|Last time I used a recipe that, well... didn't work out. Part of the problem is that I didn't know what to expect, so when I discovered my totally-not-yogurt result (a.k.a. spoiled milk), I wasn't sure if I had succeeded or failed. After all, the recipe said the resulting yogurt might be runny and lumpy. Was my runny and lumpy result yogurt? Turns out it wasn't.
One of two things happened the first time around. Either the yogurt I used to introduce the live cultures into my milk did not have any live cultures OR I did not keep my yogurt-to-be at the right temperatures so that the live cultures couldn't do their job. Either way, it was a total failure. So here's what I did this time.
Ingredients: Yogurt starter + milk
Equipment: Saucepan, thermometer, ladle, mason jars.
1. Preheat the oven to 200F. You can also just use the warm oven that results from baking something else. In my case, I had been making jam and that required heating the jars to 200F in the oven before filling them with jam so the oven was already heated.
2. Heat 1 quart + 1 cup of milk to 180F. You can use whatever quantity you want but here's my rationale. Lately when I buy a half gallon of milk (2 quarts), it goes bad before I can use it all. So if I use about half of it for yogurt, then I can drink the rest in my coffee before it goes bad. I made 1 quart to eat as yogurt, and 1 cup to use as yogurt starter in the NEXT batch of yogurt.
3. Cool the milk to 108F-112F. Just let it sit and stir it every so often.
4. Mix in the yogurt starter. You can use yogurt instead of yogurt starter if you want.
5. Ladle the yogurt into mason jars. Do NOT put the lids on.
6. Turn the oven off.
7. Put the uncovered mason jars in the oven. Check the clock as you do this. Your jars need to stay in the oven for 4 hours.
8. Heat up 1 quart of water in a kettle. It doesn't have to be boiling. You're not making tea. But heat it to hotter than 112F.
9. Fill an empty mason jar with the hot water. You can put the lid on this one. (As noted in the comments, don't tighten the lid too much because it will be VERY hard to get off once the water cools.)
10. Put your jar of hot water in the oven with your yogurt-to-be. Once the temp of the oven starts to go down, your hot water will keep things nice and toasty.
11. And... that's it! You're done. In four hours, you've got yogurt. At the halfway point, I turned the oven on again (I set it to 200F) and let it heat up for a few minutes. Then I turned it off. You REALLY don't want to heat it too much and kill your cultures, but liquids heat up very slowly and the air in your oven does not conduct heat very quickly. So the odds are on your side. Still, the guesswork involved here makes me think that perhaps I should invest in a yogurt maker that will keep the temp constant for me.
12. After four hours, put the yogurt in the fridge. At this point, I put the lids on my mason jars.
And the result:
That's my 1 quart jar AFTER I ate some of the yogurt. It was full when I took it out of the oven.
You know how the instructions I read the first time around warned me that my resulting yogurt might be runny and lumpy? Well, sure, this was a bit lumpier than creamy smooth store bought yogurt. But it STILL looked like yogurt. And it tasted like yogurt. I am sure I could have bothered with straining it through a cheesecloth to remove the whey if I had wanted to, but it tasted just fine as it is. It tasted like yogurt. In fact, it tasted so much like yogurt that my cat Molly (the tabby) could barely contain her excitement while I ate my first bowl of it because she knows that she gets her turn after I'm done. I guess the lesson here is: When in doubt, trust the cat.