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jasonj
09-01-2009, 05:43 PM
Hey everyone,
I have a brew log up for my concord pyment...but I've run into a snag.

My primary fermentation vessel is a 5 gallon bucket, my batch is 3 gallons in volume.

The gravity has dropped low enough that the must no longer supports my hydrometer, it just sits on the bottom of the bucket.

I could take out a portion to test in a narrow tube, but at 3 gallons, if I test a few times a day I'll begin to seriously eat into my total volume shortly I fear.

Has anyone ever run into this problem and maybe come up with some novel solution?

Any suggestions are much appreciated.


Thanks!

Medsen Fey
09-01-2009, 06:03 PM
I often use a refractometer - a few drops of juice and I get a reading.

Still, there is no substitute for taking out samples and getting not only a clear reading, but a good smell and taste to help you learn to recognize the normal progression of fermentation. That way when one goes awry, you'll recognize it early.

jasonj
09-01-2009, 06:12 PM
I think you're right...a sample it is I suppose. I'll respond with some tasting notes in that case!

Medsen Fey
09-01-2009, 06:25 PM
And you don't need to test it several times a day. Once in a day is plenty for most fermentations.

I check daily during the first 1/3 to 1/2 of fermentation while aerating and adding nutrients and so forth. After that, I usually seal it up and check it when I think it's done (and afterward to confirm the gravity is unchanged as required.)

jasonj
09-01-2009, 06:57 PM
And you don't need to test it several times a day. Once in a day is plenty for most fermentations.

I check daily during the first 1/3 to 1/2 of fermentation while aerating and adding nutrients and so forth. After that, I usually seal it up and check it when I think it's done (and afterward to confirm the gravity is unchanged as required.)


That makes sense. I had been checking the gravity twice daily as it was easy to do...but now, once a day it is. 1.068 is today's magic number by the way...so I think things are moving along rather well. Thanks for the advice.

akueck
09-01-2009, 11:52 PM
Has anyone ever run into this problem and maybe come up with some novel solution?

Yes! Answer: make more mead! ;D

Sasper
09-01-2009, 11:54 PM
Call me crazy, but instead of throwing out or should I say drinking so many samples I just sanitize my test tube and hydrometer and turkey baster in Starsan and pour it back in when I'm done. I know it's dangerous but I have yet to have any problem whatsoever.

wildoates
09-02-2009, 12:14 AM
I do my gravity checking in my thief, and I too let it dribble back into the carboy when I'm done. No way I could drink it all.
:drunken_smilie:

akueck
09-02-2009, 12:38 AM
I used to return samples to small batches, but my hydrometer jar is pretty beaten up at this point. I consider it "unsanitizable" and thus all samples get consumed/drained. Not worth the risk IMO.

Dan McFeeley
09-02-2009, 01:30 PM
Another way of monitoring the SG of a fermenting must is to simply weigh the carboy, then calculate the SG from the weight changes. More details are at this link to the thread:

http://www.gotmead.com/forum/showthread.php?t=7453

The advantages are being able to check the gravity as often as you like, without having to open the carboy. Disadvantages are the moving back and forth of a heavy carboy, the weight changes in a small batch like 1 gallon are too small to measure, and an error factor creeps into the calculations from evaporation of moisture content and loss of volume from escaping CO2.

Even with the error factor, you still get a ballpark figure that will allow constant monitoring of the fermentation since it's the dynamic changes you're watching more closely than the exact figure.

wildoates
09-02-2009, 01:51 PM
And my students tell me they have no real-life application of d=m/v!

akueck
09-02-2009, 03:48 PM
And my students tell me they have no real-life application of d=m/v!

"Weigh your booze" is probably not something you want to encourage the kiddies to practice. ;) How about a field trip to Salt Lake? That's some fun with density.

I think the weight thing could work with one gallon batches. I have a common kitchen scale that will measure 5kg in 1g increments. 1 gallon of must plus jug will come close to the limit but there is about 3/4 pound difference between a gallon of 1.100 and 1.000 liquid. The sugar breaks would come out to about 4 oz difference, which is definitely noticeable. Next time I brew something up I'll do this. I'll also see what I get on the meads I have at the halfway point now. Yay science!

AToE
09-02-2009, 05:00 PM
I might try that myself with my 1 gallon batches, and I'll take hydrometer measurements too just to see if I'm getting the right numbers. I'd love to skip taking hyrometer measurements until the end, it makes me nervous about contamination.

Pewter_of_Deodar
09-02-2009, 05:20 PM
Has anyone ever run into this problem and maybe come up with some novel solution?


I chuckled when I first read about multiple readings a day. Those small lines on the hydrometer tend to blur a bit after the 20th sample that day. *grin*

As far as one solution, get a miniature hydrometer and leave it in the batch. They are a buck or two...

Medsen Fey
09-02-2009, 06:21 PM
As far as one solution, get a miniature hydrometer and leave it in the batch. They are a buck or two...

I tried that before, but I found the scale was very compact and hard to read through the carboy.