While researchers will likely pore over the HI-SEAS crewmembers' journals for a while to come, some conclusions are already apparent to Vermeulen.
"Ingredients that will be essential for future space missions on Mars or the moon will include spices, herbs and hot sauce," Vermeulen told Astrobiology Magazine's Leslie Mullen during the mission. "But also comfort food such as Nutella, peanut butter and margarine. And then enough ingredients rich in fiber. The problem with shelf-stable ingredients is that they're usually highly processed and hence lacking fiber. We enjoy wheat bread, rye crackers, nuts, and dried fruits, for example."
While food was the main focus of the study, the HI-SEAS crew did more than just cook and eat. For example, they ventured outside the habitat at least once per week to explore the terrain and perform geological and microbe-detection studies (donning spacesuits, of course, in keeping with the Mars mission theme).
HI-SEAS isn't the only food-related study NASA is funding in connection with its Mars ambitions. For example, the space agency recently awarded $125,000 to a researcher seeking to develop a "3D pizza printer," which could synthesize a variety of foods using ingredients with a long shelf life.