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Most people’s experience with space food is limited to the vacuum packed slabs of freeze-dried Neapolitan ice cream sold in science gift shops.

In fact, that “space ice cream” never made its way into space. NASA deemed it too crumbly, a problem to think about when developing food to eat in space as rogue crumbs can cause serious consequences in zero gravity, also called microgravity.

It took 12 years after the first bite was ever consumed in space for ice cream to make its debut in microgravity, according to NASA. The history of space food has been a long and appetizing road.

In the beginning

With the challenge of developing food to eat in microgravity, scientists were faced with basic questions such as could food be digested easily? Or how would it react to extreme pressure and vibrations during launch?

A strict checklist was followed. Food must be crumble-free, lightweight, easy to prepare and consume, long-lasting with no need for refrigeration and nutritious enough to sustain an astronaut throughout their space duties.

The first meal eaten in space was in the spring of 1961 by Russian cosmonaut Yuri Gagarin. He had pureed meat in a squeezable toothpaste-style tube, followed by a tube of chocolate sauce. The following year, NASA celebrated John Glenn becoming the first American to eat in space, squeezing puréed beef with vegetables from an aluminum tube, among other edible delights.

Glenn and his fellow Mercury astronauts were among the first to test the physiology of eating in microgravity environments. For these experiments, they were given food in fairly unrecognizable forms. In addition to semi-liquids in tubes, NASA offered crushed cornflakes and crushed wheat molded into bite-sized cubes which were then coated in gelatin so they didn’t crumble.

They also took vacuum packed freeze-dried foods. The process of freeze-drying food retained its nutritional value, required no refrigeration and resulted in it being incredibly light and compact. However, rehydrating the food packages was a cumbersome process in microgravity. Water was injected through a nozzle, the pack was kneaded to reconstitute the food then squeezed directly into the mouth through an opening. After consumption, germicidal tablets were put inside the empty pack to discourage microbial growth, the agency said.

During his 34-hour Mercury mission, the longest of its kind at the time, astronaut Gordon Cooper ate a meal of dehydrated shrimp, potato salad and apple juice. At his post-flight press conference, Cooper remarked: “I think the food I had along was adequate, although it was so much work to get to some of it here, that I tended to just perhaps not eat as much as I should have.”

Pastes in tubes and bite-sized cubes from the Mercury and Gemini missions in 1961-1969.

By the mid-1960s missions were longer, up to two weeks, and eating was less experimental and more for nutritional sustenance. At the same time provisions had to be made with smaller weight and mass constraints. According to NASA, the food system for each astronaut per day on Gemini 7 was limited to 0.77kg, or 1.7 pounds, and 110 cubic inches in volume, which had to include the food packaging.

Out of this world

By the time man had made it to the moon on the Apollo 11 mission in 1969, eating in space had made its own giant leaps. As reported by the National Air and Space Museum, rations were increased to 2,800 calories per day and hot water dispensers were installed so meals no longer had to be room temperature. Gone were the days of squeezing pastes from a tube; improved packaging reduced meal preparation and consumption time.

Also a new form of food was introduced known as “wetpacks.” These thermally-stabilized, ready-to-eat meals didn’t need to be rehydrated as they retained their water content. Wetpacks quickly gained crews approval which was enough for NASA to justify the additional weight resource. They even let astronauts eat with a spoon.

Wetpack foods were appealing as they more closely resembled the consistency of regular food albeit a bit stickier so that food held together better without bits floating off. Among the wetpack foods eaten by the Apollo 11 astronauts were spaghetti with meat sauce, sausage patties and chicken stew, according to NASA.

Another type of thermostabilized container was offered: a can with a ring pull lid, although these canned products weighed approximately four times that of freeze-dried foods. The modernized packaging meant that storage space was reduced. A week’s worth of food for one astronaut fit into a container the equivalent size of three shoe boxes, according to NASA.

Astronauts now had some flexibility to their strict meal plans with the introduction of the pantry concept, where beverages, soups, desserts and bite-sized foods supplemented pre-packaged meals. By now the agency was offering the Apollo 11 moon-walking astronauts had more than 70 food items to choose from. Among the foods that were eaten on the surface of the moon in the lunar module was beef stew, bacon squares, date fruit cake and grape punch.

Astronauts roaming the lunar surface also had drinking devices with water installed in their space suits, and if they were peckish they could nibble on the high nutrient food bar in their helmet, as reported in NASA’s Lunar Surface Journal.

For all the advances in space food achieved during the Apollo food program, the food scientists agreed that the majority of Apollo astronauts returned to Earth having lost weight for not consuming sufficient nutrients.

