The first American to orbit the earth, John Glenn “carried a menu of freeze-dried powders, tubed spaghetti and roast beef, and a variety of foods reduced to bit-sized cubes The cubes flaked into crumbs that floated around the astronaut’s capsule….”
“The Gemini program began in 1965 and with it came NASA’s revised approach to menu development. Gemini astronauts ate the same bite-sized cubes as Glenn but coated with gelatin which crumbled less. Also carried were freeze dried (rehydratable) foods packaged in special containers to allow better reconstitution. Menus included shrimp cocktail, chicken and vegetables, butterscotch pudding and applesauce. Astronauts selected meal combinations as they pleased.”

from: Subsistence in Space by Nanette Gallant. U.S. Army Quartermaster Professional Bulletin – Summer 1992.