All that Grows (in Maple Syrup) Is Not Mold
by Tig Tillinghast
We tend to make our maple syrup overstrength, ranging from 70 percent solids to 72 percent solids, about two to four percent higher than Vermont recommends. We just like it that way, even though some sugar comes out of solution in the form of crystals over time. When consumed before that happens, though, the extra syrup thickness packs quite a maple punch.
Here is a picture of a maple syrup bottle consumed slowly over a year, leaving a residue of maple sugar crystals…

Interestingly, we’ve been polling people over the 2008 to see whether they prefer thicker, “normal” or thinner maple syrup. The vast majority of people said they preferred the standard thickness. One or two said thinner, and perhaps a quarter said thicker. This surprised me, as I assumed everyone would prefer thicker maple syrup over the norm.
When asked both if they knew their preferences well and whether they liked lighter or darker maple syrup, the folks who indicated they knew their preferences mostly said darker maple syrup, perhaps by a 2-1 ratio. The people who indicated that they weren’t confident in their preferences were more apt – but not by much – to say lighter maple syrup. This is consistent with studies done by maple research centers, although I have not seen them couch their questions with the information about how confident the respondents are in their various answers.
A before and after shot of the bottles of overstrength maple syrup.

The maple syrup bottles above are a recent gift to some in-laws, next to the bottle just recently finished off from last year’s gift. Some customers see the maple sugar crystals growing in glass containers and assume that it must be some sort of organic growth. I find that they express this concern particularly when maple sugar just starts to come out of solution, as the early crystals look an awful lot like a fuzz on the inside bottle surface, and sometimes floating just under the maple syrup’s surface.
I am not sure about this, but I suspect that overstrength maple syrup is less friendly to growths because of its lower than normal water ratio. Typically, growths in maple syrup happen only in the thin layer of water at the top of the bottle, often resulting from condensation.
Comments
I have often reheated maple syrup once it has crystallized. This melts the sugar crystals and turns it back to syrup. You don’t even have to take it out of the glass bottle. Just heat some water and dip the glass in. Just a word of caution don’t heat the glass to quickly or it could crack.
What do you think of heating maple syrup like this? Does this effect the flavor of the syrup?
Great idea. One of my customers actually broke open a glass bottle to get at the rock candy formed at the bottom. Which was probably pretty indistinguishable from the broken glass shards. Would make for a pretty funny warning label, though: “Don’t crush this bottle and eat it by mistaking the glass for sugar.” Worth considering.
I really doubt heating maple in the way you suggest would hurt the flavor at all. Unlikely to even affect color very much. A great idea, especially as syrup that takes up crystals while hot remains overstrength and thick (the way I like it) until the sugar again comes out of solution given time and colder temperatures. I’d venture to guess it would work just as well with plastic jugs, although the opaque walls of those jugs don’t let people know that there is sugar there to be dissolved.
Can’t wait to try it myself. -tig