How do condiments improve space meals?

Condiments significantly enhance the palatability of space meals. In space, food often tastes less flavorful due to fluid shifts creating sinus pressure similar to having a cold, the lack of gravity affecting how smells reach the nose, or the artificial atmosphere. As a result, astronauts frequently crave strong-flavored condiments like salt, pepper, Tabasco, mayonnaise, and taco sauce to make their food more enjoyable. In fact, such is the importance of taco sauce that it once became a form of currency among astronauts during shuttle flights for trading tasks and favors 1.

For a deeper understanding, consider listening to the Space Food Currency episode from the EconTalk, featuring Zach Weinersmith.