By Ed Bruske
aka The Slow Cook
I'm always looking for ways to simpifly our yogurt making process. We make a quart each week with milk and cream we get delivered from our grassfed dairy, South Mountain Creamery. Until recently, I used a fairly rigorous process of bringing a mix of "creamtop" (unhomegenized) milk and heavy cream to 200 degrees on the stove top, then lowering the heat on the stove and keeping the milk at that temperature for about 20 minutes, monitoring frequently with my instant-read thermometer to make sure it didn't overheat. Then I would put the pot in a bath of cold water and quickly lower the temperature to 120 before mixing in my bacteria culture.
Well, sometimes I got distracted and the milk did overheat. Or maybe I just got tired of taking the milk's temperature all the time. And the whole water bath thing is a bit of a hassle, as well as a waste of water. In any case, I've found that my yogurt comes out just as fine--thick and creamy--if I just bring the mix to that magic 200 degrees, then turn off the stove and let the milk cool to 120 degrees on its own. Voila: I don't have to do hardly any work at all. The yogurt makes itself.
Sometimes the lazy way is also the most effective and fool-proof. The point of heating the yogurt is to make it thick. If you were thinking it's the amount of starter culture you add to the mix that thickens it, you'd be wrong. It's the heat, and the amount of time heat is applied. This binds the proteins in the milk together, resulting in thickness. So letting the temperature rise slowly, then deline slowly, gives those proteins plenty of time to do the necessary binding.
Still, this method didn't seem entirely simple enough. Is it possible to make yogurt this way if you don't have an instant-read thermomenter? Before I answer that, I would urge you to get an an instant-read thermometer if you don't have one already. It is an essential kitchen tool. That's why you see chefs walking around with one stuck in the pocket of their chef's jacket.
But, yes, I think it is possible to make yogurt without actually measuring the temperature of the milk. When the milk gets to 200 degrees, there should be a fairly thick layer of foam on top. The milk won't be bubbling--you don't want to boil it, at which point the proteins will separate. But there will be foam. Then simply turn off the burner and let the milk rest until it is just warm--not hot--to the touch. This might not be exactly 120 degrees. But the point is, bacteria are killed around 140 degrees, and the last thing you want to do is kill your starter culture when you add it to the milk. You won't get any yogurt at all if the bacteria are dead. Better to err on the cooler side.
So this is my new method for making our weekly yogurt: To make enough yogurt to fill a quart-size canning jar, first put two heaping tablespoons of last week's yogurt in a small bowl and set it aside on the kitchen counter to come up to temperature and activate the bacteria. If you don't have yogurt already, you can use any plain yogurt from the store with active cultures in it. We started with a small container of "Icelandic-style" yogurt. It was expensive, but incredibly delicious, with a distinctive tang.
Next, measure 3 cups of the best whole milk you can find, then add 3/4 cup heavy cream (the cream is optional--you can use milk only if you like.) Pour this into a heavy saucepan and heat on the lowest setting on the stove. We have an electric range, and not the typical coil burners, but those big, solid, European-style metal burners. These give off a gentle heat at the lowest setting. If you have a gas range, or if your saucepan is not so heavy, you might want to consider investing in some kind of heat deflector so that you don't scorch your milk.
Heat the milk gently to 200 degrees, as measured with an instant-read thermometer, or when there is a thick layer of foam on the milk. Turn off the heat and allow the milk to cool to 120 degrees, or to a point where it is warm--but not hot--to the touch. Use a small whisk, if you have one, to stir your reserved culture into the warm milk. Now pour the mix into a warm canning jar and place the jar in a small cooler. I usually place a couple of extra canning jars filled with hot water in the cooler as well. Set the cooler in a warm spot overnight.
The yogurt will form within a few hours. But since I restrict the number of carbohydrates I eat, I let my yogurt ferment another day at room temperature. This gives the bacteria plenty of time to convert the naturally occurring lactose in the milk into lactic acid.
Try this and see if it isn't the best yogurt you've ever tasted. You may never buy yogurt again. |
