Safety issues associated with processing soybeans in an enclosed habitat intended for long-duration space missions

Soybeans have been selected to be grown in a habitat (BIO-Plex, Bioregenerative Planetary Life Support Systems Test Complex) designed to evaluate advanced life support systems for long-duration space missions. Soymilk and soy bread will be incorporated into this nutritious, plant-based food system. Because all consumables will be recycled and reused, food safety is a particular concern. Critical control points were identified to control microbiological hazards, particularly mycotoxins, and chemical hazards from antinutrients and volatiles emitted during processing of soymilk and soy bread. Volatile compounds, evolved during the manufacturing of soymilk and soy bread, were quantified by GC/MS to assess their impact on this closed loop system. All concentrations of volatiles evolved during soymilk production were below the 24-h Space Craft Maximum Allowable Concentration (SMAC), while acetaldehyde surpassed the SMAC criteria for soy bread. Recommendations were made for processing of soybeans in such environments to minimize risk to crew member health.