Infant Milk Powder After γ-Irradiation and Accelerated Storage as an Indicator for Space Food Stability

At present, terrestrial food sources are used to provision astronauts for engaged in space missions confined to low Earth orbit. However, in the future, long-duration space exploration is planned for the Moon, and, beyond that, to Mars. Food for such extended missions needs a shelf-life of up to 5 years, a sustained nutritional and product quality. Space radiation can impact on such food, but little is known of what impact this could have on these materials. In this study, we evaluated the impact of radiation dosage and accelerated storage on infant milk powder (a formulated product consisting of proteins, fat, lactose, vitamins, and minerals), to evaluate its potential as an indicator for (chemical) space food stability. The milk powder was irradiated at different dosages (0, 2, 10, and 50 kGy) and underwent different storage conditions (20 or 50 °C for 0, 14, 28, 56, and 77 days), with subsequent color measurement and chemical analysis. It was found that γ irradiation had an impact on the milk powder’s color. It was speculated that this change was related to the Maillard reaction. Some changes were also found with the chemical composition, particularly, vitamins A and C, unexpectedly due to their susceptibility to radiation. Notable differences were not observed though for other components (vitamins, fatty acids, and amino acids). We conclude that infant milk powder shows great promise as an indicator of the impact of γ radiation, and accelerated storage, for (chemical) space food stability.