Astronauts in space live on processed, pre-packaged space rations such as fruits, nuts, chocolate, shrimp cocktails, peanut butter, chicken, and beef to name a few. These have often been sterilized by heating, freeze drying, or irradiation to make them last and key a challenge for the US Space Agency NASA has been to figure out how to grow safe, fresh food onboard.
Click here for original story, Space lettuce: Nutritious and safe crops would be a dietary supplement to assist long-distance space missions
Source: Phys.org