There are a lot of foods it just doesn’t make sense to make at home. I tried making butter once: at the end of the day, I had a very messy kitchen and some very expensive butter that wasn’t any better than store-bought. Some foods, like ketchup or cola, are a matter of complexity; you’re never going to create something as well-balanced and harmonious as Heinz or Coke.
Yogurt isn’t one of those foods. It’s cheaper than buying it ready-made (in my case it costs about the same, but I buy fancy milk and strain my yogurt extra-thick). It’s ridiculously easy to make, taking less than an hour of actual work. And, most importantly, it tastes infinitely better than any commercial yogurt I’ve ever had in the U.S., including fancy yogurt from the farmer’s market.
Makes 1-2 quarts
- Two quarts whole milk
- 2-3 tbsp plain yogurt
Put both quarts of milk in a pot and heat on the stove, stirring regularly. As soon as it reaches 180 degrees, remove it from heat. This denatures the proteins, which I’ve been led to believe yields to a firmer yogurt.
From here, you need to cool the yogurt down to just below 120 degrees. Above 120 degrees, the bacteria that turn the milk into yogurt will die, and at temperatures cooler than 100 degrees they just won’t do very much. I personally use an ice water bath in the sink, but you could just let it sit a while.
Once the milk is in that magic 110-120 degree range, take 2-3 tablespoons of plain yogurt and mix with about a cup of the warm milk. Take two quart mason jars and evenly divide both the milk-yogurt mixture and the rest of the milk between them so there’s an even distribution of the yogurt culture between the two jars, then put the lids on. If you don’t have quart mason jars lying around, feel free to use whatever sized containers you’d like, so long as they can be tightly closed.
You now need to keep your yogurt at 110-120 degrees for 6-8 hours to culture. Take a large pot and heat some water to around 120 degrees, and put the mason jars inside the pot of water. You want the pot to have just enough water in it so that when the jars are inside, the water comes up to just below their lids. Put a lid on the pot, put it somewhere it won’t be disturbed, and leave it be. (If your oven has a pilot light, some people just put the jars in there instead).
I tend to check on the temperature every couple of hours and pop the entire thing on the stove for a few minutes to get the temperature back up into the 110-120 degree range if it drops below 100, but I wouldn’t worry too much about it.
The yogurt should be done when picking up one of the jars and turning it over makes it apparent that there is a single solid object inside rather than a liquid. When you’re satisfied, move the yogurt to the fridge.
For thicker, Greek-style yogurt, strain it through some cheesecloth (paper towels on top of a strainer can work in a pinch). The longer you leave it, the thicker it’ll get. I typically let it strain inside the fridge for a full 6-8 hours, which results in a quart of whey and just under a quart of luxuriously thick and creamy yogurt.
A note about fermentation
With fermented foods like yogurt, adding temperature has a similar effect to adding time. The longer or warmer your yogurt ferments, the thicker and more sour it will be. Want it less tangy? Don’t ferment it as long. Is the temperature a bit on the low end? Feel free to compensate by letting it ferment a little while longer. If you were making yogurt on a commercial scale you’d need to treat it as a precise science, sure, but when making yogurt at home I’ve found you’re better off relaxing and just going with the flow.