if one train full of sugar leaves chicago at 3pm...

October 19, 2011 10:34 AM

If I combine two parts white granulated sugar and one part water (by volume), how much 2:1 sugar syrup will I end up with? Alternatively, if I boil down a 1:1 sugar syrup (say 16 cups water and 16 cups sugar), at what final reduced volume will I have achieved a 2:1 solution?

Bonus question: Will I have produced an inverted syrup if I boil down a 1:1 solution to end up with a 2:1 solution? Can I BWB process it in sterilized jars and keep it on the shelf with a reasonable expectation of stability?

Thanks, AskMe!

posted by peachfuzz to Food & Drink (8 answers total)

According to this site: 2 parts, by volume, of sugar to 1 part water will yield 2 parts of a 63º Brix solution (1.310 specific gravity)
posted by weapons-grade pandemonium at 10:48 AM on October 19, 2011

I've not sat down and done the math, but I suspect that a heat-alone method will leave a not-insignificant portion of sucrose in the solution. Traditionally cooks add a little acid (lemon juice, cream of tartar, etc.) to get all the sucrose hydrolyzed before you get bored of standing at the stove. If you're going for long-term storage, I'd think you'd want as little sucrose as possible.

Invert sugar solutions will eventually crystallize, but there's no harm in that beyond appearance. The re-application of heat will straighten things out. As to canning the stuff... it's got such a low water content that I suspect very little would like to grow on it. (Think: honey.) I've never actually tried canning straight sugar sol, though. I'd be interested to know how it goes.
posted by introp at 11:02 AM on October 19, 2011

2:1 syrup means two parts sugar, one part water by mass, not volume. In order to make a 2:1 syrup by volume, you need roughly a 5:2 syrup by volume (this depends on the density of your sugar). The density of 2:1 syrup is roughly 1.33, so if you make syrup with 1kg water and 2kg sugar, you will end up with roughly 2.25L of syrup.
posted by ssg at 11:04 AM on October 19, 2011

Response by poster: hmmm, okay. Whoops. Off to dig up a hydrometer!
posted by peachfuzz at 11:10 AM on October 19, 2011 [1 favorite]

Uhh, no, sugar solution ratios (to a chef, at least) are by volume. The absolute maximum of solubility of sucrose in pure water is 82.6% m/m. Your traditional 1:1 sugar solution used in so much baking, if meaning m/m instead of v/v, would be physically impossible without a pressure cooker taking the water up to ~ 150 C or higher.
posted by introp at 11:31 AM on October 19, 2011 [2 favorites]

Response by poster: I was wondering how I could ever dissolve five cups of sugar in two cups of water. Thanks, introp!
posted by peachfuzz at 11:55 AM on October 19, 2011

Uhh, no, sugar solution ratios (to a chef, at least) are by volume.

I guess this means different things to different people.

The absolute maximum of solubility of sucrose in pure water is 82.6% m/m. Your traditional 1:1 sugar solution used in so much baking, if meaning m/m instead of v/v, would be physically impossible without a pressure cooker taking the water up to ~ 150 C or higher.

The solubility of sucrose in water is roughly 2:1 at 20C. I have no idea where 82.6% comes from, but it isn't correct. So 5 cups of sugar will dissolved easily in 2 cups of water with just a little heat.

Anyone who has ever made a sugar syrup can attest that you can easily dissolve sugar 1:1 by mass in water.
posted by ssg at 4:24 PM on October 19, 2011

I suppose my brain failed at recalling my chem classes. :( A little quick googling shows me that the 82.6% number I remember is mass fraction at 100 C, which a little math tells me would be... 4.74 (sugar) : 1 (water), m/m. It seems reasonable that could be 2:1 (or slightly better, even) at 25 C. My apologies.
posted by introp at 9:00 AM on October 20, 2011