Bioregenerative life support space diet and nutrition requirements: still seeking accord

The capability of "dish" and "ingredient in dish" modeling to reduce the number of nutrition imbalances in bioregenerative life support diet was compared. Masses of dishes were assumed to be the independent variables in the 'dish' model, while in the 'ingredient in dish' model the independent variables were the total masses of the ingredients in a one-day menu and masses of ingredients in the dishes. The objective function in both models was minimization of discrepancy between the calculated nutrition intakes and the daily nutrition requirements of NASA for long duration space missions. Comparing of two models was carried out for the case of a one-day diet containing 12 dishes and 32 ingredients. It was established that the diet simulation by 'dish' model brings 6 nutrition imbalances. The use of the 'ingredient in dish' modeling has helped to reduce the number of nutrition imbalances to 3, namely, an excess of iron, vitamin A and saturated fat. Obstacles to the fulfillment of all nutrition requirements were the nomenclature and masses of ingredients in the dish recipes.