"Wait! What? Did I read that right?" you ask. Yes, you did. If you have milk, a few glass containers and a microwave, you can make yogurt at home in as little as a few hours!
This is a process my wife Kat learned not long ago. An advocate of what is called "Simple Living" by a growing number of people, she is always looking for ways to create for ourselves what most folks run to the store and spend what is often way too much money to purchase. Yogurt is one of those things.
What is yogurt, really, besides curdled milk? Add some fruit or jam and stir. "But I just don't have the time!" people say. "It takes so much time to do these things!" Does it really? I'm making yogurt right now while I write this. Or rather, the yogurt is making itself!
Here is a list of what you'll need to make 2 quarts of yogurt.
2 quart sized mason jars with tight fitting lids
a large microwave safe bowl (I use a 2-qt. Corningware dish with a lid)
a quick read thermometer
2 quarts of milk
6 T plain yogurt with active/live cultures
6 T powdered milk (optional - helps to make the yogurt firmer)
The cultures in the plain yogurt act as the starter. Begin by filling the mason jars to the 'shoulders' of the jar, leaving a good 1" to 1-1/2" space at the top of the jar. Microwave the milk on high heat for 3 minutes, then stir and take the milks temperature. You want the milk to get to 185°, but don't go too fast! Gently heating the milk here is best! After the first 3 minutes, heat it for another 3. When the milk reaches around 115-120°, reduce the heating time to 2 minutes. As you get closer to 185°, reduce the time in the microwave to 1 minute between stirs.
Once the milk reaches 185°, take the jars out of the microwave and set them in a cool place. The milk should be allowed to rest and cool to 115°. In heating the milk, you have killed any airborne yeasts and bacteria that may have gotten to the milk. This also helps to denature the yogurt which prevents clumping.
After the milk has cooled down to 115°, stir in the yogurt and powdered milk (if you choose to use it), 3 T of each per quart of milk. Fill your large microwave safe bowl about 2/3 to 3/4 full of water and microwave it on high until it nears the boiling point. Gently rest the flat part of the mason lid on each jar but do not secure it down with the ring. You do not want the jars to be tightly sealed, you are only trying to keep moisture from dripping in. Leaving the large bowl of water in the microwave, place the covered jars beside it and close the microwave door. Your microwave is well insulated and will hold the heat in. You want the milk to remain between 90° and 110° for about 8-12 hours. Every couple of hours or so, check the temperature of the water and, if you need to, reheat it (just don't forget to take the yogurt out of the microwave while you reheat the water!). If your yogurt drops below 90°, don't panic! It will be fine, it'll just take longer to make! What you absolutely DO NOT want is for it to get warmer that 110-115°! Do that and you will kill the yogurt cultures! After 6 hours or so you will notice that your yogurt has set. Taste it to check its fermentation. It will get tangier as it sits. I like a tangy yogurt so I usually let it sit longer.
And there you have it! Start your yogurt at night and you'll have a fresh, tasty breakfast waiting for you in the morning! The fact that the yogurt takes just as long to make as most of us sleep makes this a perfect overnight activity!
"Hold on a sec," I hear someone saying, "what about botulism?" First of all, botulism has a hard time growing in the highly acidic environment of things like salami, sauerkraut and yogurt. The lactic acid produced by the yogurt cultures prohibit the growth of bad bacteria. But caution never hurt anyone. Make sure your equipment is clean and sterile, making sure to completely clean your microwave before and after use. Also, remember that you are making plain yogurt - do not add fruit or other flavorings until after the yogurt is finished and is about to be served! More information can be found at this website.