calibration for priming

I don't know why, but I've always used honey as my priming sugar in the past. I know, I know... But using Papazian's 1/2 cup per five gallon batch hasn't caused either an infection, bottle bomb, or flat beer yet.

To ensure continuing good luck, the experimentalist in me says that I should measure the sugar content of my honeys so that I can add precisely the correct amount.

If I combine accurately weighed amounts of sugar and water, I could create a calibration curve that illustrates the relationship between sugar content and gravity. Then I would only have to measure the gravity of my honey to get the sugar content. And I know that I want 2/3 cup cane sugar normally, so by doing a little unit conversions it would be pretty easy to figure out how much honey that should be.

Sounds like a lot of work, yes, but for now I like being counter-cultural in my use of honey.

From what I know, this experiment should work. Has anyone ever tried this before or does anyone see a problem with it?

Are you going to thin the honey to measure the gravity? It seems awfully viscous to stick your meter into. You'd need a proportion correction then I would guess (but I am really not sure how that would work). I was reading(http://www.fao.org/docrep/w0076e/w0076e04.htm ) that honey is usually in the range of %95 to %99 sugar(s) (mostly fructose and glucose) (although one source claims it is %75 fermentable in your beer http://www.realbeer.com/spencer/FAQ/sugar.html). And the gravity is affected mostly by RH as it is highly hygroscopic so it seems to me that you have two factors working here, the % of moisture absorbed into the honey and the amount of fermentable sugars present in the honey. I believe, correct me if I am wrong, that the gravity is not merely determined by fermentables alone. I am fairly certain in the case of sugar, that it is probably nearly %100 fermentable by the yeast, but with the honey there are other constituents that are not fermentable which can contribute to the the gravity (albeit slightly). That all being said, you would have to test every single time you opened a jar of honey. Imo it seems like quite a bit of work, but if you did it properly and carefully you may have some good info to contribute to other honey primers.

Sorry to revive an old thread, but I have some new information.

Just in case anyone was wondering, I performed the above experiment tonight and determined that it doesn't work.

I created a calibration curve that plots weight percent sucrose against specific gravity. The r^2 value is 0.97, which isn't bad considering that I'm doing this at home.

When I tried to convert my gravity reading of a 10.9% honey solution (by weight) into percent sugar, I got the impossible result of 134.2%.

It was a good idea, but experimentally it was just not to be...

Harold McGee, whose authority I trust, says in On Food and Cooking that the composition of a typical honey is:
water: 17%
fructose: 38%
glucose: 31%
sucrose: 1.5%
other disaccharides: 7%
higher sugars: 1.5%
acids: 0.6%
minerals: 0.2%

If this is reliable, it would mean that the fermentable content of a typical honey is 77.5%. Based on John Palmer's volumes of CO2 to weight corn sugar, I would use 1.8 oz corn sugar to get the 1.5 volumes CO2 that I want for my special bitter. But because honey is only 77.5% fermentable, I would want 1.8/0.775 = 2.3 oz honey to achieve the same result. But let's say this average result is off by even 25%, you have a range from 1.3 to 2.2 oz corn sugar (which corresponds to ~1.25 to 1.75 volumes of CO2). Therefore, it would be nearly impossible to get bottle bombs considering that only happens at >4.5 volumes CO2.

While honey is reported to be hydroscopic, I don't think that a sealed container could absorb enough water to make much of a difference.