to miss the expected OG because its pretty fixed by the amount of extract used. 1lb of extract is 45 gravity points

45x7=315/5=63 so OG is 1.063 regardless of what you read with the hydrometer.
Title: Hydrometer wort testing temp question
Post by: flbrewer on May 26, 2013, 06:10:30 PM
I did drop some of the DME, maybe a cup. Not sure this would make that much of difference. Is it worth checking again or should I let it be? Also, is there a way to check the ABV if I never had the SG correct?
I'm guessing I sucked up a lot of the Starsan foam with my sample as there was an enormous layer on top of the beer. The turkey baster barely hit the top of the beer. Next time I have to use a thief.
Title: Re: Hydrometer wort testing temp question
Post by: klickitat jim on May 26, 2013, 08:04:11 PM
That may be the issue. If it were me I would go with 1.060 as your OG when it's time to calculate ABV. It's going to be a rough EST but who cares, right? You'll have about 6.5 beer.

So next time just be cautious to take your sample once it's well stirred and whatnot
Title: Hydrometer wort testing temp question
Post by: duboman on May 26, 2013, 08:08:35 PM

I did drop some of the DME, maybe a cup. Not sure this would make that much of difference. Is it worth checking again or should I let it be? Also, is there a way to check the ABV if I never had the SG correct?
I'm guessing I sucked up a lot of the Starsan foam with my sample as there was an enormous layer on top of the beer. The turkey baster barely hit the top of the beer. Next time I have to use a thief.

The cup of DME probably won't mean much so go with 1.062-3 for OG.

ABV will depend on your final gravity:
(OG-FG)/(OG-1)=x/100=%
Title: Re: Hydrometer wort testing temp question
Post by: a10t2 on May 26, 2013, 08:36:34 PM
Yeah, you can't get an accurate SG once you add the water. At least, not without an unreasonable amount of shaking. You can measure the concentrated wort and then account for the dilution, or you can just calculate the SG based on the potential extract (~43 point-gal/lb for DME). If your mass and volume measurements are reasonably precise, you can calculate the SG better than a cheap hydrometer will measure it.
Title: Hydrometer wort testing temp question
Post by: flbrewer on May 26, 2013, 09:41:27 PM
Thanks everyone!