F&N in outer space - EFR 5-41

Food science is not only challenged with meeting the needs of those on the Earth's surface, but those who travel out from the planet. This article describes some of the special needs when considering "space menus."

(Submitted by Mary Cheatham, Extension graduate assistant)

Thirty years ago, astronauts pumped applesauce from a toothpaste- like tube, popped gelatin-coated cubes, mixed freeze-dried powders and squeezed various semi-liquid foods from aluminum tubes for dinner.

Today astronauts enjoy many of the same foods in the same form as earth-bound diners. Through the work of NASA food scientists and nutritionists, today's space shuttle astronauts eat scrambled eggs, yogurt, chicken cacciatore, spaghetti, fresh bread and brownies. Some of these foods must be prepared using special processing techniques. No refrigerator or freezer is on board the Space Shuttle, yet even higher standards of food safety must be met through uses of other technologies such as irradiation, intermediate-moisture foods, thermostabilized foods and rehydratable foods.

"Intermediate-moisture" is a method of preserving dried fruits and beef by restricting the amount of water available for microbial growth, but retaining enough moisture to give the food a soft texture. These foods are ready to eat without having to rehydrate.

Puddings, fruits, tuna, salmon, and other foods that would be eaten out of cans, or from the flexible retort pouches are heat processed to destroy harmful microorganisms and enzymes. Irradiation of frozen, packaged meats for NASA programs has been approved by FDA.

All foods chosen for space missions are thoroughly analyzed by the staff at the Food Systems Engineering Facility at the Johnson Space Center in Houston. Foods are added to the menu only after they have undergone all the necessary research and development and are approved for flight.

Nutrition is critical. "In space, your body is under a lot of stress", according to Charles Bourland, Ph.D., subsystem manager for space station food at NASA. Astronauts can have problems with motion sickness, dehydration and weight loss during the first few days of a mission. Diets are designed to supply each shuttle crew member with the Recommended Dietary Allowances (RDA) of vitamins and minerals necessary to perform tasks in the environment of space.

Astronauts going on a mission select their menus from a standard food list. The foods are then prepared and packaged for the mission. Astronauts are allowed to take along some of their favorites in a fresh food locker. However, foods that crumble easily, such as one favorite - pecan shortbread cookies, are not allowed.

The effects and risks involved in space flight include changes in body composition. Motion sickness occurs in a substantial percentage of astronauts. This usually lasts from 3 to several days. Food and fluid intake are decreased. Water losses from the body occur partly from this initial decreased intake and also from headward shifts of fluid in weightlessness and subsequent loss.

Weight loss occurs, partially due to this water loss, but also due to fat and protein loss. The protein loss occurs partly due to atrophy of postural muscles in zero gravity. If fat loss occurs it is due to a calorie deficit (output greater than intake).

Calcium loss from bones in weightlessness is a complex process. The Soviets have proven that with several measures, weightlessness up to 1 year can be tolerated without fractures from bone loss.

Sources:

Space Food Takes A Giant Step March/April 1995 issue of Food Insight

Paul A. Lachance, Nutrition in Space in Modern Nutrition in Health and Disease, edited by M. Shils, J. Olson and M. Shike, published by Lea and Febiger