During the initial phase of the Manned Orbiting Laboratory (MOL) program, existing space feeding systems were evaluated for possible use. The time frame of this evaluation was 1965 to 1967, at which time the Gemini flight program was yet to be completed and the Apollo program was in its development phases. There was no qualified 30-day feeding system for space application. With the assistance of the U. S. Army Natick Laboratories, the USAF School of Aerospace Medicine (SAM), and the NASA Manned Spacecraft Center (MSC), an in-depth review was held .
It was determined that the Gemini/Apollo feeding system would initially be considered for use on the MOL. It was felt that the greatest advantage could be derived by both MOL and NASA by concentrating efforts on improving the componentry of the already developed Gemini feeding system. Through development and expansion of that technology for use on MOL, most of which would occur during the Apollo flight time frame, mutual benefit could be obtained. The NASA development efforts in refining the Gemini feeding system for use in Apollo and our efforts in further expanding these concepts could be interwoven so as to benefit both agencies.
Although the history of feeding systems will not be detailed in this paper, it should be remembered that spaceflight systems were developed along lines stressing a normal progression of increasing complexity of accomplishment from Mercury to Gemini to Apollo. The unknowns were great; planning was accomplished in increments; 30-day flights in the days of Mercury, when space night was measured in minutes to hours, were but a dream. Nevertheless, an attempt was constantly made to develop the feeding system as an integral part of the total space system. It was necessary to conceive of it in terms of the mission, systems capabilities, crew requirements, etc. lt is to the great credit of NASA and all the agencies and contractors that have supported the efforts to date that the feeding systems development incorporated rational systems engineering. The application of dehydrated foods, the development of zero-G feeders and packaging materials, the delineation of nutritional requirements, etc. were no small effort.
The 14-day Gemini 7 flight was up to that date the most significant test in space of spacecraft systems, crew performance capabilities, and environmental control and life-support systems, one of which was the feeding system. As has been detailed elsewhere, the Gemini feeding system was configured to meet certain requirements; heat, vibration, and  bacteriological criteria, nutritional levels, procedural use requirements, use in the confined compartment of the Gemini spacecraft, and utilization of fuel-cell water at its spacecraft temperature of 80° F were but a few of the environmental criteria.
In August 1967, after industry proposal evaluation, Whirlpool Corp. was selected to develop and produce the MOL Feeding System Assembly. This feeding system was to be composed of food substances prepared in the form of dehydrated bites which were to be eaten in the desiccated state and to be rehydrated during the process and various dehydrated foods and beverages which were to be rehydrated prior to eating and drinking. There were approximately 40 items available at that time. The U. S. Army Natick Laboratories supplied "Space Food Prototype Production Guides" for Whirlpool Corp. to incorporate into production specifications. Hot water to 155° F and cold water to 40° F was to be available for the rehydration. Twenty-six hundred car/man/day was felt at that time to be the caloric requirement. Microbiological standards, as developed by the U. S. Army Natick Laboratories, were applied. Maximum organoleptic acceptability was to be sought.
The food was to be packaged in the Gemini developed zero-G feeders with a mouth spout and hydration valve arrangement. The feeders would be scissor-opened and the food and liquids squeezed into the mouth. The bite packages would be scissor-opened and the bites individually removed for eating. Rehydratables and beverages were in 5-oz-capacity bags. Bite-food bags varied in size. Food volume and weight were limited to 195 cu in. and 1.7 lb/man/day. .An antimicrobial agent was attached to each rehydratable food package.
Procedural requirements detailed a desire to minimize preparation, feeding, and waste disposal times. In order to make efficient use of the items available, a 4-day menu cycle of three small meals of 10 minutes each and one large meal of 45 minutes was desired. Mineral content was based on the recommendations of the National Research Council. The caloric distribution was to be 27 to 34 percent fat, 10 to 15 percent protein, and 50 to 58 percent carbohydrate.
It was felt that, in order to utilize the technical capabilities of SAM, the U. S. Army Natick Laboratories, and NASA MSC most properly, the MOL Systems Office should set up a quarterly conference to be attended by all these agencies. This would handle appropriate technical inputs and these quarterly food planning conferences were held from 1967 to 1969. Their format has recently been slightly changed so that the MOL Systems Office and NASA MSC are cochairmen for the Government Agency Food Technology Working Group which held its last meeting at Natick, Mass., in March 1969. This close working relationship has been singularly effective in integrating government-agency efforts toward the present and future requirements of the users, MOL and NASA.
During the development phase of the Whirlpool contract the objectives have been validating this system, developing production specifications, and improving and enlarging the variety of foods. Dr. Vanderveen, in a preceding paper entitled "Evaluation of Space Feeding Systems, " has detailed the validation of the feeding system by adding information about the reliability of the zero-G feeders delineating the metabolic characteristics of the food, adding to the battery of acceptance data for both initially considered food items and newly developed items, and improving rehydration information. Major Flentge, in a paper entitled "Quantifying and Improving Manned Orbiting Laboratory Food,"  has detailed efforts in developing production specifications and discussed the enlargement of the food-item list. In particular, more high-nutrient soups and puddings have been added, and the quality and type of bites have been significantly enlarged and improved.
By August 1968 it was felt that MOL had an acceptable feeding system which could be used for 30-day flights, but certain problem areas remained, or at least became more obvious. Since MOL was still in its development phases, an attempt was made to detail these problem areas and, in the time remaining, to solve them. Additionally, these problems would be common to the upcoming Apollo flights, and solutions for some of the more readily solvable problem areas could certainly be of benefit to Apollo. Also, valid flight information would be gathered during the Apollo flights and would be beneficial in bringing to light any new problem areas.
