I am addicted to full-fat Greek yogurt, but it’s not available in my location. And even if it were, it’d probably cost a small fortune. The fat-free Greek yogurt is expensive enough, at about $6.00 a container at Costco. Fat-free is good but doesn’t satisfy that dessert craving for me like the Greek yogurt made from whole milk.
So I researched it a few months ago and learned how to make it in my Crockpot. This worked great in the summer and I was thrilled with the results. You just heat 4 cups milk in the Crockpot to nearly boiling, then cool to lukewarm, add a couple tablespoons of fresh yogurt, then wrap a blanket around the Crockpot and let set for 8 – 12 hours. Refrigerate for a few hours, and you’ve got regular plain yogurt. If you want Greek yogurt (yes yes!) then strain through a cheesecloth or light dish towel (I use a cloth diaper).
But when the weather cooled down my yogurt wasn’t setting up, even though I followed the exact same procedure. I tried leaving it in longer, using more yogurt as starter, but the results were still unsatisfactory. The yogurt was slimy and slippery, and the whey didn’t separate as well as it had before.
Back to Google I went, where I learned that slippery or slimy yogurt is a result of not being warm enough during the culture time. The slight change in house temperature from summer to fall had made the difference. I also learned that yogurt can develop better in a 100 degree oven than in a crockpot. Those little yogurt bacteria must have a consistently warm temperature to do their proper job!
Once I tried it in the oven I was hooked. In fact, I took my batch of slimy yogurt from the day before and set it in the 100 degree oven. It set up within just a few hours, and strained beautifully in no time.
I no longer heat the milk in the Crockpot or use it at all for the yogurt process. The milk can be heated rapidly in a microwave– no need to boil, but get it to almost boiling, about ten minutes for five cups in a glass measuring jar. Remove and set on the counter until milk is room temperature. Stir in one or two tablespoons of plain yogurt (can use from a previous batch or store-bought, as long as it has live cultures). Cover container with tea towel and set in 100 degree oven overnight. Refrigerate a few hours and then strain if you want really thick Greek yogurt.
How to strain: Place tea towel inside a strainer, place over a bowl. Pour yogurt into strainer. Whey will quickly leak through into bowl beneath. I leave it in the refrigerator and pour off whey as it collects, turning the yogurt around to get as much whey off as possible. (I love my yogurt super thick.)
The whey has sugar and protein and can be used for making bread, pancakes, biscuits, etc in place of milk or water.
I like to keep my finished yogurt in a Fage container, just to keep it official. Six cups of milk reduces down by more than half after straining, makes about 2 1/2 cups of yogurt.