Take Care With Hydrometer Readings

Dec 07, 2004 3 Replies

I just completed brewing an all-grain batch of a beer that the recipe said would read out at 1.070 for OG. Well, I thought I'd take a sample from the still-hot wort before cooling. My reading tube needs about 2/3 cup to accommodate the hydrometer and allow it to float. I immersed a ladle in the boiling wort, but it was resting on the immersion chiller I had already placed in the kettle to be sterilized, hence was just under the very top of the wort. After shutting off the heat, I measured out 1/3 cup, and carefully added another 1/3 cup water. I then put the measuring cup with the diluted sample in the freezer to get the temp down closer to room temp. When it was about



70 farenheit, I took a reading. 1.030, which owing to the one-to-one dilution was doubled for an actual read of 1.060. Now I don't mind being off by 2 or 3 points, but 10 points short told me something screwed up my read. I don't like to have to take a reading directly in the primary fermenter, but I really needed to know if my mash was uncharacteristically inefficient, or if my reading was off. I sanitized my hydrometer, took the lid off the primary, and let her float. Now I got 1.069. Much better. The conclusion I drew was that the sample from the top of the wort was weak owing to the heavier extract settling to the bottom. Next time I'll stir the wort before taking the sample. Passing this on to save others from making the same mistake.

Its funny, I was thinking my Maple Wheat was low too, came out 1.05 instead of 1.08. But given your story I think I may have made the same mistake. Thanks for sharing! A week in the Primary and now 10 days in the secondary and she's still making bubbles. (65F). My first wheat, so I'm pretty anxious to see how it turns out.

Dan, I've never done a wheat, so can't comment on why your fermentation is taking so long. I doubt, however, that you made the same mistake I did. In your case, the extract has almost all been fermented, and everything in the fermenter should be well mixed by that process. What I did wrong was to take a sample from the top of the wort in the kettle, in which case the more concentrated stuff had settled to the bottom. Also, if you're getting a reading below 1.010, the fermentation must be pretty thorough. My beers typically finish out at between 1.015 and 1.020, due to the non-fermentables in the wort. I'd be interested to know what temp you're at and what yeast you used. Also, how long after pitching did you get active fermentation?

I bottled it up last night, finished about 1.02, in the primary it fermented for about 7days, given the busy time of the year I moved it to the secondary to hold until I could get around to bottling and it started fermenting again, not madly, but evident by some occational bubbling in the airlock and some tiny bubbles rising to the top of the carboy. temp was about 65 and used a bavarian wheat yeast (dont have the name number in front of me).

This was my second all grain attempt, my first went so well, this one not so much. My extraction was not ideal, my strike temps were a little low, every batch is a lesson learned I suppose.

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