The Great Yeast Experiment

Last week we took a field trip to a local bakery, in order to get free samples learn about the science behind baking bread. And boy did we! We bake bread a lot around here, and the kids already loved watching the yeast bubble up, but now they understand just what yeast does -- which is burp, of course. They used to be able to tell me that the yeast is alive and that it eats the sugar when the water is heated to the right temperature, but now they just say, "It burps."

Besides that important tidbit, they also learned the process of growing wheat and why we can't grow it down south (because it will never dry out in our humid air), and just how the wheat in the fields is turned into flour. As the baker explained the milling process V-Man piped up and called out, "Just like at the mill we saw!" And indeed, the weekend before we had visited an old mill and the kids had played around on the millstones. If education is about making connections, then my boy had done just that.

They came home with wheat to plant, which we did, and the very next day it had sprouted. That stuff grows fast! And every morning there are water droplets on the tip of the blades. I'd love to know why.

We re-enacted one of the yeast experiments to prove that yeast expels carbon dioxide as it eats the sugar, which is what causes bread to rise. You need a packet of yeast (or about 2.25 teaspoons), an empty water bottle, a stretched-out balloon, and two tbsp of sugar. Heat one cup of water to 110 degrees, pour it into the bottle, add the yeast and sugar, slip the balloon over the top, and watch it inflate.