Sour Cream, Crema, Crème Fraîche: What's the Difference?
Sour cream, crema, and crème fraîche: these three dairy products are often used to add a cool lusciousness and body to foods like potatoes, salads, and nachos. But while all three products are made the same way—by adding friendly bacteria to heavy cream—they’re all technically different ingredients.
Sour cream has a fat content of about 20 percent and a pronounced acidic flavor, which makes it a nice mix-in for any dish that could benefit from a little tang. (Like buttermilk, it also works nicely in marinades.) Sometimes you’ll find it stabilized with additives like gelatin, vegetable enzymes, or animal enzymes to help thicken the product. But because it has a relatively low fat content and high protein content, it’s less stable under heat and tends to curdle easily. For this reason, it’s best used in cold preparations or added to the top of a hot dish (like chili) at the very end.
Crème fraîche, on the other hand, has a richer, more buttery quality to it than its sister, sour cream. This is reflected in the product’s high fat content — around 30 percent — which naturally gives it body and thickness. (It doesn’t tend to have any added thickeners or stabilizers.) Because it has more fat and less protein, it can work in soups and simmering sauces (take beef stroganoff, for instance); it will melt easily, but won’t curdle. You can make it yourself without much effort.
Then there’s the matter of Mexican crema, which is runnier, thinner, and slightly sweeter than both crème fraîche and sour cream. In Latin cuisine, there are a number of different kinds of cultured creams, like the sour, runnier jocoque and the thicker crema Salvadoreña, but the most common one you’ll find is the sweet, tangy crema Mexicana. It’s available at Mexican grocers, but if you can’t track it down, it’s easy enough to make yourself with heavy cream and buttermilk (or, in a pinch, a blend of sour cream and heavy cream).
All three are popular on top of spicy foods like nachos and tacos, so unless you’re heating them through or thickness of the cream is a real issue, they can often be used interchangeably.