I've made a couple yogurt posts in the past but it has been nearly a year now where I make greek yogurt instead. David was diagnosed back then with reactive hypoglycemia, and as such he wanted to bring more snacks high in protein to school.
My friend Leann recommended using the crockpot instead of the stove, and so this recipe is the result of testing of many batches using various yogurt starts and other methods. This is MUCH faster than standing at the stove testing the temperature over and over, wondering when it will be hot enough. I've tried microwaving too, and I can't fit a gallon of milk in any of my microwave safe containers so it is pointless. Also, my microwave is super wimpy. I tested the wattage last year and it was around 500 watts.
Ingredients:
1 gallon milk
1-2 Tbsp plain yogurt with active cultures and no additives
First, I use Oikos plain greek yogurt as my starter. I tried saving bits from previous batches, but it just never worked as well as oikos for some reason. It is easy enough to just freeze it in little bits and thaw it while the milk cools, so that is what I do. Also I don't have to stress about saving yogurt from the old batch, or worrying if the old batch is TOO old because it took 3 weeks to eat. (I think I make this every 2 weeks usually.)
The yogurt ice cubes were a little bigger this time than last, but close enough. I just put in a couple tablespoons or so of starter, and less works too. I have found that works better than using a large amount as some people do.
Also, I use an entire gallon of milk. I buy 2% milk for it. This recipe is specific for my 6 quart instant pot. Leann's crockpot heats MUCH more slowly because it is insulated poorly. She said hers takes 5 hours to heat and mine takes only 90 minutes.
Step 1, ~ 5 pm: Pour gallon milk into instant pot. Cover with lid (I vent it) and put on 90 minutes crock pot low setting.
Step 2, ~6:30 pm: After 90 minutes test with instant read thermometer, and it should be 190 or more. I like to get the milk up to 190 F. I am not satisfied with 180, which is considered the minimum temperature for heating it, but I feel like 190 has worked better for me. (I used to test at 67 minutes, but for some reason that is not consistently adequate. I am baffled as to why.)
Step 3: Take lid off of instant pot and remove pot from the cooker. (You can choose to leave it in the cooker (lid off), but it will not be cool enough by 8 pm to proceed, you'll need to wait until 9:30 or 10.) Take out small dish and put yogurt starter ice cube on it. It will thaw while the milk cools.
Step 4, ~8 pm or bedtime, or whenever I happen to feel like looking: (Clearly this step is less precise...) Check temperature of milk again after removing the skin that has formed on top of the milk. Throw away the skin. Milk should be below 115.
If I were simply insulating the milk, I would care a lot more if the temperature dropped below 105. But I the yogurt function on the instant pot will heat up the milk to the proper temperature and hold it there for me. It is often 90 degrees when I check it later at night, so its no big deal if I forget about it and do it late at night just before bed.
Step 5: Use a whisk and thoroughly mix in the thawed yogurt cube. Then put lid back on. It doesn't matter if its set to vent or not, the temperature is kept around 110. Set yogurt to 11 or 12 hours, depending on my morning schedule.
Step 6, the next morning when yogurt is done: Line a large colander with 4 overlapping coffee filters (4 is adequate for mine). Pour off what whey you can from the instant pot. The yogurt will be set up to a point, and it will make it easy to pour liquid off the edge. Once you have got all the liquid removed that you can, scoop the yogurt into the lined colander. Mine gets very full. I let it sit in the sink and the whey goes straight down the drain. If you have a use for the whey, you can set up a collection system. There are plenty or uses for it when making fermented foods.
If I can't get it all in, I'll add the rest after 30-60 minutes, or whenever I remember. I let it strain for about 2.5-3 hours.
Step 7: Then I scoop it into a 2 quart size tupperware, stir it, and put it in the fridge. Sometimes the tupperware is too full to close so I may need a small second container. I love using coffee filters because the yogurt peels right of of it and then you can throw away the filters. I have tried using a cheesecloth and it was irritating and just made more laundry.
So that is how I make yogurt. David takes it to school in little 4 oz containers I got for him. The kids will eat it plain sometimes but like it best with honey drizzled on top.
It would cost >$10 for 2 quarts of store bought low fat greek yogurt. This makes the same amount and is the price of a gallon of milk. Plus the store I shop now (Aldi) only has fat free greek yogurt, which I object to purchasing as nobody likes it, and it is still far cheaper to make it at home. It is really not much effort at all, you just have to be around in the morning to strain the yogurt. If I worked out of the home I would just make it on a friday or saturday night.
