Tholins are a wild mix of thousands of different organic chemicals. Deposits of tholin on planetary surfaces is thought to be common throughout the universe, because the elemental precursors of tholins and the energy to make them are common thru the universe. Titan is covered with thick deposits of tholin. Depicted: cracks in Europa, crammed with tholiny goodness.
Bacteria can eat tholin.
Tholins have been a scientific pet project for decades. “This tholin
material has been made in labs for about forty years, but the stuff is
so complex that we couldn’t analyze thoroughly until recently,” says
Dale Cruikshank, an astronomer and planetary scientist at NASA's Ames
Research Center. Now they know that when you hydrolyze tholins, those
complex bonds between hydrogens, carbons, nitrogens, and oxygens can
recombine to form amino acids.
Nobody knows exactly how life got started, but most scientists agree
that amino acids were probably involved. “It’s also edible, in a way.
People have made the this stuff and exposed it to different kinds of
bacteria, and some can metabolize and even thrive on it,” Cruikshank
says. "To me, that drives this connection to pre-biology even closer.”
So, tholin soup, anyone?
So too your scientists! Now - tholins probably contain a lot of stuff that is not good to eat. OK, mostly not good to eat. But there are amino acids in there, and those are good to eat!
Presented with enormous mounts of tholins, your castaways could
1: Use science to purify the amino acid fraction. Then chow down. Even if it is only 0.1% they have mountains of the stuff.
2: Grow yeast or bacterial on tholin slurry, rinse off unmetabolized tholins, and eat the bugs.
3: Warm up the tholin to drive off the worst stuff, eat the rest and hope for the best.
4: Give up on 1 (too hard), 2 (making grow vats did not work) and 3 (one time project). Instead, distill off volatiles, retaining only the ethanol fraction. Get drunk. Wake up; repeat.
In unexpected discovery, comet contains alcohol, sugar
"We found that comet Lovejoy was releasing as much alcohol as in at
least 500 bottles of wine every second during its peak activity," said
Nicolas Biver of the Paris Observatory, France...
Ethanol has plenty of caloric value. Your tholin brew will have piquant notes of ethanol, ammonia, melamine and hexane.
Korolev looked appraisingly at the clear fluid in the beaker, tilting it
back and forth. He took
a careful sniff. He lifted an eyebrow. Then he raised the beaker in a
silent toast to his crewmates and downed the whole thing in a gulp.
He ran his tongue over his teeth, regarded the empty beaker
phlegmatically and nodded. "A little ice will help."