I am SO sorry for failing to entertain people. I had vacations to go on, job interviews, and a busted computer, but I suppose I should have made blogging more of a priority than, say, paying attention to my child. Or feeding my husband.
Anyway, I have a blog post now. It's about how much fun it is to use chemistry without really understanding it. This is illustrated best by late-summer preserving. Specifically, jam, jelly, mead, pickles and sauerkraut.
See, I KNOW that fruit contains this thing called pectin, and when it's heated to the right point (223F last I checked, I think) pectin will make jams and jellies set. The trick is finding fruit that's the right degree of ripeness (or not ripeness) so that the amount of sugar you have to add to get the temperature to go that high doesn't make the jam or jelly taste disgustingly sweet, and that contains enough pectin anyway. (Yes, I spurn the pectin you buy in a box in the grocery store. It makes jam too hard, and flavourless. As an aside, people who make "low-sugar" jam belong in the same rung of hell as the low-fat dairy types.)
The mystery is, I have NO idea why pectin does that. I don't know if it forms some sort of crystal lattice or expand-o-starch molecules or what. I tried to read the explanation on wikipedia and bailed out after "The characteristic structure of pectin is a linear chain of α-(1-4)-linked D-galacturonic acid that forms the pectin-backbone, a homogalacturonan." I decided I like it better as a mystery. You take fruit, you take sugar, you throw them together on the stove, and at some point, you get jam. If you screw up and jar it before it's really done, you can always go back and boil it up again and fix it. Unripe fruit has more pectin, so picking fruit for jam is fun because you can go to places that other people have already been to and still pick lots, AND if you happen across a really ripe berry or fruit, you can just munch it up secure in the knowledge that your gluttony is helping your jam set. What could be better?
The mysteries of pectin are nothing, however, to the mysteries of lactobacteria. GERMS!!! yay. And they make pickles for you. People who are afraid of germs haul out their canning equipment and vinegar and whatnot and have to wait, like, 3 months for their pickles to be ready. Me, I love germs. I wash little bitty cucumbers and stuff them in a jar with salt water, garlic, dill and grape leaves. (Another lovely alchemical mystery. Actually no, a lack of alchemical mystery... the grape leaves stop the cucumbers from going mushy.) I stick them in the pantry with the jar lids on lightly to prevent unfortunate explosions and typically bugger off on vacation for a week. When I come back, they have magically turned into pickles. Intellectually I know that salt-tolerant lactobacteria are responsible, but I don't know what the bacteria actually DO. What part of the pickles do they eat? Why do they turn sour? Is that like eating bacteria poop? I don't understand. But I don't have to - that's the good part. I trust my bacteria. They make things tasty and good for me. And then I eat them. Ha ha ha! (Sauerkraut is even easier. Shred cabbage, mix with salt, pound into jar, wait.)
The mead part I actually understand. Yeasts are easier, somehow. Wee beasties that eat sugar, fart carbon dioxide, and pee out alcohol. So I kind of get the science on this one, but it's still really fun to just mix honey and water and watch it get all foamy and bubbly. Sourdough bread is similarly entertaining, except when I forget I left some rising and I come back and it's like some sort of slime mold crawling all over the oven, mocking my attempts to keep the damn thing clean.
I just think this stuff is so FUN. It's like nature has all this fantastic food ideas just waiting for you, and you just have to mix it right and then leave it alone. No other animal could have discovered these things. The kind of ingenuity and willingness to put food that microorganisms have tampered with in our mouths, and claim to enjoy it, is what makes humans really special. Also, the patience to wait it out and let perfectly good food get munched on by microorganisms first. I don't see raccoons, for instance, waiting for things to start fermenting in the garbage before knocking it over. Never mind that getting into outer space stuff or those nuclear reactors - the fact that ordinary humans can team up with things they can't even see to make food tastier and last longer is pretty remarkable.