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Biography
NASA Career
FACTORS AFFECTING FOOD DEVELOPMENT FOR SPACE FLIGHT
by
Astronaut John W. Young
NASA Manned Spacecraft Center
Houston, Texas
Conference on Food Science at -
U.S. Army Natick Laboratories, Natick, Massachusetts
November 20, 1963
It is a pleasure to be here today to discuss
some of our food development problems for space flight.
As you probably realize, one of the primary objectives
of space flight test work is to prove to our satisfaction that a man can
live and work effectively in space. Even in these relatively early stages
of the space program, we are planning for the time when we will operate
on a routine basis on long duration flights in space. In this presentation,
reference to space means weightlessness or zero-g effects encountered in
orbital missions.
As we begin the two-man spacecraft project called Gemini,
we will experience long duration routine space flight for the first time.
It will be our first chance to show that men can eat, sleep and work in
space on a day-to-day basis. The groundwork for the Gemini program was
established by experiments and tests made in the Mercury program. At NASA
we continually remind ourselves of the lessons learned from the Mercury
Project to establish a solid basis for future programs. I will review several
food problems in Mercury that have directed our thinking and established
requirements for both the Gemini and Apollo programs (Apollo is the three
man spacecraft with the lunar mission).
Mercury astronauts faced, as you recall, many unknowns
in their first flights. It seems weird to say so now, but some people had
doubts that survival was possible under the zero-g conditions of space
flight. The mere experiment of eating under weightlessness caused some
concern. It was one of the physiological unknowns of space flight.
Before we had acheived orbital flight we had experienced
weightlessness by flying high-speed aircraft over prescribed Keplerian
or ballistic trajectories. During these trajectories for approximately
45 seconds the forces of gravity are balanced out and weightless experiments
can be performed. This training gives us a feel for some of the problems
in weightlessness, but valid conclusions on the long duration effects of
weightlessness cannot be drawn from it.
So, prior to Mercury flights, we, from weightless experiments,
knew that liouids would not flow freely nor would loosely packed food stay
together. We knew that food and drink would have to be packaged and that
it would have to be transferred to the mouth from the container by force.
The simplest way to do this operation was the use of malted milk tablets.
Squeeze tubes like toothpaste tubes were also used. John Glenn carried
food in these squeeze tube containers in the puree or baby food form. This
first experiment with eating in space seemed to indicate that there would
be no problems. Glenn suggested in his flight report that carrying normal
foods would be possible as long as they did not crumble. On Scott Carpenter's
flight, man encountered the first warning of a potential problem in space
food. Crumbled food floats freely causing a nuisance and a danger if it
should drift into vital equipment. Combined with free moisture, crumbs
could cause electrical shorts on electronics equipment with possible catastrophic
effects unless proper precautions were taken.
Xylose absorption tests indicated that carbohydrate food
was being digested on both Carpenter's and Glenn's flights.
During Schirra's flight, food tubes were also used. Although
he did not experience any real hunger he consumed a tube of peaches and
one of beef and vegetables. Therefore, Mercury experiments showed that
as long as man can get the food into his mouth, he can eat normally.
With an eye to future flights we wanted to experiment
with freeze dehydrated food. As you know freeze drying removes more than
95% of the water in foods. This food re-hydrated provided a more solid
type diet and added variety to the space flight menu. I hasten to add here
that variety is not the reason for going to freeze dried food. If we used
the bite-size and tube filled foods of Mercury it would require an approximate
weight of 3. 6 lb. /man/day (and 300 cubic inches stowage space) to provide
2500 cal. /man/day diet. The same diet using freeze dried foods, we hope
to result in a food weight of 1. 3 lb. /man/day and a stowage volume of
100 cu. in. /man/ day. Roughly speaking, on a two week Apollo lunar mission
we will save nearly 100 lbs. of weight and 8, 400 cu. in. of stowage space
with freeze dried food. To put it bluntly, we don't have 8, 400 extra cu.
in. of stowage space inside the Apollo spacecraft. Since it will take roughly
800 to 1000 lbs. of fuel and boosters to carry one pound of anything to
the moon and back, weight saving in the food area is vital.
