Various images of the developing world suggest that clean drinking water is appreciated. Not all locales have sources of above ground running water.
There is a variety of starch than can absorb 2000 times its own weight in water [link]. I think a simple technology, where you dig a slight hole, then put some of that stuff, possibly atop a mesh for cleanliness where it pulls moisture from the soil and dew (overnight) would produce a gooey mass that could be eaten to fully hydrate a human. 1/2 a gram would be sufficient to gather a liter of water.
Now, if this starch can be produced at $2/lb (454g) then it is near 1/10th of one cent to fulfill the drinking water requirements of a human at the developing world.
It gets better though. They could test it on goat/human urine. Does it merely absorb the urine or does it separate the ions to outside the gel making an edible “drink”? This could provide an easier point source for gathering water than soil/dew.
Also, if you put it in milk, does it absorb the water making “instant curds” or something like wet powdered milk out of regular milk?-- beanangel, Oct 16 2017 USDA report on starch that absorbs 2000 times it weight in water https://naldc.nal.u.../download/26332/PDF [beanangel, Oct 16 2017] Superabsorbant Polymer https://en.wikipedi...erabsorbent_polymer [FlyingToaster, Oct 16 2017] Water tree https://en.m.wikipe...erminalia_elliptica... and a video of a tree being tapped [EnochLives, Oct 16 2017] Road Jelly http://news.nationa...ime-oregon-highway/Fish+car=jelly [mylodon, Oct 16 2017] So ... all the effort of toilet-training your goats to use the right spots would be amply rewarded by a generous serving of goat- piss porage, which might or might not have been meaningfully filtered?
Mmm ...-- pertinax, Oct 16 2017 Is it safe to eat?-- mylodon, Oct 16 2017 This might work. However, my instinct tells me that a starch gel will absorb other small molecules besides water. Some water will be absorbed as a hydration shell around the starch, but the gel will also contain large pores that will absorb water plus gloop.
Starch gels were once used for separating DNA and other molecules by electrophoresis, so it certainly doesn't exclude those molecules.
It would probably exclude bacteria, though, and maybe even viruses. But probably not heavy metals, urea and other tiny things.-- MaxwellBuchanan, Oct 16 2017 Good for stiffening shirts. (not that I own any shirts)-- xenzag, Oct 16 2017 This could be placed in lines on roadways to collect floodwater and slow traffic.-- mylodon, Oct 16 2017 There are some plants that accumulate and store large amounts of water, purifying it in the process. Some rainforest vines (possibly rattan, but I'm not sure) store so much water that you can cut a section and pour the water out. There's also a desert plant that stores water in a huge underground tuber.
Such plants would be a better option, since they (a) are renewable and (b) purify the water as they absorb it.-- MaxwellBuchanan, Oct 16 2017 //Such plants would be a better option, since they (a) are renewable and (b) purify the water as they absorb it.//
They also are capable of reproduction. Plant 50 and next year you'll have a hundred.-- Voice, Oct 16 2017 Unless the Monsanto bastards get there first....in which case you’ll have to pay through the nose to purchase new seeds each year.-- xenzag, Oct 16 2017 Aka the stuff they put in diapers?
How do you convince it to let go of the water its absorbed once you've eaten it?-- RayfordSteele, Oct 16 2017 sprinkle salt on it.-- mylodon, Oct 16 2017 [bean] old umm bean, the substance isn't starch, it's a polymer grafted onto a starch. Not edible.
But, I think it'd be cool to dig a shallow trench, toss in some powder and seeds, then pee in it. That's presuming of course that roots will wick water away, while the surrounding dirt won't.-- FlyingToaster, Oct 16 2017 i thought about adding some color to it so the color would look right when it was completely full of water. If you eat it before it is full of water it could take water away from the human ingesting it.-- beanangel, Oct 16 2017 I wonder if it would be possible to explode somebody by replacing the contents of medicinal capsules with super-absorbant, high-expansion polymer?-- MaxwellBuchanan, Oct 16 2017 If you had a highly absorbent teaspoon of something. And then applied one cup of water. You'd have a cup of water mixed with a teaspoon.
1 cup+1 teaspoon = not exploding.
If you mixed it, and it absorbed air using the water as catalyst
1 cup+ 1 teaspoon + 24 cubic meters of air
by those calculations, you would explode.-- mylodon, Oct 17 2017 what happens if you eat some that has not absorbed its full capacity of water? do you turn into a raisin?-- bob, Oct 22 2017 random, halfbakery