One thing about the World Wide Web is that people rarely use it to discuss their own failures. If you Google "candy recipe failure" you will receive only one posting related to how a candy recipe doesn't work, and that one is mine. Nevertheless, with a little searching, I was able to find an excellent review on the variables and tricks in candy making on the website Baking911. The display on the site is a little busy for my taste, but it has excellent information. There is a more concise explanation (in fact I am sure one site lifted their facts from the other!) at Exploratorium.
Humidity, a fact of life on Fire Island, is the likely reason that my candy recrystallized on me. Since it would be difficult to wait for a dryer day, I looked to see what steps I could use to get me a decent batch of brittle.
Interfering agents are things that stop crystallization from occuring. Combining two sugars helps prevent crystallization because the sugars can't lock together as well. "Inverting" table sugar by adding acid, such as cream of tartar or lemon juice helps break down sucrose to glucose and fructose. For soft candies, such as caramel, cooked at lower temperatures, fatty things such as milk or butter also help reduce crystallization. My prior experience tells me this will not work for hard candies, as the milk or butter solids burn at higher temperatures.
I remade the batch, modifying my original recipe as follows:
HUMID BRITTLE RECIPE!
- 4 cups sugar
- 1 cup corn syrup
- half of a squeezed lemon
- 1/2 cup water
This solution boiled to 325 degrees without a problem. I then added lightly salted peanuts and the brittle was formed. My one note is that using a combination of sugars did seem to give a minimally more chewy result, although this may just be my imagination