We had an excellent four day mini-course in sugar work at school last block, so we learned how to cast, pull, and blow sugar. For all of these uses, we all made a basic sugar stock out of 10# granulated sugar, 5# water, and 2# glucose (which inhibits the formation of crystals). It was skimmed, brought to a boil, and then cooled until it was needed for use.
For casting sugar — that is, pouring it into a mold that gives it shape — only powdered coloring needs to be added before bringing the sugar stock to 320F and then pouring it into greased molds on silpats or aluminum foil. We stored these on baking sheets with little canisters of limestone inside to keep moisture away from the sugar. Even so, sugar pieces generally last 3-4 days, or longer if isomalt is used or you have a humidity-controlled chamber.
For pulling sugar, we want it to be more elastic, so before it is brought to 320F, tartaric acid is added, as well as coloring. The acid gives the sugar pliability, but if too much is added, it will infinitely pliable and won’t set up. For 5#, we used 14 drops acid. Before it cools, it needs to be pulled (literally, the whole thing, pulled and twisted and folded, again and again) for a while so that air is incorporated and it will be shiny and opaque. It is then cut, cooled, and ready for use once it is heated again.
Our station for pulled and blown sugar work involved a plexi-glass foldable box with an open side and a spot for a heat lamp on top. This kept the sugar warm and melted it, though we also used the microwave for faster results. Sugar cools down and gets hard relatively fast, so you always have to be aware of its temperature and usability. Pulled sugar can be used to make flower petals (and ribbons, etc), and you take a hunk in your hand (wearing latex gloves), and spread apart one side with two hands so that the edge is thin. Then you pinch and pull, pause to let the sugar set a little and then snap it off and onto a silpat to set. When you want to put all the pieces together, you can wave an end of a piece over an alcohol burner so that it melts a little and will adhere to each other.
For blowing sugar, you also want a flexible sugar, so we used about 18 drops acid for 8# stock and brought it up to 320 until we cooled it in silicone molds. We then reheated it the next day so that it can be manipulated. We used a hand pump with a wooden spout attachment, and simply encased the end in a piece of sugar before carefully pumping air into it and supporting it with one hand. The trick here is get the whole shape even and with uniform walls without it deflating or shattering (if it cools too much while you are still pumping in air — it’s just like shattered glass). You can make spheres, or other shapes depending on how you pull it and if you can make it set without collapsing. Using an air dryer meant for pets with a fan setting helps to cool and set the sugar. We initially blew sugar that had not been pulled because that kind is opaque; instead, our sugar was clear, so we could see how the air was shaping up within the chamber of sugar.
It was a lot of fun working with sugar, and I regret that I was sick on the last day when we made sugar showpieces; I even had a candy motif all planned out. You work with the sugar when it’s very hot, but you just work fast and it cools pretty fast anyway, so it’s not frightfully hot, and you also put it down as often as possible. Blowing sugar and casting sugar require minimal contact anyway. The red light of the heat lamp can be a little headache-inducing, so it’s important to look away as much as you can. Your ability to create shapes that you want is only limited by your imagination with how to work with sugar. I liked bubble sugar, for which the sugar was poured over a parchment paper brushed with alcohol, and the end result is a bubbly look, almost like a sheet of sea spray.
I didn’t have the time to quite perfect my technique, but check out Ewald Notter for true sugar genius.