Wait! Before you roll your eyes and say "I can't make yogurt" or "I have no yogurt maker" read over my tutorial and you will see yogurt is very easy to make without a commercial yogurt maker! I always thought it was a big deal but since I've been making my own I found out it's not that difficult. I like to make lots so when I was learning to make it I found several different recipes and took a bit of information from each of them and created my own. Because I use skim milk my yogurt isn't quite as creamy as you would get from the store but you can use whole milk if you like it creamier. As I've often said I am not a "precise" measuring kind a gal, but follow my guidelines somewhat and you'll end up with two 1 kilogram containers of very nice tasting yogurt :) And if you use skim milk it's fat free, a girls gotta keep her girlish figure, ya know.
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Step 1: Ingredients
1 1/2 cups skim milk powder
6 cups skim milk
1 cup distilled water, bottled water, or RO (reverse osmosis) water
1/3 to 2/3 cup starter (plain yogurt with active cultures)
Start with a large measuring cup, mine is 8 cups in size.
Do not use any aluminum utensils and everything must be very clean!
Step 2: Milk
Add 1 1/2 cups of skim milk powder to your measuring cup.
Then add 6 cups of skim milk. You can use 2% or whole but to keep it fat free I like using skim.
Add 1 cup of distilled water, I have an RO system but bottled water is fine. This should bring the whole thing up to roughly the 8 cup mark on your measuring cup, that is, if you have the same one as mine, if not, then wing it :) I've put less milk in and more water, it all depends on how much milk I have in the house when I make my yogurt.
Step 3: Yogurt Book
I found a Yogurt recipe book in a second hand store awhile ago, which lists the different kinds of milk you can use and the results, such as; evaporated milk, half and half, lowfat, whole milk, dry milk, nonfat. The book is very good and is called "The Complete Yogurt Cookbook" by Susan Mintz and published by Nitty Gritty Productions, the date on the book is 1978, I'm not sure if it's still in print but you might get lucky and find it the way I did. It's full of recipes, flavourings, ideas, etc.
Step 4: Microwave
Stir the mixture with a whisk so there are no lumps and all the skim milk powder is dissolved. Put in the microwave for 15 minutes on high until just boiling. I had to put it in for a total of 17 minutes.
Step 5: Cooling Down
Remove from the microwave but don't put the thermometer in right away! The whole thing will boil over! Wait a few minutes and then gently put it in. Let everything cool down to under120 degrees Fahrenheit, preferably closer to 115. This can take up to an hour. In the meantime; turn on your dehydrator and warm up your containers you are going to use. Now is a good time to get your starter ready.
Step 6: Starter
For your starter you can use any brand plain yogurt as long as it has active live cultures in it. The bummer is I cannot purchase a "small" container of plain yogurt and you use so little it's a waste sometimes when I have to buy new starter. Anyway... Try to bring it to room temperature but if you forgot to take it out of the fridge it's no big deal. Today I'm using starter from homemade yogurt I made a few weeks ago. Not the greatest because you should use the freshest you can get your hands on. If you do continue to make yogurt using your own starter you should replace it ever few weeks with new (and if you find it somewhere where they sell it in small containers you'll be sure to drop me a note, won't you?).
I have tried freezing starter to use later on but it didn't turn out too well. I bought a powdered yogurt starter and it works pretty good.
Step 7: Mixing Starter
When the mixture is cooled there will be a skin on top, gently remove it and discard or, for a great laugh, throw it out to the chickens and watch them fly around the yard trying to hoard it to themselves!
I use a canning jar for mixing and add 1/3 to 2/3 cup of starter to the jar. I then add some of the cooled down skim milk mixture, about a cup or so. Stir it up fairly good so there are no lumps. Then dump the whole thing back into the main mixture. Stir well but not overly aggressive.
Step 8: Place Lids
This recipe makes two 1 kg containers. I place the lids on the containers and set them in the dehydrator. If you leave the lids off you will end up with a heavy skin on top! Of course I didn't know that the first time I used my dehydrator for yogurt but, as I always say, "lesson learned."
Step 9: Timer
Because I do not have a built in thermometer on my dehydrator I use one of those indoor/outdoor ones with the cord strung through and the button near the yogurt. I try to maintain a constant temperature between 110 and 115 degrees. I also set a count-up timer because I've had yogurt set in as little as two hours and I like to check it often. I used to think I had to leave it in overnight but found out the longer you leave it in the stronger tasting it becomes, and I wasn't looking for a strong tasting yogurt. Usually about 4 hours, give or take, is enough for me. This batch was done in exactly 3 hours and 37 minutes.
Step 10: Checking Your Yogurt
To check your yogurt, simply lift the lid off and tilt it, ever so gently, sideways. When it starts to set it will be a bit jelled, the longer you leave it the firmer it will be, but beware of leaving it too long because it will get a stronger flavour the longer it incubates. When it gets almost to the point of where you like it, take it out, place it in the fridge and it will continue to firm up a bit more as it cools down.
I've flavoured the mixture before letting it incubate using everything from jam to instant coffee with Splenda (artificial sweetener) added. But I let it incubate plain now and add the flavourings after it's done, only because I need plain starter for my next batch. The kids love it with a few dollops of jam mixed in. I like to eat it plain, and I even like it hot straight from the dehydrator! Another great way to eat it is to let it drain overnight in a colander lined with cheesecloth. The next morning you will have very firm yogurt "cheese." Add onion soup mix and seasonings and you've got a great dip for chips or veggies. Add jam and you have a nice dip for fruit. You can use yogurt in place of sour cream too. We often put it on our potatoes and I've also baked with it. Google yogurt recipes and you'll come up with a ton of them.
If you don't have a dehydrator for incubating there are numerous other ways to do it, Hillbilly Housewife has a few suggestions as well as Fias Co Farm, two places I first used when I started making my own yogurt. I've heard of using an electric frying pan, woodstove, thermos, or Styrofoam ice chest, there's bound to be something you have! Let me know how your yogurt turns out!
I was reading through my Yogurt book and besides all the things I mentioned above for incubating yogurt you can use your oven (gas or electric) as well. Instructions are as follows:
"Yogurt can be incubated very successfully by the warmth of the pilot light in a gas oven. Place the covered container of prepared milk on a rack in the top half of the oven. On a rack directly below, place a large, flat baking pan filled with boiling water. This will help to sustain the heat of the milk at the beginning of the incubation process. In an electric oven, turn the thermostat to the lowest possible setting. If the oven is still too hot, leave the door ajar while incubating the yogurt. Oven incubation is the easiest method to use for making large quantities of yogurt." (I think this last statement rings a bit false as I can fit quite a bit of yogurt in my dehydrator!)