1. It's way cheaper
2. I know what ingredients are used
3. I like to do stuff like this!
Here's how we do it:
Take one or one half gallon of 2% milk (you can use any kind of milk, really, but 2% is our compromise). Shake it a bit if it's sat for a while. Pour the entire amount into a crock pot set on high. Cover with a lid and wait. Keep a thermometer handy and every half hour or so, stir and check the temp - it takes a couple hours to get to 180°, which is the 'magic' number for yogurt.
Once it gets to 180°, turn off the crockpot and let it sit again. You can take the lid off now if you want - it helps it to cool down faster. You can also stir it every now and then for the same reason - it cools faster. Keep the thermometer handy yet. Once the milk hits 110°, it's time to move to the next step.
Turn your oven on to 200° (or the lowest temp it will hold). Then, to the cooled milk, add your starter, which is about 1/2 cup of plain yogurt. It should be yogurt with 'live cultures' written on the container, or you can use some leftover from your last batch of homemade yogurt, which is what we do (but I'll bet if you're reading this, you most likely don't have any leftover homemade...yet...lol). You can also add some powdered milk at this time, but this is purely optional and I don't do it if I don't have any hanging around. But if you do have some and you want to add it, you can put in about 1/2 cup.
Now put the lid back on and set the lidded crockpot liner into the oven and shut the oven off. Don't forget to do this! If the oven has a light, turn it on - it will help keep the temperature nice and warm in there. Now, let this sit for about 12 hours (it can be as long as 24, but who can wait that long??) The longer it sits, the more tart and thick it will be.
After waiting, take out the crockpot and voila! you have yogurt! You can stop here, but if you have a couple more hours, it's great to make it into Greek yogurt, which is just yogurt that has been strained of the whey, and therefore, much thicker and creamier.
You'll need a strainer and some cheesecloth, or a muslin bag, which is what we use. Ours is the one that we use when we brew beer, but they're easy enough to make out of a piece of unbleached muslin sewn into a bag about 12" square or so. Put the strainer, lined with cheesecloth or the muslin bag over the edges of a bowl or pot (6-8 qt. works fine). Ladle the yogurt into the strainer/bag. If you're using a strainer, just let it sit. If you've got a bag, tie it up and hang it over the bowl to drain for about 2-4 hours. I loop the tie over a cabinet pull (see below) and just forget it for a bit.
I haven't found much use for the whey - there are websites that say you can make cheese from it, but I have not been successful at that (let me know if you are - I'd love to know the secret!). But we do have dogs, and one of them in particular (our senior, Shadow) loves to have a little whey over his kibble as an enticement to eat. Sometimes he needs a little convincing. :)
Once the yogurt has drained to a nice consistency, just transfer it from the strainer/bag to a container and refrigerate. One gallon of milk makes about 2 quarts of yummy greek yogurt and 2 quarts of whey. All for the cost of a gallon of milk! 'Whey' better than what you'd pay if you bought it at the store, and 'whey' better knowing you made it yourself!!
A hint on timing: The whole process from start to finish (greek) takes about 20 hours. It works for us to start around 6 pm. By about 10 pm or so, the milk is going into the oven for an overnight stay. And by 10 am or so, it's being strained for a few hours. Finished product is ready by early afternoon.
And as a side note, I've taught hubby how to make yogurt, so he no longer has to 'hint' to me that we are running low! :)
