I got this recipe from Paula Wolfert's The Cooking of the Eastern Mediterranean, which has proven to be quite a book on more than one occasion.
I am the kind of cook that doesn't know what I'm doing most of the time: I get by just by using the exact same processes that I've used before (based on both real and imagined results), and simply by following recipes to the T. Here's how to make yogurt exactly the way that both Paula Wolfert and I have made it- it does, in fact, turn out very nicely.
To make good yogurt start with good ingredients:
1/2 gallon milk
3 or 4 heaping tablespoons of yogurt
Sm. pinch of salt
Other items you'll need:
Glass jars
Cheesecloth
Strainer
Optional: thermometer
Yogurt
You will need a yogurt that contains live cultures. Look for brands of yogurt with Lactobacillus bulgaricus in the ingredients list. I myself chose Hawthorne Valley Farm yogurt, available at the Greenmarket or at most local health food stores. It is really good stuff.
Milk
Also choose good milk. Y'know: organic, tasty.
First, bring milk to boil in a heavy-bottomed pot. Simmer for 2 minutes (this pasteurizes or re-pasteurizes the milk).
Allow the milk to cool until it reaches 110 degrees. If you don't have a thermometer, aim for warm milk (imagine the temperature you would like best if you were a bacteria).
In a small bowl, gradually mix 3 heaping tablespoons of the yogurt with a little bit of warm milk. Then slowly add this mixture to the large pot of milk.
Pour yogurt concoction into glass containers. I used regular size Ball canning jars (4).
Cover jars with plastic wrap, and wrap with towels. Put the jars in the warmest part of the kitchen for 6 to 24 hours, or until the yogurt has jelled.
Note: The length of time it takes the yogurt to jell is directly related to the temperature of yogurt during this period. The ideal temperature is somewhere between 100 degrees and 110 degrees (for example a baking day would be the perfect time to ferment the yogurt). If the yogurt stays at the proper temperature, it should jell within 6 hours. If you let the yogurt ferment at a lower temperature the yogurt will not jell as quickly. The longer it takes to jell the tarter the yogurt.
After yogurt jells, let it chill overnight with the jar lids on loosely. In the morning, it will be ready to eat!
Straining yogurt
To make a thicker yogurt: lightly salt, and then strain with cheesecloth in strainer for 20 min to 24 hours, depending on the desired consistency. I would recommend straining the yogurt for at least 1 hour. For a thick, sour cream-like consistency, strain for a long time (max 24 hours).
Save the whey and drink it. It tastes pretty gross but is reputed to be good for your kidneys (says Ms. Wolfert).
Final words
For all you baristas out there, you know this already: milk is gross, especially hot milk. Don't you worry. Just forage on ahead, yogurt makers! -Lu
