Many years I have attempted yogurt and have been successful in as much as you would cook with it, but never made yogurt I could just eat straight out of the jar. Most of the time it was kinda runny and or thin. I would us it instead of buttermilk in biscuits, cornbread, etc. I bought a yogurt maker last summer, and while it is nice having one, it isn't necessary for successful yogurt making. My yogurt was still the same consistency as before. So in frustration and ready to give up I went to the internet to get the answer. So without further adieu, here is how I did it.
4 cups of milk (I have used dry; reconstituted, whole, or 2%)
1 6 oz container of store bought plain yogurt (Make sure it has active cultures. I like Dannon or Stonyfield farms. Once you make your first batch of yogurt, you can set aside some to be your culture next time and you wont have to buy any, SAVINGS!
1/3 cup of sugar (gives the bacteria something to eat)
So first of all you want to heat your milk up to 180 and keep it there for 30 min. This alters the makeup of the milk to make it more receptive to the culture. About half way thru the 30 minutes, you need to prep whatever container you are going to use. I have little 6 Oz glass jars in my yogurt maker, but a glass Mason Jar or any glass jar capable of holding 1qt yogurt; 2 pint jars work as well. Make sure these are clean and then totally submerge them in water and boil them. I boiled them about 15 min. This kills off any unseen germies that could attack the good bacteria. When the 30 minutes is up, remove the milk from the heat and let cool to 110. This won't take long. When it has cooled to the 110, add your culture. Mix it well. Wait a few minutes and mix it again just to make sure the culture is evenly distributed. Pour the mixture into your now sterilized container. If you have a yogurt maker, Kudos. Set it up and off you go. But like I said before they are not necessary. I used to take a Playmate cooler (Any cooler will work, but keep it small), fill up a couple of pint jars with very hot water and put them and the yogurt in. Then I would put hand towels all round. I once saw a lady who very shrewdly inserted a light bulb into the lid of a Styrofoam cooler and used that as a heat source. The idea is to incubate your yogurt keeping the temp above 80 degrees but not so hot that it kills the bacteria. Once it is set up, leave it for about 4 hours. Check it out and if it has set up, then refrigerate. You can let it sit for up to 8 hours, but the longer it sits the more tangy it will be. It will set up more in the fridge. Mistakes in yogurt making are still great for a substitute for buttermilk, so give it a try. It is something that is not very labor intensive. My cost analysis for this initial batch, culture included, is 32 oz for 1.49 and that is because I used a greek yogurt culture and they are more expensive. Now that I have made my yogurt and therefore my culture for the next time, my cost for 32 oz of yogurt will be .68. Compare that to the cost of a 32 oz container of yogurt on sale at the store. The cheapest I have seen is a sale price of $1.99. Even buying the more expensive yogurt for a culture still put me cheaper than store bought.
NO WHEY! GREEK YOGURT!
Big FYI here. You can make your own greek yogurt by simply straining your homemade yogurt. The whey that is drained off is a great source of protein and it also aids indigestion. You can add it to biscuits, corn bread, quick breads muffins, etc. If you are making oatmeal, put your oats in the bowl the night before with 2 TBS of Whey and the water to cook them with let it soak overnight then cook it up the next morning. A good resource for using the whey is the book " Nourishing Traditions" by Sally Fallon.
Got some cheese cloth or other type cloth that will allow you to strain off even more? Put your yogurt in the cheese cloth and hang it up over a bowl ( of course) to catch the whey. Once all the liquid has drained off you will have yogurt cheese. Use it like cream cheese. You can add fresh herbs to it and have some awesome spread.
So what are you waiting for! Go for it!