I don't think most people realize this, but butter isn't 100% fat. Really! While we're at it, neither is margarine. However, shortening is 100% fat. But this post isn't about margarine or shortening. It's not even about butter. It's about butterfat. I present for you: The Chart.
Dairy Item Percentage
Clarified Butter 100%
European Style Butter 82 to 83%
Whole American Butter About 80%
Heavy Cream At least 36%
Whipping Cream 30 to 36%
Medium Whipping Cream 30 to 36%
Light Whipping Cream 30 to 36%
Light Cream 18 to 30%
Half & Half 10.5 to 18%
Sweetened Condensed Milk 9% and 40% additional sugar
Evaporated Milk 8% and 50% less water
Whole Milk 4%
Low Fat Milk 0.5% to 2%
Skim Milk less than 0.5%
Powdered Milk 0%
As you can see, this shows the percentages of butterfat in several common dairy products. You may remember some of these percentages from my clarified butter tutorial. Knowing the percentages of various dairy products can help you cheat with some recipes, and hack others. But you really do need to know what you're doing, and how you're doing it. I'll get to that in a moment.
Powdered milk has managed to have had the water and fat removed, leaving you with little more than protein. In contrast, properly clarified butter is all fat, all the time. That's because you've managed to seperate the three basic components into layers, and then you've skimmed off the protein and dumped out the water, leaving you with nothing but the butterfat. This doesn't mean that it's exactly the same as shortening. Clarified butter can still go rancid, and should be refrigerated. Shortening has been processed and refined so that it can, and should be stored at room tempurature.
In general, the more fat a dairy product has, the better of a chance it has to whip up and incorporate air. In fact, you're not going to have much luck trying to whip anything with less than 30% butterfat. Also, the colder it is, the more easily it will whip. This is in contrast to egg whites, which prefer warmer tempuratures to whip, and will not whip at all if there is any fat present. It's a strange world that we live in.
The more you whip a dairy product, the more the fat globules will want to stick together. If you whip it enough, it's called churning, and it will cause so much fat to stick together that it starts to squeeze out water that was previously mixed in with it. It won't get rid of all of the water, but it will get rid of most of it, leaving you with what we call plain old "butter". The water that becomes seperated is called buttermilk, but it's not the same thing as the buttermilk that we buy in the store. Modern day buttermilk (aka "cultured buttermilk")is made using an entirely different process, which produces a slightly acidic milk that is popular in several cooking and baking applications, largely because of the acid.
The problem is with butter, all that whipping and churning can't be undone once it's done. You'll have little, if any luck melting down butter, mixing it with water, letting it cool, and then trying to whip it like regular old heavy cream. It just won't work. Anyone that would want to do that anyway should probably get their head examined. Or should they?
So long as you're not trying to whip it, there actually are other applications for such a thing. But you wouldn't just use water. Oh, no. You would want to use a more flavorful liquid, such as a fruit puree or even just a plain old fruit juice. Here's the way I figure it. Heavy cream is at least 36% butterfat, right? But the good stuff always has more. Not to endorse anyone, but the brand of heavy cream currently sold at CostCo is guaranteed to have at least 40% butterfat. I know several professional bakers that prefer to get their cream from CostCo for this very reason. Anyway, so we're shooting for around 36-40% butterfat. Whole American butter is somewhere around 80% butterfat. So if we mix together equal parts whole butter and, say, raspberry puree, then we'll come up with a raspberry-flavored cream that is about 40% butterfat. And since we're not planning on whipping it, who says we can't use it instead of regular cream to make a chocolate raspberry ganache? In fact, I have used this very same concept in certain desserts, and have had marvelous success with it.
What else can you do once you know the percentages? Well, let's take half & half as an example. What is half & half? It's half cream, half milk. I have a lot of ice cream recipes that call for part cream, part half & half. One day I wanted to make ice cream, but I was out of cream and only had half & half. What to do? Well, since it was going to be heated anyway, I did the math and upped the amount of half & half, and then added butter to make up the difference. My ice cream worked out perfectly. And you know, isn't it this kind of hacking that gave us things like half and half in the first place?
So now you know a little bit about hacking dairy products. Try experimenting with a recipe sometime. If it calls for milk, maybe you can get away with using a flavorful liquid and a pat of butter instead. If it calls for cream, maybe you can get away with equal parts butter and flavorful liquid. Hopefully this knowledge opens a few doors in your culinary world, as it did for me.