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Heidelbaugh, N. D.

Publications and source records attributed to Heidelbaugh, N. D..

Hazard analysis of Clostridium perfringens in the Skylab Food System

The Skylab Food System presented unique microbiological problems because food was warmed in null-gravity and because the heat source was limited to 69.4 C (to prevent boiling in null-gravity). For these reasons, the foods were manufactured using critical control point techniques of quality control coupled with appropriate hazard analyses. One of these hazard analyses evaluated the threat from Clostridium perfringens. Samples of food were inoculated with C. perfringens and incubated for 2 h at temperatures ranging from 25 to 55 C. Generation times were determined for the foods at various temperatures. Results of these tests were evaluated taking into consideration: food-borne disease epidemiology, the Skylab food manufacturing procedures, and the performance requirements of the Skylab Food System. Based on this hazard analysis, a limit for C. perfringens of 100/g was established for Skylab foods.

Bourland, C. T.

Apollo experience report: Food systems

Development, delivery, and use of food systems in support of the Apollo 7 to 14 missions are discussed. Changes in design criteria for this unique program as mission requirements varied are traced from the baseline system that was established before the completion of the Gemini Program. Problems and progress in subsystem management, material selection, food packaging, development of new food items, menu design, and food-consumption methods under zero-gravity conditions are described. The effectiveness of various approaches in meeting food system objectives of providing flight crews with safe, nutritious, easy to prepare, and highly acceptable foods is considered. Nutritional quality and adequacy in maintaining crew health are discussed in relation to the establishment of nutritional criteria for future missions. Technological advances that have resulted from the design of separate food systems for the command module, the lunar module, The Mobile Quarantine Facility, and the Lunar Receiving Laboratory are presented for application to future manned spacecraft and to unique populations in earthbound situations.

Smith, M. C., Jr.

Space Shuttle food galley design concept

A food galley has been designed for the crew compartment of the NASA Space Shuttle Orbiter. The rationale for the definition of this design was based upon assignment of priorities to each functional element of the total food system. Principle priority categories were assigned in the following order: food quality, nutrition, food packaging, menu acceptance, meal preparation efficiency, total system weight, total system volume, and total power requirements. Hence, the galley was designed using an 'inside-out' approach which first considered the food and related biological functions and subsequently proceeded 'outward' from the food to encompass supporting hardware. The resulting galley is an optimal design incorporating appropriate priorities for trade-offs between biological and engineering constraints. This design approach is offered as a model for the design of life support systems.

Heidelbaugh, N. D.

Thermal preparation of foods in space-vehicle environments

Convection is the primary heat transfer mechanism for most foods heated in an earth-based environment. In contrast, in the low-gravity environment of space flight, the primary heat transfer mechanism is conduction (or radiation in the absence of a conducting medium). Conduction heating is significantly slower and less efficient than convection heating. This fact poses a problem for food heating during space flight. A numerical model has been developed to evaluate this problem. This model simulates the food-heating process for Skylab. The model includes the effect of a thermally controlled on/off heat flux. Parametric studies using this model establish how the required heating time is affected by: the thermal diffusivity of the nutrient materials, the power level of the heater, the initial food temperatures, and the food container dimensions.

Bannerot, R. B.

Heating of foods in space-vehicle environments

In extended space missions, foods will be heated to enhance the psychological as well as the physiological well-being of the crew. In the low-gravity space environment natural convection is essentially absent so that the heat transfer within the food is by conduction alone. To prevent boiling in reduced pressure environments the maximum temperature of the heating system is severely limited. The Skylab food-heating system utilizes a tray with receptables for the food containers. The walls of the receptacles are lined with thermally controlled, electrical-resistance, blanket-type heating elements. A finite difference model is employed to perform parametric studies on the food-heating system. The effects on heating time of the (1) thermophysical properties of the food, (2) heater power level, (3) initial food temperatures, (4) container geometry, and (5) heater control temperature are presented graphically. The optimal heater power level and container geometry are determined.

Bannerot, R. B.

Caloric balance during simulated and actual space flight

The in-flight caloric intakes of all Apollo astronauts are examined and shown to average about 25 kcal per kg per day. Measurement of weight changes following recovery indicates that about 0.15 kg of fat was lost per man per day in-flight for an average deficit of about 19 kcal per kg per day. Measurement of the caloric intake of astronauts under ground-based conditions and during hypobaric exposure indicated a caloric requirement which was not significantly different from the in-flight requirement adjusted for weight loss. Partial metabolic balance data and measurements of bone loss and body volume revealed that protein and mineral losses also occurred to an extent which would reduce the size of estimated in-flight caloric deficits.

Rambaut, P. C.

Nutrition systems for pressure suits.

Nutrition systems were successfully developed in the Apollo Program for astronauts wearing pressure suits during emergency decompression situations and during lunar surface explorations. These nutrition systems consisted of unique dispensers, water, flavored beverages, nutrient-fortified beverages, and intermediate moisture food bars. The emergency decompression system dispensed the nutrition from outside the pressure suit by interfacing with a suit helmet penetration port. The lunar exploration system utilized dispensers stowed within the interior layers of the pressure suit. These systems could be adapted for provision of nutrients in other situations requiring the use of pressure suits.

Huber, C. S.

Potassium food supplement

Potassium gluconate is considered best supplementary source for potassium. Gluconate consistently received highest taste rating and was indistinguishable from nonsupplemented samples. No unfavorable side effects were found during use, and none are reported in literature. Gluconate is normal intermediary metabolite that is readily adsorbed and produces no evidence of gastrointestinal ulcerations.

Bourland, C. T.

Preservation of flavor in freeze dried green beans

Before freeze drying, green beans are heated to point at which their cell structure is altered. Beans freeze dried with altered cell structure have improved rehydration properties and retain color, flavor, and texture.

Huber, C. S.

Microbiological testing of Skylab foods.

Review of some of the unique food microbiology problems and problem-generating circumstances the Skylab manned space flight program involves. The situations these problems arise from include: extended storage times, variations in storage temperatures, no opportunity to resupply or change foods after launch of the Skylab Workshop, first use of frozen foods in space, first use of a food-warming device in weightlessness, relatively small size of production lots requiring statistically valid sampling plans, and use of food as an accurately controlled part in a set of sophisticated life science experiments. Consideration of all of these situations produced the need for definite microbiological tests and test limits. These tests are described along with the rationale for their selection. Reported test results show good compliance with the test limits.

Heidelbaugh, N. D.

Food and nutrition studies for Apollo 16

A study has been conducted on nutrient intake and absorption during the Apollo 16 mission. Results indicate that inflight intakes of all essential nutrients were adequate and that absorption of these materials occurred normally.

Smith, M. C., Jr.

Apollo 14 food system.

The program for improving foods for use during space flights consists of introducing new foods and food-handling techniques on each successive manned space flight. Because of this continuing improvement program, the Apollo 14 food system was the most advanced and sophisticated food system to be used in the U.S. space program. The food system used during the Apollo 14 mission and recent space-food-system advances are described and discussed in regard to their usefulness for future manned space flights.

Smith, M. C., Jr.