I am all for improvisation when cooking, but there are some kitchen rules that must be obeyed to avoid disastrous results. Don't overcook shrimp is one worth noting. Don't ever put knives in a sinkful of water (you might forget, and cut yourself) is another.
There are also a few important dos and don'ts regarding cooking with dairy products.
Some dairy products (milk, heavy cream, sour cream, creme fraiche, and yogurt.) react in surprisingly different ways to high heat. And unless you know how the dairy you're using will react to heat, you may be in for a rude surprise when you whisk it into a dish. Whether using a rich dairy ingredient to thicken a soup or create a luscious sauce, here's what you should know about heating various types of dairy on the stovetop or microwave.
Heavy Cream
This is an easy one, because the fat content of heavy cream is so high that you can heat it, boil it, and even reduce it to your heart's content. It won't break, or separate. But do be aware that high acid additions — like citrus, wine, or tomatoes for example — might curdle it a bit. Not enough to ruin it… but a little.
Sour Cream
Surprising, to me anyway, was my discovery that sour cream has a fat content sufficiently lower than heavy cream, such that boiling it will cause problems. So my recommendation is to add it at the end of cooking your dish, on low heat, and just keep it on the flame long enough to heat it. That way you're totally safe. Never boil.
Creme Fraiche
Creme fraiche has a high-fat content, and therefore, you can use high heat without fear. And, once you start experimenting with creme fraiche, you may discover that its fuller and deeper flavor starts edging sour cream out of your list of favorites.
Yogurt
As I'm sure you're aware, even full-fat yogurt is relatively low in fat. Therefore, like sour cream, I'd advise adding it at the last minute after reducing the heat and allowing the dish to cool down for a few minutes. Otherwise, welcome to the separation city.
Milk
No matter the percentage you're using, the same issues that sour cream and yogurt face apply to milk. Thus, you should follow the same precautions when heating it. Here are some tips if you want to scald the milk with precision.
That said, I wanted to see if any of the above rules could be broken. And I discovered that there are a few ways around them.
Other Tricks for Preventing Dairy Disasters
- A little flour will help stabilize and prevent curdling. Therefore, any roux-based dish should be pretty safe to incorporate dairy into.
- Tempering the sour cream or yogurt with a little of the warm sauce or broth before adding it to the dish will also help (but you still can't boil).
I hope these guidelines help. Just remember: very high-fat content paired with high heat is fine. Meanwhile, for ingredients with a lower fat content: barely heat, go slowly, maybe add a little flour, and never boil.
