The Reason Why Astronauts Can't Have Good Pizza In Space
The International Space Station (ISS) orbits at an average altitude of some 250 miles above the Earth, so it's not like astronauts can call a pizza delivery man. Oh sure, in 2001 Pizza Hut sent some six inch cheese and salami pies to the ISS, but it was a monumental task, and it took much longer than 30 minutes to arrive.
Moreover, there are a number of things astronauts can't consume while confined inside what amounts to a hamster habitat streaking through space at 17,500 miles per hour. Alcohol, ice cream and anything that's crumbly — like bread — are all on the no go list. So it's safe to assume that pizza dough would fall into that "bread" category as well, right?
A crispy crust is a must, but the weightlessness of space combined with the safety hazard that comes with crumbs drifting around and getting into eyes, air vents, or expensive electronic equipment must be considered when putting together a pizza. Vickie Kloeris, former ISS food systems manager at NASA Johnson Space Center, says the crust is "always soggy or chewy" and "doesn't meet anyone's expectations."
Back in 2013 NASA gave a first round of funding to an Austin, Texas, small business to develop a 3D food printer. Systems and Materials Research Corporation (SMRC) wanted to build a machine that could make food from scratch, on demand. If it sounds like a Star Trek replicator, it's not that far off.
Pizza night on the Space Station
The SMRC device could make food by mixing powdered macronutrients (i.e., protein and starch) with oil or water in the printhead. It would be combined with micronutrients, flavors, and smells and then get sprayed out just like an inkjet printer. One of its first recipes was printing pizzas in layers, starting with the dough, then the sauce, and finally the toppings. NASA never provided a second round of funding.
Being on a restrictive diet for weeks or months on end tends to change one's perspective on what constitutes "good" and "bad" food. In 2017 NASA sent the Expedition 53 crew a bounty of pizza fixings, including pre-made Boboli dough. The space jockeys ditched their space suits and donned space aprons to actually make and eat space pizza on the ISS; though it probably wasn't voted "best of" anything.
The recipe for space pizza is limited to pastes and sauces that can be spread onto uncooked, pre-made dough, and the toppings must be able to stick to whatever sauces have been applied. Additionally, a whole lot of teamwork is needed to keep everything anchored down (using strips of tape) during all the prep work. While the pies can be warmed up, a truly crispy crust isn't possible because conventional baking ovens aren't a standard feature on the ISS... yet. Until they are, they'll have to be content with a passable facsimile that will satisfy the craving for a little slice of home.