On the International Space Station at the moment, astronauts can choose between about 200 different meal options. But on smaller spacecrafts, where cargo weight and storage space are more tightly controlled to ensure enough room for fuel, the US space agency is looking for ways to maximize efficiencies.

Earthlings use food bars to replace meals on occasion—not always successfully— but there are no reliable products for the long-term, wholesale replacement of meals. “There’s no commercially-available bar right now that meets our needs, so we’ve had to go design something that will work for the crew, while trying to achieve a multi-year shelf-life,” NASA said in a statement.

It’s not just food bars with which the space agency has been experimenting. Engineers are also looking to optimize in-flight management of fresh vegetables, too.

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