Those who read my blog with any regularity are probably sick of hearing me sing the praises of Stephanie the Crockpot Lady ----I don't know if I've ranted much about her here on dreamwidth yet, but there ya go. (crockpot365.blogspot.com )
A month or two ago I became intrigued by her method of making yogurt in the crockpot: crockpot365.blogspot.com/2008/10/you-
The first time I tried it, it worked well, although it was very runny and didn't strain well. (That was the time I followed her directions pretty much to a T.) The end result was better suited to "kefir" (that yogurt drink you pay an arm and a leg for at Whole Foods) than any more traditional yogurt.
The second time I tried it, I made a gallon instead of a half gallon and threw in some powdered milk as well--the basic method I used:
- heat a gallon (Stephanie did 1/2 gallon, so I'm adjusting) milk in crockpot on low for 2.5 hours
- unplug crockpot and let sit another 3 hours
- whisk a cup of plain yogurt in a bowl; whisk in a cup or three of the warm milk till it's nicely mixed, then pour back into the crock. (Here I added a cup of powdered nonfat milk.)
- Cover the crock, drape a couple of heavy towels over it for insulation, and let sit unplugged overnight.
This time I immediately strained it, putting a piece of natural muslin (from my fabric stash, prewashed of course and dampened before dumping the yogurt in) into a vegetable strainer over a big pyrex measuring container--I used a measuring container because I was curious about how much whey would actually drain out. Also, every 10 minutes or so I scraped the muslin with a spoon, to clear away the already strained stuff and make room for more; not sure how big a difference this made.
The strainer held about a quart of unstrained yogurt and over about half an hour abandoned about a cup of clear whey, leaving a nice thick creamy yogurt in the muslin. I did this three times, transferring the finished strained yogurt into old saved yogurt containers. The kids took this to lunch and ate it for snacks, and we went through 2+ quarts in maybe a week. I would put some of the yogurt into one of those little cup tupperware things and drizzle some honey or maple syrup or even chocolate sauce over it. I bet apple butter would be yummy too.
The last of the unstrained yogurt (1 gallon=4 quarts) I put in the muslin/strainer over the pyrex again, but this time since it was time to go to work I put it all into the fridge and let it drain for 6 hours or so. By the time I got home it had given up just over 2 cups of whey, and was honestly "yogurt cheese," a thick stuff about the consistency of cream cheese. I've made dip with it, or used it as a mayonnaise substitute on sandwiches. Good stuff.
Cost Analysis: Okay, a quart of organic yogurt at Trader Joe's costs about $3. To make this, I needed a gallon of organic milk ($6--obviously WAY cheaper if you get conventional), a cup of regular plain yogurt ($1-ish, but once you've made it once you can keep using the starter for subsequent batches), and the powdered milk (hard to gauge, since I bought a giant box ages ago that I just keep around). So, assuming I'd've gotten about 3 quarts of plain yogurt out of this, that comes to about $2 savings, which isn't much. Again, using conventional milk and yogurt starter would drop the cost of making my own dramatically. Plus...well, it's sort of fun.
I'm told that one can use instant gelatin in the milk to help it set a bit more, though I haven't tried it. And apparently when the fruit-on-the-bottom yogurts get made, they actually put the fruit in first, then the infected milk, and let it incubate right there over the fruit, so that's how it keeps its nice still gelatin texture in the commercial brands. That's also, I presume, why the "yogurt makers" you buy use all the little cups instead of doing one big Vat of yogurt like the crockpot does.
So...bon appetit! It's fun! And healthy! And reduces your footprint by not going through (as I do) 2 plastic quart containers every week!