I made homemade yogurt a couple of weeks ago. I have been wanting to try making it for a really long time. I even had a yogurt maker on my Christmas list last year. I didn't get it, so I am trying out some different methods using appliances and other items I already have. I decided to try making yogurt in the crockpot first. It sounded very easy - too easy, really. So I gave it a go. I followed the recipe/method on A Year of Slow Cooking. It was as easy as it sounded. It is time consuming, but it involves very little active time. Unfortunately, my batch didn't turn out as thick as I'd like. I know homemade yogurt is often thinner than the store-bought stuff, but this was way too thin... it was thicker than milk, but much thinner than yogurt... it was like buttermilk. It had a good flavor, though, so I saved it (some in the fridge and froze some) and will be using it like buttermilk. After doing some reading after-the-fact, I think my heating/cooling/incubating was just off. I've since read that many people have found that turning the crock on low for 10 minutes or so every hour or two during the incubation time will help keep it warm enough so it thickens up better. Maybe I'll give that a try sometime. Anyway, I wanted to post this method, even though it was sort of a flop, for future reference if I ever do try it again.
We eat a lot of yogurt and the cost savings of making your own is just too huge for me not to try it again. A quart of homemade costs less than half of a quart of organic yogurt at the store. So I wanted to try again... so I decided to try the cooler method the day after I tried the crockpot method. I'll post again soon with my second attempt (which worked very well, by the way).
Yogurt in the Crockpot
8 cups (half-gallon) of whole milk, pasteurized and homogenized is fine, but do NOT use ultra-pasteurized (I used pasteurized, non-homogenized milk)
1/2 cup store-bought natural, live/active culture plain yogurt (I used Stoneyfield Farms Organic Cream Top Plain)
frozen/fresh fruit for flavoring (optional)
thick bath towel
This takes a while. Make your yogurt on a weekend day when you are home to monitor. I used a 4 quart crockpot.
Plug in your crockpot and turn to low. Add an entire half gallon of milk. Cover and cook on low for 2 1/2 hours.
Unplug your crockpot. Leave the cover on, and let it sit for 3 hours.
When 3 hours have passed, scoop out 2 cups of the warmish milk and put it in a bowl. Whisk in 1/2 cup of store-bought live/active culture yogurt. Then dump the bowl contents back into the crockpot. Stir to combine.
Put the lid back on your crockpot. Keep it unplugged, and wrap a heavy bath towel all the way around the crock for insulation.
Go to bed, or let it sit for 8 hours.
In the morning, the yogurt will have thickened---it's not as thick as store-bought yogurt, but has the consistency of low-fat plain yogurt.
You can blend in batches with your favorite fruit. When you blend in the fruit, bubbles will form and might bother you. They aren't a big deal, and will settle eventually.
Chill in a plastic container(s) in the refrigerator. Your fresh yogurt will last 7-10 days. Save 1/2 cup as a starter to make a new batch.