How do astronauts eat in space?

Orbital food relies on packaging designed for storage without refrigeration and for weightlessness. The first category covers rehydratable foods and drinks — soups, scrambled eggs, breakfast cereals — to which the crew adds hot or cold water from the galley dispenser. The second gathers thermostabilized meals, heat-processed and ready to eat, which are warmed in the galley oven before serving. The third covers foods in their natural form, ready to eat straight from transparent packaging.

Each resupply spacecraft also brings a limited amount of fresh fruit and vegetables: with no refrigeration available, they must be eaten within the first few days. Crews always welcome them.

The mechanics of a meal change completely. Nothing rests on a table: a strip of velcro under each pouch holds it to the meal tray, and restraint nets keep packaging from floating away. Powdered drinks come in soft pouches to which water is added, then drunk through a straw. Food is eaten with a fork or spoon, from single-use packaging that avoids any dishwashing.

Salt and pepper exist in liquid form, in dropper bottles: salt dissolved in water, pepper suspended in oil. Bread, which did not stay fresh and left crumbs floating around the cabin, is often replaced by tortillas, which produce no crumbs and are used to make sandwiches.

Menus are not imposed: crew members choose their own and, before flight, taste and rate the dishes on offer; dietitians use these ratings to build the menus for each expedition. On the nutrition side, the goal is to provide enough calories, vitamins and minerals to maintain health. Sodium and vitamin D affect bone density: sodium intake is therefore limited, and since the body normally produces vitamin D through sunlight on the skin, supplements are provided.