Excerpt:
Eating in space for John Glenn turned out to be an easy though not too tasty experience. Before the flight, some experts were worried that, in weightlessness food would be hard to swallow and as a result, collect in the throat. Glenn found that eating in space was relatively easy and once the food reached the mouth, there was no problem in swallowing. Other Mercury astronauts following John Glenn were forced to endure bite-sized cubes, freeze dried foods, and semi-liquids in aluminum toothpaste-type tubes. They found the food unappetizing, had trouble rehydrating the freeze-dried foods, and disliked squeezing the tubes. Futhermore, crumbs from the bite-sized cubes had to be captured to prevent them from fouling instruments.