When it comes to imagining food in space, the first thing that probably comes to mind for most people is frozen products like astronaut ice cream. And while preserved foods will inevitably be a part of astronaut diets for the foreseeable future, there is currently a growing focus on how to provide astronauts with fresh foods such as vegetables and grains for the most less occasional food.
Eating fresh foods is important not only for physical health reasons, but also for the mental health of astronauts. Repetitive, processed foods can be unsatisfying and lead to what’s called menu fatigue, where astronauts don’t want to eat because they’re sick of the same meals over and over again. And that can be a real problem when astronauts lose weight and don’t get enough nutrients.
Fortunately, we are getting better and better at growing a wider variety of foods in the microgravity conditions of space. For the past few years, astronauts on the International Space Station (ISS) have been growing foods like radishes, lettuce, and peppers. And now, a group of researchers has developed an “astronaut salad” with foods that can be grown in space.
The salad, created by researchers at the University of Adelaide in Australia and the University of Nottingham in the UK contains the following ingredients: soybean, poppy, barley, kale, peanuts, sweet potatoes, and sunflower seeds. The exact amount of each ingredient is adjusted so that it provides the nutrients an astronaut needs as measured by a 2011 NASA study, – and so that it tastes good too.
“We simulated a mixture of six to eight plants that provide all the necessary nutrients that an astronaut needs, which is different from what people on Earth need,” one of the researchers, Volker Hessel at the University of Adelaide, said in a statement. “While there are many plants that can meet the nutritional needs of an astronaut, we need to find those that can pack a punch and provide the calories needed in small portions that can be planted in a small space.”
The researchers used a computational model to help them balance the nutritional needs of the astronauts, working from a list of more than 100 plants that would be suitable for growing in space. These are foods that can grow in a small space, in a hydroponic system, and require little fertilizer.
To keep the food attractive, researchers chose plants with different colors, textures, and flavors. “Diet is an important part of staying healthy and happy, and there are many factors that contribute to this,” said one of the researchers, Shu Liang of the University of Nottingham. “As well as the nutritional values and the ability to grow plants in space, we also look at other important aspects of a space meal to improve the astronaut’s well-being, including color, taste and simultaneously food.”
A group of volunteers tasted the salad and seemed happy with it, with one saying they “wouldn’t want to eat it all week as an astronaut.”