Apparently, one of the things Matt has "always" wanted to do is make yogurt. Intrigued myself, we decided to give it a try. Hey, I figured, it's a new craft (science?) project, I like yogurt, and I like the idea of having half a gallon of yogurt for the price of half a gallon of milk. There are ample resources on the internet giving you instructions for how to do it yourself without a kit, though most of them disagree with each other. Our first batch came out better than expected, which is to say it was edible. Though it did rather look like viscous milk.
But here's what I've find intriguing. I suppose I'd already entered into a certain category of "like to bake, time to bake, frugal, homemade kind of people" because I make my own bread--in the bread machine, of course--and granola (less sugar). But once you start playing with cultures (beyond yeast)...my friend, you've entered a whole new realm. Since moving to this small town, I've met people who make their own kambucha, a fizzy, sugary tea that's supposed to help your digestion and possibly save the world; people who make a kind of fermented vegetable salsa, which involves sitting and fermenting on your counter for at least 2 weeks and has similar proposed properties; people--several people--who brew their own beer. I have yet to try those first two. Once you enter the world of foodery, you just keep going deeper and deeper, it seems. I find that delightful.
If you're interested in making yogurt, a google search is all you need. Here are the basics:
1) Heat milk without boiling it until it is 175-180 degrees. You may want to add milk powder or even gelatin to thicken it.
2) Cool milk down to 130 degrees. Add 3 or so tablespoons of plain, store-bought yogurt (for the first batch) that has live culture in it. Pretty much all yogurts do.
3) Stir it up, and place it somewhere that it can stay at 110 degrees for the next 7 hours or so, longer if you like more bitter yogurt. Every site has its own recommendation, from crockpot or oven (if you can keep it warm enough) to wrapping it in towels (which we tried and doesn't stay warm long enough) to setting it on a medium-setting heating pad (which sounds like a good idea but calls for lots of electricity), etc. A friend from Indian said you could just set it on the counter for a few hours. Then again, where he's from, it's a lot hotter. I'll bet, if you keep it in direct sunlight, it might be almost warm enough. November in Wisconsin, not so much.
4) When it's done, stir it up to stop to bacteria from doing their thing and leave it overnight in the fridge.
5) Eat and enjoy. Don't be scared of greenish liquid. Just mix it back in.
What a fascinating world.