Homemade Yogurt, anyone?

One thing I noticed last time I traveled in Central America was the lack of availability of some things that I eat regularly. One general category of lacking items was fat-free dairy. Especially fat-free yogurt, which I eat regularly. It might be available, but in the huge Paiz/Walmart I was in, I was pretty shocked that there was none. Nothing. Nada. I opted for some low-fat variety, but it was disappointing.

Hmmm...I don't really want to switch to eating full-fat or even low-fat yogurt, so lucky for my fat-free dairy habit, yogurt is super-easy to make! I've done it already on a couple of occasions, and our entire household is convinced that the homemade stuff is better than the store-bought. Look at this yumminess:

Here's what you need:
1/2 gallon of milk (I'm using fat-free, but use whatever you want)
1/2 cup yogurt w/ active cultures (this is your starter, can be homemade or store-bought)
cooking thermometer (might be optional)

Here's the super-easy (but not quick) process:
Heat the milk to 180 degrees (almost boiling), then let it cool to 115. Add in the starter, wrap in a towel, and set in a warm spot (in the oven with the light on, or on the counter if it's a pleasantly warm day and you don't have AC) for about 8 hours. Unwrap, and YUM! Serve alone, with fruit, or in anything you choose. We like to make a fruit/yogurt/granola parfait, kind of like this.

Some additional notes: For me, the thermometer is the easiest way to go. I want the milk to get hot enough to kill anything I don't want living in there (that's the 180 part), but I don't want it to be too hot to kill my starter (that's the cooling to 115 part). Some people can do this without the thermometer, but every time I've tried I haven't made any yogurt. But if you have a crockpot, and a house that's not too cold, I understand that you can heat the milk in the crockpot on low for about 2.5 hours, turn the crock off, and let it sit for about 3 hours. Then you can just wrap the crock and you are ready for incubation. If you try it without a thermometer and it works, lemme know! We used the crockpot, but also the thermometer.

A final note that a dear friend of mine in Guatemala used to just make hers by testing the temp on her arm like you do a baby bottle. I'm just not that confident. But perhaps the lesson to be learned from that is that yogurt-making is *not* an exact science! If the milk reaches close to boiling, it's probably good, and the range at which the culture will grow is not tiny (I've read 105-120, but have not experimented with that).