The golden age

In 1973, NASA launched Skylab, the first space station that allowed astronauts to stay in space for weeks and, eventually, months, at a time. By this point the importance of providing food with familiar flavors and textures was known to support astronauts psychological well-being. For this reason, NASA installed a dining area on Skylab. Instead of chairs, footholds allowed the crew to congregate around a table and eat their meals in a familiar setting.

Where previous spacecraft used fuel cells that produced water as a by-product, which then could be recycled into the food system, Skylab used solar cells for power, so foods that needed to be rehydrated were restricted.

Skylab was the first time NASA sent a dedicated food storage refrigerator to space. It held frozen food, which proved to be the most popular to crews because of its resemblance to Earth food. To heat meals, the crew used a food warmer tray, a tidy contraption with separate compartments that used conduction to heat meal packages. During the Skylab missions, ham, chili, mashed potatoes, steak, asparagus and, of course, ice cream were all on the menu.

The Skylab food tray with individual heated canned food compartments.

What are they eating in space now?

The International Space Station has been continuously inhabited since 2000. Typically, three to six astronauts and cosmonauts stay for a period of six months in an area no larger than a six-bedroom house. Around six months before launch, astronauts spend a number of days tasting and rating a menu of 200 food items at the Johnson Space Center Food Lab. According to Jennifer Levasseur, curator at the Smithsonian National Air and Space Museum, each astronaut has a tray assigned to them packed with their food so they can decide what they want to eat for each day from their stash. They can even trade with other astronauts, she said.

They can also request snacks, entrees or even favorite condiments off the standard menu for their personal “bonus container” as long as they comply with microbiological and shelf-life requirements. “They can also ask for special items like spreads (one of them is a big fan of Fluff),” Levasseur said. The most commonly requested items is tortillas, she reports, perhaps because NASA only allocates one per day.

Nowadays, on the ISS, the US provides about half of the food, and other countries, primarily Russia, provide the rest. Around 50% comes in thermostabilized form, but also in freeze-dried, irradiated and natural form. Astronauts don’t have to bring their entire six-month food supply with them on arrival to the ISS as resupply vehicles visit every few months.

The only refrigerator on board the ISS is used to store biological experiments so all food has to be shelf stable for a minimum of 18 months, although a small chiller has been brought up so astronauts are able to drink chilled beverages.

Food can taste different in space. The lack of gravity causes a phenomenon known as fluid shift, leaving the head feeling congested, which in turn affects the sense of smell and taste. Aromas also dissipate differently. They don’t rise and disperse as they would here on Earth, further inhibited by packets containing the food means aromas don’t reach the nose as readily.

For this reason, NASA says that astronauts tend to have a preference for spiced food, there are plenty of condiments on the ISS, all come in liquid form. Pepper is suspended in oil and salt is dissolved in water both added to food using dropper bottles.

Martian food

Planning food for a manned mission to Mars makes shelf-life a major issue. Currently food on the ISS has an 18-month to three-year shelf life. But this will need to increase to five years because of weight restrictions, food will likely be shipped separately ahead of the crew.

“It might be sitting out there for a while before the crew even gets to it and starts eating it, it might be five years old by the time they’re consuming the last rations before they come back to Earth,” said Grace Douglas, Advanced Food Technology Lead Scientist at NASA’s Johnson Space Center.

So how on Earth do you get food to last for five years?

“We have studies in this area that are looking at combining better formulations, with better packaging, with a better process and then with cold storage,” Douglas said.

NASA has also been exploring growing food in space. They have successfully grown food in a microgravity environment and a water-limited environment. In 2015 the crew of the ISS became the first to consume food grown in space: red romaine lettuce.

“You’d have to get to a point where you are growing these foods in a very robust system, where you’re positive that you’re not going to have a crop failure,” Douglas said.

Experiments are focused around food being grown as a supplementary system.

“The first crops are likely to be more of a ‘pick-and-eat’ salad crop, like lettuce, tomatoes, green onions or green peppers,” Douglas said.

One thing is for sure, plants will be integral for successful manned mission to Mars not only for nutrient consumption but for creating oxygen and processing waste gases.

Food doesn’t necessarily need to be sent in its final, consumable form. NASA is looking at creating a system that uses elemental component like nutrients, to make food, a bit like a 3D food printer, to save on mass and weight.

As Douglas describes, “it would store nutrients in more stable, dried forms which a computer can use to print in very precise ways into a food specifically for individual crew members.”

Perhaps they’ll be able to print space ice cream too.

The Vegetable Production System known as 'Veggie' deployed on the International Space Station to produce salad-type crops, in this case red romaine lettuce. The system uses highly efficient, long-lasting and low heat LEDs.