Cooper reported on his flight in the first evaluation
in space of freeze dried food, that difficulties with food containers and
water nozzles during his flight prevented him from properly reconstituting
the food. Due to these problems he only consumed one-third package of beef
pot roast during a 34-hour flight. To correct these difficulties in Gemini
and Apollo, the dehydrated food will be packaged in specially devised "zero-g"
containers. Water for food re-constitution which incidentally is produced
by the fuel cells - combining hydrogen and oxygen to make electricity with
water as a by-product (vital though it is), will be delivered to the spacecraft
cockpit through specially designed probe nozzles. Food will be re-hydrated
by inserting the special probe into a sealed valve and applying the proper
amount of water. Probe removal will seal a check valve to prevent leakage.
The hydration process is accomplished by squeezing the package from 3 to
5 minutes. A feeding seal in the food container neck is broken and the
food container neck inserted into the mouth and the food package is squeezed
to force food into the mouth. The feeding seal is resecured leakproof-wise
by clamping it shut. A germicide in tablet form will be squeezed in the
food package prior to its stowage in the waste container to prevent putrefaction.
This package is designed to insure satisfactory re-hydration and prevent
leakage. All package openings are designed for ready operation and ease
of handling. To supplement the dehydrated food, snack bites packaged in
edible coatings can be eaten, wrapper intact, to prevent crumbling. Cooper's
main food consumption was these bite-sized cube foods and bite-sized sandwiches.
Gordon stated that he was not particularly hungry and ate mainly because
it was on the schedule. At only one time during the flight, which you recall
was 34 hours, did Cooper experience hunger which he satisfied by eating.
The main conclusion which can be gained from a review
of the Mercury flights is that eating is not the vital part of a space
flight mission. We will eat to maintain performance levels for long mission
durations.
You are probably all familiar with the National Academy
of Sciences working group report on nutrition and feed problems. It recommends
that hi-energy balanced formula diets can be tolerated for periods of up
to three weeks in space flight. So a great variety of food may not be necessary.
In fact, we are presently planning to repeat the Gemini menu every fourth
day. But simple foods must be readily accessible and easily handled in
orbital conditions. The National Academy of Science report concludes that
a formula diet could provide this result as well as provide a low residue
diet. In our survival training exercises we have been frequently told quote,
eat anything that doesn't eat you first, unquote. But this is perhaps a
good attitude to adapt in regard to a flight diet. Weight restrictions,
as I mentioned, will require us to have a necessarily frugal diet, but
not necessarily monotonous. I have eaten several proposed freeze dried
meals and find them very palatable. In my opinion, the astronaut diet in
terms of palatability and variety will fall between the survival ration
and the typical noon banquet menu.
In space we determine when to eat by the workload or the
mission plan. If, for example, we want to do a rendezvous with another
spacecraft during an earthly dinner time we eat later and we are planning
four meals a day in Gemini for the pilots with "night"watches. So we don't
feel that when we eat will be a problem.
In summary, there is a diversity of food products being
developed for space flight under contract to the National Aeronautics and
Space Administration by several industries. It has become a challenge to
the industries to keep these products simple, palatable and easy to use
in a zero-g environment. Astronauts are not passengers on luxury liners
who have to be fed delicacies during the flight. Our major item of concern
is the packaging and handling of the f ood. The food must be properly contained
to prevent leakage and crumbling. Excessive time and effort to process
the food, we have discovered, discourages food intake during the slack
periods when the astronaut should be eating. The several industries are
now fulfilling our requirements for a light, compact hi-energy well balanced
diet. They are also solving the admittedly difficult problems of package
design for ease of leak-free handling in zero-g. With this type food, we
have every confidence that we will successfully perform on long duration
missions. It is even possible, in fact, that some of us may gain weight.
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