It was recognized that more natural foods should be developed -rehydratable meat chunks, more vegetables, and high-nutrient cold liquids, to name a few. The compressed bites should be normalized in size so that a bite would be normal to the mouth in both shape and consistency. Also foods should be utilized in a more usual manner, as dessert items, croutons to be used with soups, etc., and not be viewed as the main caloric constituent of any one meal. Food-storage times should be more completely determined and improved so as to give maximum selectability where flights occur over extended periods of time.
In the area of packaging, it was clear that the delivery system must be improved. The complexity and unnaturalness associated with the handling of multiple small packages and squeezing the rehydratables and liquids individually was both cumbersome and time consuming. The advantage of hot and cold water was not completely realized since preparation and rehydration times were long and the thermal conditioning of the food was certainly degraded because of the time required from preparation to actual eating. The multiplicity of packages presented a problem in formulating a normal menu plan. More realistic use of the antimicrobial agent was needed since significant weight was involved in incorporating a pill in each package, and time was involved in removing it, placing it in the package, crushing it, etc. Drinking methods were unnatural; liquids were squeezed into the mouth by rolling up the package like a toothpaste tube. The crew no longer was cramped into a small cabin, as in Gemini, and could now afford the freedom of intravehicular movement. For the first time a feeding station would be utilized and, in general, living would be more normal. The package-to-food ratio was prohibitive and, therefore, not only costly to booster capability but severely limited the important flexibility of meal planning. As an example, 2900 Kcal of food would require the full 195 cu in. of space and 1.7 lb alloted and would contain only 88 cu in. of actual food. Because of the energy requirements and the size of our crewmen it was recognized that as much as 3200 Kcal/man/day might be required. If two large crewmen flew at the same time they could not have the required amount of food. Certainly, food requirements should never be a criterion used for astronaut selection.
Also, of course, crew procedural requirements specified reduction in time and procedures and the development of more flexible meal grouping to offer maximum flexibility to the flight timeline people. Additionally, waste handling most certainly needed to be simplified.
 With these areas delineated and with the growing confidence that was acquired during the Gemini program as to food delivery methods, a prototype package system was developed by Whirlpool Corp. This package would allow spoon feeding. With larger spacecraft volumes available and more known about the handling of foods in zero gravity, this old technology of eating with a spoon, which had been, naturally, considered by many groups previously both within industry and NASA, could become a reality. This concept was evaluated by MOL in a zero-G flight test run at Wright-Patterson Air Force Base in August 1968.
The test revealed that the method was indeed feasible. Food substances adhere well to the package, spoon, etc. Eating is simple and rapid. Simpler flexible hydration valves were evaluated and proved feasible. The entire eating process proved to be a more natural one; food packages could be lined up on the console and food spooned from each package with ease. The package remained open and food residue could be wiped off the spoon in the scooping process on the opening band. Foods could be mixed as when eating at the table. The food itself could be seen and the quantities desired placed in the mouth. This concept was immediately and successfully incorporated in the wetpack Christmas dinner eaten on Apollo 8 and more completely incorporated on Apollo 9.
I would like to point out the great value that direct participation by our crewmen has been throughout the MOL Food System Development Program. As an example of this, in January 1969, four crewmen were fed a complete menu cycle for a period of 4 days. They devoted themselves to the task of constructive evaluation of the food and commented on each food as it was eaten, as an individual item, as part of the meal itself, as part of the day's menu, and, finally, as part of the complete menu cycle itself. Their comments have been directly incorporated into the food design. As a part of the test, daily complete dental examinations were carried out by Drs. Hall and Brown of SAM, who were able to gather important information which has helped us to determine compressed bite size and texture more rationally. The crewmembers learned the importance of diet understanding in selecting foods. In order to have at least two crewmen evaluate each item at least once, a caloric intake of from 2800 to 3400 car/day was required. The crewmen remained active and exercised daily. Their daily energy requirements, however, were judged to be close to those anticipated in orbit. It is of interest to note that all either retained their starting weights or gained weight. All the weight gains could be attributed to too high a caloric intake based on our estimates of 42 Kcal/Kg LBM/man/day.
With the concept of spoon feeding proven to be feasible, the next rational step was taken. A complete systems engineering analysis was undertaken by Whirlpool so as to redesign the MOL feeding system to incorporate this concept and its many possible ramifications, the details of which are discussed by Dr. Roth in his paper "Systems Analysis of Manned Orbiting Laboratory Feeding System. "
I would, however, like to state some of the objectives of redefining the food delivery system and its overall impact on the total feeding system. It must be constantly kept in mind that in cases where system design time is available, maximum benefit can be derived from incorporating new concepts into existing systems if an integrated review of requirements and objectives is  undertaken. Therefore, Whirlpool Corp. was directed to do a complete tradeoff analysis as part of this study. This required detailed objectives and requirements delineation and prioritization. Food storage dimensions became a prime factor and nutrient modularization and dimensional modularization became a necessity. Normal eating and drinking methods, rational combinations of foods, minimization of time, more appropriate package-opening techniques, realistic uses of antimicrobials, simpler waste stowage, decreasing the number of packages involved, normalization of compressed bites, increasing the volume of each liquid, decreasing the size of the puddings, enlarging the capability to carry 3200 Cal/man/day if required, retention of thermal heating and cooling of the food till eaten - all became important factors. Additionally, flexibility to incorporate newer food types, such as meet chunks and high-nutrient cold liquids, necessarily must be considered.
It is, therefore, recognized that food acceptability involves not only the quality of the food itself and its variety but also the time and convenience of preparing and eating, size of portions, stowage, etc. The MOL Systems Office has recently evaluated this new feeding systems approach and feels it now offers maximum use of foods and packaging, more convenience, and, therefore, total acceptability. It also offers maximum flexibility for planning purposes and allows for in-orbit ease of readjustment if required.