Reader Jenni asks whether a candy syrup is usable for anything else after it’s overcooked, i.e., once soft ball syrup is cooked to, say, firm ball syrup. The answer, Jenni, is that you can fix an overcooked candy syrup by simply adding more water to it. For there’s really no “cooking” going on in a candy syrup that contains only sugar and water. Proteins aren’t coagulating, starches aren’t gelling, fats aren’t breaking down, nothing like that is going on. Indeed when you boil a sugar syrup, as long as it’s below the caramelization temperature, only one thing happens: its water content goes down. Seen in that light a sugar syrup’s temperature isn’t so much a measure of how hot it is — though it certainly is that — it’s a measure of water content. Soft ball syrup is soft because its relatively high water content makes it pliable. Hard crack is hard and brittle because it has a good deal less water and is so very rigid.
Add a few drops of water to a boiling sugar syrup and its temperature will drop instantly, not because the water is spreading coolness around, but because the water content of the syrup has just increased. Pretty cool huh? So if you overshoot the mark on your candy syrup don’t fret, just carefully add a little water and keep cooking. As long as it isn’t caramel yet, you can easily save it. Thanks for the question, Jenni!