froze to the stars, pt finale

Today I decided to stop the great freeze-dry experiment. It’s been 17 days, more than twice the recommended time (though it did add “or so” to the end of “a week”), and I kind of need that freezer space back.

I took the tray out and set it on my stove to warm up for the afternoon. It yielded this.

Delicious.

Clearly this is one of those times where you write up the experiment report and the “conclusions” section reads “this did not work.” Kind of like my senior research in undergrad, actually, though at least there I got a beautiful graph of my active low-pass filter enhancing the sensitivity of the receiver.

Whereas in today’s experiment I get things like this:

That’s a soggy, folded apple slice. I didn’t taste it.

My hypothesis is that the inside of my fridge is too humid and too warm for this to be an effective home food preservation technique for me. There’s a lot of ice on the inside, it’s on the warm side for a freezer, and periodically I need to open it to remove food, letting in more warm air and moisture.

You’ll also note that only the potatoes turned black like the instructions said they would; the pumpkin and apple are still basically their original colors. An avenue for later exploration.

Though there is this one thing:

See that white part along the edge? That is a tiny, styrofoam-textured edging of what I’m pretty sure is freeze-dried potato.

It’s just that at the rate it’s going, full freeze-drying would take about five months. And I definitely need the freezer space back.

 

taste still on my lips, right or wrong

So it turns out that getting food for our space travelers of the future is only part of the problem. You have them pick their favorite meals… grow a fresh crop of cowpeas or strawberries or whatever… and then they get up to space and they don’t like their favorite food anymore, or something they previously disliked becomes delicious. Then you’ve got astronauts living on Mars and depressed because they hate all their food.

Okay, it sounds crazy. But the taste thing actually happens, and no one’s sure exactly why.

One possible explanation is nasal congestion. In microgravity, fluid in the body is redistributed to the upper part of the body, and the resulting fluid buildup can produce an effect kind of like having a head cold. As we all know, a bad cold can seriously interfere with your sense of taste, since smell makes up a significant part of your taste experience.

Astronaut Scott Parazynski told Scientific American (article also linked above) that while he believed in the nasal congestion explanation, the smells in the shuttle were also “distracting.” On the other hand, in the same article astronaut Clayton Andrews reported altered taste preferences though he was only congested part of the time.

Another possibility is that the food just gets boring after having to eat the exact same meal every eight days.

Regardless of why it happens, many astronauts experience a flavor dilemma in space. So spicy stuff is popular; for example, read this report from Expedition 16 commander Peggy Whitson about how important condiments are to her crew (motto: “It’s all about the sauce”). In 2002, Whitson (who loves shrimp on Earth but can’t stand it in space, with the reverse true for peanut butter) joked with the shuttle Atlantis that she “wasn’t opening the hatch unless they had salsa.” (They had salsa.)

With the possibility of touristy-type spaceflight edging ever nearer (at least for wealthy people), people are on top of preparing items for space consumption. Items like beer.

Yes, 4-Pines Brewing Co in Australia has produced a beer specially created for consumption in the taste-challenged non-atmosphere of space. It has a lower carbonation factor (since microgravity doesn’t allow the CO2 bubbles to be freed by burping like they can be on Earth) and, allegedly, stronger flavor for “astronauts’ less-than-refined palates.”

I couldn’t find any support for the idea reported in many of the space beer articles that taste buds are “numbed” by spaceflight or for the claim that taste loss is due to the tongue swelling (as reported in the Sydney Morning Herald), so if you turn up anything please share in the comments.

PS: On the moon, moon dust tastes and smells like gunpowder. On Earth, it smells like nothing (presumably they weren’t allowed to ingest the returned moon dust samples).

froze to the stars, pt II

On the last episode of Astronaut Ice Cream, Erin attempts to freeze-dry fruits and vegetables at home! Will she succeed?

< opening theme song >

My freezer isn’t that cold-stuff stays frozen, but I’ve encountered colder freezers- so I figured it might take a bit longer than usual to freeze-dry my veggies. So on Sunday I took out an apple slice to thaw and hopefully turn black. I set it on my counter on top of a paper towel and went back to listening to the Steelers game.

Several hours later, it was a bit damp and floppy. It was not, however, black. It was apple-colored.

Disappointing.

This morning (Wednesday) the plot thickened: I opened my freezer to get a couple of waffles for breakfast, and just to check on the slices I touched one of the apple pieces. And it was soft and foldable, like a piece of foam. It definitely was not apple-textured. Or frozen.

This particular apple slice was really, really thin-the slightly thicker apple and potato slices appeared to still be solid. I know my freezer is working because my waffles and ice and random things in bags are all still frozen. Maybe it needs another week. Maybe my freezer’s humidity is too high to pull this off.

I’ll check back with it next week to see how they’re doing.

Stay tuned!

froze to the stars above

Last week Amazon sent me email, which is not unusual. Usually it’s suggesting stuff I can’t afford to buy, or things which are similar to things I bought other people as gifts. Or things which are similar to my textbooks, that’s always a good one.

On this occasion, it was this:

Other than the astronaut ice cream, I don’t recall ever looking at anything in Amazon’s dairy and eggs department (because I didn’t know they had one).

While I have looked at astronaut ice cream, eaten astronaut ice cream, and named my blog after astronaut ice cream, I’ve never bothered to figure out what freeze-drying actually entails.

I have a handle on the regular kind of drying: the preformed water content in your food item evaporates, and then you get raisins or prunes or whatever.

As a side note, my eleventh grade English class once spent more than one class period arguing over whether the lines

What happens to a dream deferred?
Does it dry up
Like a raisin in the sun?

should have been “grape in the sun,” or if raisins had enough water content that they could continue to meaningfully dry up in the sun.

Anyway.

Freeze-drying, it turns out, is when you freeze the food and control your conditions so the water sublimates instead of evaporating.

NASA actually developed freeze-drying of food for feeding astronauts, and in fact astronauts still eat freeze-dried food.

While NASA might use a vacuum and/or radiation to freeze-dry, googling informs me that a more time-consuming version can be performed at home.

EXPERIMENT TIME.

I will use this method.

After the jump are pictures!

planted some beans

Recently in Senegal there was a conference: the World Cowpea Research Conference.

Seriously, I think there might be a conference for everything.

Anyway, google news coughed up a tiny flurry of stories about it, most of which focused on cowpeas’ potential as an effective African hunger-fighting crop. Awesome.

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!