Ever wondered what do astronauts eat? How do they survive ? How their nutrient requirement is fulfilled? Well, there’s no food delivery to space. They survive on highly processed form of food known as ‘Space Food’
Space, where astronauts travel for long time is long miles away from the earth . Space is a region where the gravitational force becomes almost zero and the region is completely devoid of air.The place is far above the four layers constituting atmosphere of earth and there exist complete vacuum. So it is obvious that astronauts do not usually take foods which we consume in our day to day life.Now let us know about the space food broadly.
Let us now step down to the past. All of us know that Neil Armstrong was the first person to keep feet on the moon and the spacecraft which made the mission successful was APOLLO. Since the famous Apollo-era , the use of space food increased enormously. Space foods are processed food which is first prepared and then tested in labs to ensure its safety, storage life, quality, and viability. All foods taken by spacecraft are designed and manufactured on earth. The foods are made such that they can be easily packed and should be able to satisfy the average energy requirement of the space travelers. The food is prepared as per Recommended Dietary Allowance of all the nutrients. The National Research Council has set up formulas to find out the basal energy expenditure (BEE) that is the energy required to accomplish all the metabolic activities of the body.
For women the formula is, BEE = 655 + (9.6 x W) + (1.7 x H) – (4.7 x A)
For men the formula is, BEE = 66 + (13.7 x W) + (5 x H) – (6.8 x A)
( where W = weight in kilograms, H = height in centimeters, and A = age in years)
Production Process Of Astronaut Food | Space Food Production Process
All the foods are developed and designed in Space Food System Laboratory, NASA . All type of food scientists , engineers , dietitians combine their knowledge and give rise to new food product after going through various experiments.They ensure the nutritive value , safety , hygiene and keeping the quality of the food and only after it can be sent with the space shuttle. It also undergoes microgravity test in NASA’s KC-135 airplane most popularly known as “vomit comet” wherein a zero gravity region the behavior of food is observed before is approval. They have developed eight food processing techniques such as re-hydrated , thermostabilized, freeze-dried , irradiated , natural occurring dry foods , fresh agro produce, medium moist food, frozen food. All the space foods are precooked and preprocessed.
We have a common habit of storing food in the freezer in order to increase its shelf life but in space, there is no facility to provide a cold storage to the foods. So now the problem arises is how to keep the food for a long duration of six months and more. The space food research unit of NASA follows a method where they first process the food and keep it in freeze,then they take it out and keep it in the vacuum oven where the moisture is removed from the food and the food becomes dried.There is a remarkable reduction in the size of the food and it becomes easier for packaging.The allowed weight of the food for a single person in one day is 3.8 pounds accompanied with the package weight of 1 pound. The packaging is made in such a way that it can be managed to have it in microgravity region .The foods are of ready to eat type and it may need the addition of some water or heating if needed. If fresh agro based products are taken along with the astronauts then they need to be consumed in earlier days to avoid its spoilage as no refrigeration system is available there.
The food which needs water to be added externally is known as Re-hydrated food and the water in made available by orbiter fuel cells.During the processing of these type of food, water is removed by drying so that water activity can be reduced below the point where no microbes can grow. Foods such as chicken,rice, macaroni,cheese ,scrambled egg comes under this category of food. Milk is provided in dry form along with sugar which only needs water to be added.
There are also thermally treated foods which undergo high temperature treatment so that enzymes can be deactivated and microbial growth is stopped.These are known as Thermostabilized food. Application of heat extends shelf life by years.These are packed in aluminum cans or steel coated cans , plastic packs , retortable pouches having layers of protection. The packs are easy to open and use. Foods such as mushroom,tomato,eggplant etc.
The foods can be made self stable by exposing it to ionizing radiation known as Irradiated foods.
Beef steaks come under this category. These are first cooked then packed and then exposed to ionizing radiation in order to extend its shelf life. If we are more concerned about extending the shelf life of the food commodities then we should focus on water activity and pH which are the major determinants in deciding whether bacteria or molds will grow. There are various drying methods available to remove water such as freeze drying method , vacuum oven method.Dry fruits such as nuts like cashew ,almond etc. don’t need further processing and can be packed in plastic pouches which can be taken easily and can be easily consumed.
MENU SELECTION FOR SPACE FOOD
Food choice is made by astronauts and it is granted after seeing its applicability and availability during their flight.It is done 8-9 months prior to the launching of spacecraft. The packaging is done individually that is for each person separately.
A series of steps are prescribed before for the astronauts how to use foods.Those are as follows,
- Collect meal tray and utensils
- Display preselected meal on the computer
- Locate food using location display function
- Prepare food items for heating
- Place items to be heated in oven
- Enter cook control codes and press “start”
- Rehydrate beverages
- Place beverages on meal tray
- Retrieve refrigerated foods
- Place refrigerated food in meal tray
- Retrieve items from oven
- Place heated foods in meal tray
- Place used containers in trash compactor
- Clean and stow meal tray and utensils
SOURCE : NASA
SOME FACTS ABOUT SPACE FOOD
- Apple sauce is the first food to be used by astronauts.
- Astronauts use tortillas more preferably than bread because it prevents floating.
- Salt , peppers are used in diluted form .
- The flavor of food becomes bland that is tasteless. So they use hot sauce a lot to regain the taste.
- They eat foods directly from cans.
- The weight of freeze dried food is quite less.
- Diversity in culture is also seen in space foods.
- Foods can be masticated and can be swallowed in zero gravity.
- 203 types of food are there in the menu.
- No cookies and bread are allowed to space.
- All the instructions are printed in English and Russian on the pack.
- They take vitamin D additive with them.
Now we have some idea about space food and how they are being prepared. Nowadays there are various research and development which lead to the development of more delicious and nutritious food for the space travelers.Scientists are focusing more and more on keeping quality and improved preservation techniques for the products so that they can be stored for a prolonged period.