A German start-up has prototyped a bread oven that operated in microgravity that may someday enable astronauts to enjoy fresh-baked goods in space. Currently, astronauts eat tortillas because they aren't crumbly and have a long shelf-life. (See the below photo of a rather unappetizing tortilla cheeseburger on the International Space Station.) From Space.com:
On Earth, bread needs to be baked at a temperature of about 400 degrees F (200 degrees C). Once it’s done, the bakers remove it from the heated oven. But that would not be possible in space. Processes such as thermal convection, which helps to mix up air on Earth, don't work in space. If a bubble of air that hot were to escape from the oven in orbit, it could stay floating inside the station for quite a while, posing a serious health risk to the astronauts, (Bake In Space CEO Sebastian) Marcu said.
Marcu said the team has found a way to overcome this challenge.
"We basically put the baking product, the dough, inside the cold oven and start heating it up," he said. "Once it's almost done, we start cooling it down. But at that time, any product will start to get dry, and that's why we need to design the oven so that some water is added during the baking process."
The oven also needs to be able to operate with only 270 watts of power — about one-tenth the power used by conventional ovens on Earth. Marcu said the team hopes to have a prototype ready by the end of this year.
Mastering the process of baking is only one step toward making the space-grade bread. Crumbs could damage the station's equipment, or astronauts could accidently inhale them. Marcu said he hopes the combination of the new baking process and a carefully designed dough will solve the problem.