Straining yogurt/photos by Donna Turner Ruhlman

Most weekday mornings I eat a bowl of homemade granola with a big dollop of homemade yogurt on top.  It’s hard to get over the amount of money you pay for granola at the store. Also, I find most granola too loaded with sugar; I don’t like it as sweet as it invariably is (here’s my strawberry-banana granola recipe). Yogurt is the same, both the quality and the cost make the home-prepared better and less expensive than what you can buy at the grocery store. Also, I want to make sure it’s got plenty of vigorous, gut-healthy bacteria.

I make a batch of yogurt about once every three weeks or so, using a spoonful of the previous batch to inoculate the fresh whole milk.

I usually make regular yogurt because I like the whey with the yogurt curds. But sometimes I want a thick creamy dense yogurt, usually referred to as Greek yogurt. Though I once made the Greek-style yogurt because we had a lot of milk right before a trip so I made the Greek style yogurt to preserve the milk (the reduced water content makes it more long-lasting).  See below slideshow for Greek-style yogurt pix.

You won’t always have a culture on hand, and will need to buy some to start your own. I recently used some Fage Greek yogurt. Read the ingredients list and make sure what you buy has an active culture.  Or you can also look for yogurt starter cultures.

Key points in making yogurt:

  • I’ve found the key to a solid, flavorful yogurt is to ferment it at about 104˚ F/40˚centigrade for 18 to 24 hours. I’m lucky to have a Sous Vide Supreme, which is perfect for this. But if you don’t, you can put your container in a pot of water and simply warm it up every now and then. I’ve also heated my oven to warm and stuck it in there. And in the summer I leave it in the sun all day.
  • An important step in ensuring a solid texture is heating the milk, which denatures the proteins and so helps the yogurt to set solidly.  Remember to let the yogurt cool after you bring it to a simmer.  Adding the culture to hot milk will kill the bacteria.
  • You can use 2% milk if you wish.  I prefer whole milk, but both will work.
  • Yogurt should keep for a month in the refrigerator.

Homemade yogurt

  • 3 or 4 cups/.750 to 1 liters milk
  • 1 tablespooon/15 grams yogurt with active bacteria, or yogurt start
  1. In a sauce pan over high heat, bring the milk to a just to a simmer, then remove it from the heat and allow it to cool to 110˚F/43˚ C or below.
  2. In a glass or other non-reactive container (I use a 4-cup Pyrex measuring cup), combine the milk with the yogurt culture, stirring until the culture is completely incorporated into the milk.
  3. Cover with plastic wrap, and keep warm, ideally 104˚ F/40˚ C, for 18 to 24 hours (see post for suggestions on ways to do this), then refrigerate.
  4. For Greek yogurt, strain through an All-Strain cloth or cheesecloth for 8 to 12 hours.

Your yield should be slightly less than the amount of milk you began with.


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© 2011 Michael Ruhlman. Photo © 2011 Donna Turner-Ruhlman. All rights reserved.