Sunday, January 24, 2010

Making Yogurt by the Quart

Ah, yogurt!

I was never a huge fan of it before. There were a few brands and flavors that weren't bad as a snack. Lemon was my favorite, but I'd try others now and then. Overall, though, it was just okay.

Then I discovered Fage yogurt. Now, that stuff was good. I liked it plain, and I liked it with the addition of my own fruit. And particularly with bananas.

Then I decided that it might be better to make my own yogurt. I read about it, and it didn't seem terribly complicated. Yogurt, after all, it just milk that's gone bad in a good way. Just like cheese.

After seeing an episode about yogurt on Good Eats, I was convinced that I had to give it a try. I mean, why not? At worst, I'd ruin some milk. Not the most expensive item on my shopping list, so I decided to give it a try.

After trying a variety of methods, I've finally got the system down to a science. It goes like this:

Heat a half-gallon of milk in a saucepan to about 160 degrees. While this is well below the boiling point of about 200 degrees up here in he high land, the milk usually begins a little foaming at this temperature.

Let the milk cool to about 120 degrees. Take about a half cup of milk from the saucepan and put it into a cup. This usually lowers the temp of the milk in the cup to about 110 degrees, which is right where it needs to be. I add the starter to the milk in the cup, stir it until it's all mixed, and wait for the saucepan milk to reach 110 degress as well. Add the cup back to the saucepan, stir it to mix it up well.

First note here is that the Yogourmet starter packet says that it's for a quart of milk, but I've had no trouble using it for a half gallon. Once I goofed and mixed it into a gallon and it never set, but it's been fine with the half-gallon batches so far.

And now it's time to find a nice warm place to ferment. My first batches, I'd put the milk into quart bottles and put them in the oven set for 110 degrees. Most ovens don't go that low, but mine's got a setting used for drying (like fruits and vegetables, not your laundry) and that's what I'd use for yogurt.

I'd make the batch in the evening and let the starter sit all night in the oven, and in the morning, I'd have yogurt. Or I'd start it earlier in the day and have yogurt by evening. It worked fine, unless I had other plans for the oven.

After some reading I found out that a lot of people got good results just by insulating the yogurt really well, wrapping it in towels and putting it into a cooler. I decided to go a tad more commercial and I bought a device that's basically a plastic food-grade bucket inserted into a styrofoam shell. It takes less space than a cooler, and it's the perfect size for half-gallon batches of yogurt.

So now, I put the warm yogurt mixture into the container, slap the lid on, and let it sit all day, overnight, or whatever adds up to about 8 hours. That's just about what it takes for the yogurt to set and to become as tangy as I like it to be. The longer it sits, the tangier it gets, so if you plan on making your own yogurt, you can experiment to get it exactly the way you like it.

When the time's up, I take the plastic bucket out of its styrofoam shell and pop it into the fridge until it cools. It gets a little thicker as it cools. But whatever you do, don't stir the mixture yet. Not while it's fermenting, an not yet. Just put it in the fridge and let it chill.

I also learned that not only do a prefer a thicker yogurt, but I also don't like the taste of a lot of whey. To me, the whey adds an astringent quality to the yogurt that I don't like, but that's easy to fix.

Some people add dried milk to the yogurt to help thicken it. I tried that, and I wasn't crazy about the result. I could taste a "cooked" flavor from the dried milk, and I didn't like that. Also, I'm making yogurt because I like the idea of a natural product. Adding dried milk seems a little bit counter to that goal.

To thicken the yogurt and get rid of the astringent whey taste, I strain it. There are dedicated yogurt straining devices and some people strain through paper towels or cheesecloth, but I've found that a fine-mesh strainer works really well if you follow a couple simple rules. First, don't stir the yogurt. If you do, it gets liquidy. Second, DON'T STIR THE YOGURT. Really, that's it.

Put the fine-mesh strainer on top of a bowl or whatever you want to use to catch the whey. I use a glass 2-quart measuring cup. Scoop up a couple clumps of the yogurt and put them into the strainer. Scoop up more clumps until the strainer is full. The yogurt is really loose at this point and it looks like it should run right through the strainer, but it thickens up as the whey drains and very little of the solids make it through the strainer.

My strainer holds about a quart's worth of yogurt. I put the strainer and cup in the fridge (with plastic wrap over the top so it doesn't pick up fridge flavors) along with the yogurt that didn't fit. As it drains, I put more yogurt in.

When I've got about a quart worth of whey, the yogurt is thick enough. Your mileage may vary, depending on the milk you start with, how long you let the yogurt ferment, and how thick you like it. You can reduce it a lot more and end up with something that resembles cream cheese. And I've done that. It makes a great spread or dip, and it's made from milk instead of cream if that makes you happier.

Anyway, I pour the whey into a jar (more about that later) and I put the yogurt into a storage container. Now, I take a small whisk and mix up the yogurt, so it's uniformly smooth and the thickness is even. That sounds a little strange, but the yogurt that's along the bottom and sides of the strainer is really thick and the stuff in the middle is a little thinner. So you want to mix it well to get it even. It does thin out a bit during the stirring, but it gets a little thicker again as it rests in the fridge.

Whey as a lot of uses. Some people drink it. But remember, I don't like that astringent quality. So you won't catch me making drinks out of it. But it is my secret ingredient in a lot of my breads. I use the whey instead of water in most breads, unless I'm strictly following a recipe. But otherwise, there's whey in the bread. Why not? You can buy dried whey to add to bread, so why not use what's almost free, after making the yogurt?

Funny thing is that I usually run out of that quart of whey at about the same time that I run out of the quart of yogurt. So it's all good.