Recently in Senegal there was a conference: the World Cowpea Research Conference.
Seriously, I think there might be a conference for everything.
But into those stories crept a paragraph along the lines of this one from ScienceDaily:
Even the National Aeronautics and Space Administration (NASA) is on the cowpea bandwagon. With the plant’s ability to produce nutritious leaves in only about 20 days, NASA scientists are considering sending cowpeas to the international space station, where they could be cultivated to provide food for astronauts.
NASA has cowpea studies available from the 90s, and has more recently been testing their LED space lighting arrays on crops which included cowpeas, so I personally wouldn’t apply the term “bandwagon.” “Renewed interest,” perhaps.
Cowpeas are protein-licious (about 25% protein), which might come in handy considering that livestock would be even trickier to handle in space than a greenhouse. The quote above is probably based on this 1996 study by Ohler et al at the NASA Specialized Center of Research and Training in Bioregenerative Life Support at Purdue, which concluded that a 20-day harvest cycle was most efficient for food production… if you ate the plant itself, instead of cultivating it for beans.
This entertains me especially considering that the ScienceDaily article described the vegetative portions of the plant as “leaves and stalks that serve as especially nutritious fodder for cows.” I mean, yes, that’s why it’s called cowpea, but still. Ohler et al inform us that the leafy parts are nutritious for the Homo sapiens in the audience as well:
Like the protein in seeds, cowpea leaf protein complements that of cereal grains (Maeda, 1985). Leaves also are a good source of minerals, specifically Fe, Ca, K, and Zn (Imungiand Potter, 1983). Raw leaves are high in vitamin C, carotene, and folacin, although 80% of these vitamins can be lost during cooking.
One of the problems mentioned in the above news articles as facing earthbound cowpea cultivation is weevils, which eat the dried beans when they’re being stored in traditional bags. One remedy, ScienceDaily says, is
a three-layer plastic bag that shuts off the oxygen required to fuel a weevil population explosion.
You know what else shuts off oxygen? The vacuum of space.
While I regret the missed opportunity to write about space weevils, I doubt that cowpea weevils will be a big problem for astronauts. Though it did make me wonder: you know how when it’s really cold out you can just store stuff from your freezer on the porch/windowsill/roof? I mean, unless it would attract bears or raccoons or something. Which are also not a problem in space. Is there anything to prevent astronauts from hanging their food stores on the outside of the ship, aside from the access issue? Is there a reason to do it? It would free up room inside. But what if your food was hit by a meteoroid?
I kind of want them to try anyway.
By the way, the cowpea is also called the black-eyed pea.
…Look, there are a lot of way more annoying Black Eyed Peas songs I could have chosen. This one even included a guy in a spacesuit. Relevant!
When I think of food in space, I think of things like astronaut ice cream, sold in fine science museums everywhere.
It looks delicious, right?
Um, right. I like it, but it does have a texture weirdly reminiscent of styrofoam and sometimes it makes my teeth feel strange.
But it seems that “food in tubes” is no longer an accurate description for what astronauts have to eat. (Project Mercury astronauts weren’t so lucky) Modern astronauts even get some fresh food, though they have to eat it in the first couple days since there’s no fridge on the space shuttle.
All this revolves around the idea that astronauts take all their food with them. While that might work for hanging out close proximity to Earth for a limited period, it’s not really workable for a trip to, for example, Mars. Especially if you wanted to stay on Mars for a while.
At this point farming sounds like a good plan for food production. And it is, if you can overcome issues like “microgravity inside a spacecraft won’t hold the plants down,” “there is no sunshine inside the spacecraft,” and “where is the rain going to come from.”
People are working on that.
Like these people:
I want to know what happened to those strawberries after this photo (larger version). Did they go splat sadly on the floor? Did anyone apply the five-second rule? They look delicious even airborne and blurry.
This is Gioia Massa, Cary Mitchell and Judith Santini from Purdue University, who studied a variety of strawberries with the goal of determining which of them might be most suitable for space growing. They did this by comparing three strawberry types (Tribute, Fern, and Seascape; I had no idea strawberry cultivars had names like roses do) when the strawberries were given different amounts of light: 14 hours a day, 17 hours a day, or 20 hours a day.
After this test, Seascape “was the most consistent producer, typically with the largest, most palatable fruit.”
To figure the palatability, they had volunteers rating the deliciousness of the strawberries. Sign me up.
Anyway, after this initial experiment, they grew Seascape again at 10, 12, and 14 hours of light daily for 33 weeks, finding that “Photoperiod again had no significant effect on total fruit weight…” meaning it put out the same total amount of fruit regardless of daylight. Less light meant fewer individual fruits, but they were larger. Using less light means using up less energy, an important consideration when you’re on a space ship.
Fewer individual fruits also means the astronauts have to do less work. Bonus.
So the (NASA-funded) quest to grow space strawberries marches on. Mitchell and Massa plan to look at Seascape’s response to LED lighting, hydroponics growing, and different temperatures next.
Mitchell pointed out that strawberries might be the only sweet space crop being considered. I hadn’t thought about it before, but the others he lists – radishes, tomatoes, lettuce – are, well… veggies. Except for tomatoes, technically. They’re good for you, but does anyone look forward at the end of the day to a nice leaf of lettuce? Or a radish? Going to Mars is cool, but it’s pointless if you’ve gone insane from food monotony by the time you get there. Strawberries might help with that.
The article: Gioia D. Massa, Judith B. Santini, Cary A. Mitchell, Minimizing energy utilization for growing strawberries during long-duration space habitation, Advances In Space Research, February 2010; doi:10.1016/j.asr.2010.02.025