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Friday Fun Thread for November 4, 2022

Be advised; this thread is not for serious in depth discussion of weighty topics (we have a link for that), this thread is not for anything Culture War related. This thread is for Fun. You got jokes? Share 'em. You got silly questions? Ask 'em.

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Staring at orange juice in confusion...

Googling to try to fix confusion...

Looks like the rate of decay depends very highly on temperature and pH? So in cool acid in a citrus fruit, it's fine; in warm (or boiling!) neutral water in a veggie pot, it's gone?

Just going off memory, but I think non freshly-squeezed orange juice actually doesn't really have much vitamin C left. The big producers have to add it back in, along with orange flavoring, before packing and shipping, but they're usually mostly gone again by the time it hits your glass. The reported levels of C are at packing, not at drinking.

Decay seems to depend on everything, heat, pH, sunlight, oxygen, etc. Seems almost amazing that vitamin C exists at all.

Skyforger's summary is correct; if you're curious about how the cure for scurvy got "undiscovered," this blogpost from some years back is fascinating reading.

arctic explorers kept getting scurvy, and the traditional citrus and so on didn't help as they pre-squeezed the juice before embarkment to preserve it, destroying the vitamin C over the next few weeks. So they concluded the whole 'citrus cures scurvy' thing was an old wives' tale and the disease must be due to some contamination of their food supplies, so they scrubbed and sanitized everything to no effect.

Fresh seal/dolphin/whale skin has some C in in though, so when they finally hunted fresh meat in desperation and the scurvy went away, they concluded it must just be a really damn stubborn contamination in their meat supply making them sick. Interesting example of a clearly-effective discovery being 'undiscovered.'

Yeah, a lot of organic material depends on how its twisted up (conformation), and the shape is governed by a bit from over here being attracted to a bit from over there due to ionic charge, hydrogen bonding, etc.--things that are not standard atom-atom covalent bonds. Those secondary types of linkage either form more easily or get disrupted more easily depending on pH, temperature, and solvent type. Something is "denatured" when its useful twisty conformation is untwisted, which makes it not useful. Depending on the organic material you're talking about, sometimes restoring it to a friendly environment will cause it to re-twist back into its useful conformation, but other times the sticky pieces just glom onto matching sticky bits elsewhere and you just get a mess. (A lot of cooking is based on this process; intentionally denaturing some components of ingredients using acid/heat/water, and then cooling the result into a different state.)