Friday, July 18, 2008

How to Make Homemade Yogurt

What a boring title. What a boring topic. Sorry. Several friends have asked (including the one in the comments section of my last post) and it seemed easier for her and others to find it if I posted it here rather than in a reply comment. So, here it is, for whomever cares about such things.

Homemade yogurt is a staple in our home. We consume obscene quantities of it. My kids love it. Homemade yogurt is cheaper and healthier than the store-bought variety. It isn't difficult to make at all, but it - like any other "homemade" venture - is more difficult than picking it up at the store. It will be worth the trouble to you if your family eats it already and you want to cut the cost and the sugar and the preservatives down.

NOTE: Home-made yogurt is not kefir. Although yogurt is very healthy and beneficial to the digestive tract in its own right - and quite delicious - if you are interested in the kind of health benefits I extolled in my last post, you will need to choose kefir instead of yogurt. Kefir is also much easier to make than homemade yogurt.

Don't take that to mean that yogurt is difficult to make, however, because it isn't. But it does take a bit of prep work, and a good bit of time to sit and incubate. (Yogurt is a cultured product, like cheese, and has to incubate in a temperature-controlled environment for a certain amount of time.) You can either throw it together in the evening and let it culture in the oven overnight - which is what I do - or put it together on a day when you won't need your oven and let it brew during the day.

To get started, you will need milk, glass jars and lids, a starter yogurt from the store or from your own last batch of homemade yogurt, and sugar/vanilla if you want sweet yogurt instead of plain.

Here's how you do it: You will need clean jars and lids. (No need to sterilize - if they went through the dishwasher, straight from the cabinet will be fine.) You can use pint jars or quart jars, too, if you'd rather. I use any combination of sizes which I have clean and ready to go. Good "free" jars come from removing the labels and saving the jars and lids from Classico tomato and basil sauce or Mountain Ridge pure raw honey (both about quart size with a one-piece standard Ball lid), or Bonne Maman jellies (about cup size with a pretty red and white checked lid). Of course, you can just use Ball canning jars, too, if you want to pay for them and don't mind the two-piece lids. It helps if most of the jars you use take the same kinds of lids so that you know right away which lid goes with which jar as you're making your yogurt.

I start with a gallon of milk, which makes about 15 cups of yogurt in the end. (This lasts us not quite a week.) I use whole milk, which makes the yogurt creamier and thicker in the end, but I've used 2% as well, so I know that will work. I'm not sure about 1% or skim, but I wouldn't hesitate to try it if this is important to you. Since I've also used raw milk, or milk with added soy milk or rice milk in it, I think it is pretty tolerant of most base milks.

If you want plain yogurt, add no sugar. If you want vanilla yogurt - sweet versus plain - add however much sugar you like before you heat up the milk. (To get the same sweetness as the store-bought variety, you will have to add at least two cups of sugar to the gallon of milk. I add about 1/2 C. sugar per gallon now. This makes it slightly sweet but not at all "sicky sweet" like from the store. If you and your family like how sweet the store-bought kind tastes, you'll want to make your homemade yogurt pretty sweet at first to "win yourself over," then gradually reduce the sugar as you go. You'll barely notice if you just cut back a little each time.

Heat the milk in a large pot to just barely boiling. (Add the sugar at the beginning, if you use it, and stir to dissolve.) Once the milk comes to a light boil, remove it from the heat and let it cool down to the same temperature you'd want the liquid for making a yeast bread. (If you're not familiar with this "pretty warm but not hot" feeling with your finger, you can use a candy thermometer the first few times. You want it around 100 degrees, but it must be between 90 and 110. If it is too cold at the time you add the starter, it won't culture. If it is too hot, you'll kill the culture.) When it is this temperature, add about a tablespoon of vanilla (if you want it).

For the starter yogurt, I use some of the previous batch until such time that my kids end up eating all of it without saving me some starter. When this happens (about once a month or so), I start fresh with a store-bought starter. In order to get the best "health benefit" combination of live cultures (the friendly bacteria that turns the milk into yogurt), I start with a combination of Stoneyfield Farm (plain) and Activia (vanilla) brands. This combination contains the widest variety of beneficial intestinal flora, and seems to give the best "set up" power and balance of sweetness versus tartness. However, you can really start with any plain or vanilla (not flavored) yogurt where the container says something like, "Made with active live cultures." I take about half a jar (of the cup size) of my own yogurt, or a few tablespoons of each of the store-bought ones, and put it in a plastic mixing bowl and whisk it smooth. Then I take a measuring cup (Tupperware makes a really nice one with a detached handle that can hang on the side of the pot, but whatever is fine) and transfer some of the warm-but-not-hot milk into the just-whisked yogurt. I stir it in, and repeat until the bowl is full. I then pour that bowl of liquid back into the remaining milk in the large pot. (This process adjusts the yogurt to the temperature of the warm milk gradually, preventing a shock that could kill it. Since I don't bother to check the temperatures anymore with anything but my finger, I figure it doesn't hurt to be careful.)

Once the milk and starter are combined in this way, use the same measuring cup to transfer the mixture into your clean jars. Cap them and put them into a metal baking dish (for no other reason than to make transport easy and to keep them from tipping over in the oven) and place it into your oven with either the gas pilot light or the electric light bulb on. Close it up. (I latch it with the self-cleaning oven latch as a signal to myself and the others in my family that yogurt is culturing so we won't go by and accidentally turn off the light.) This (leaving the oven light or pilot light on) will maintain the correct 90-110 degree temperature range for culturing the yogurt. It will set up in a few hours, but I regularly leave it for twelve or more since I culture it overnight while we're sleeping. Once it is set up, transfer the jars to the refrigerator and enjoy!

Homemade yogurt is slightly less firm than store-bought yogurt. You will quickly get used to this, but if you really miss the texture of the latter, I remember reading that you can add some gelatin to the milk to make it more firm. I've never done this, so you'll have to find it in a cookbook or elsewhere online if you want to know how to do that.

If fruit-flavored yogurt is really important to you, you will have to add the fruit flavoring once the yogurt is made. You can use some sort of jelly/preserves or a liquid fruit syrup for this purpose. The more you stir the yogurt, however, the more liquid it will become, so be careful here.

If you eat a few bites from the jar and then add Welch's 100% grape juice to the jar and shake, you'll have pretty good replica of those probiotic-type drinks they sell in teeny little bottles for a fortune.

My kids' favorite way to eat this yogurt is as "yogurt and oats," which is where they add raw oats and stir it into a meusli-esque sort of blend. You can add apples, bananas, and walnuts or almonds if you want a true meusli treat.

Well, in my attempts to be super-detailed so I won't leave anything out, I'm sure I've scared most of you off and made it sound much harder than it actually is. It is a standard twice-a-week process in our home, and every member of my family (from the seven-year-old daughter to the 40-year-old husband) could do it in their sleep by now. If we can, you can!

Let me know how it goes!


Grace-n-Glory said...

well my friend, I'm am finally attempting this! I would have sooner but we ate the "starter" from the batch we made when you were here, and I kept forgetting to buy some. Hopefully I didn't kill the stuff (my finger was my thermometer) and we'll have a gallon of yogurt in the morning! Miss you guys and I'm so glad I watched you do this when you were here! It really was pretty easy!

Seth said...

I just made my first batch of homemade yogurt. When I put a spoon into it, the texture is firm. Upon lifting the spoon out of the jar the yogurt on the spoon is firm, but there seems to be a lot of thick liquid 'syrop' dripping from the bottom of the spoon, is that normal?