Not sure what crème fraiche is or why you should care?

Consider it a relative of sour cream. Except that while both are white, thick and creamy, crème fraiche is the richer, sexier and more talented relative.

Here’s the deal. Like yogurt, sour cream and crème fraiche are dairy products produced thanks to the miracle of beneficial bacteria.

But while yogurt is made by adding those bacteria to milk, sour cream and crème fraiche are made from cream.

So what’s the difference? Sour cream is made from cream that is 20 percent fat; crème fraiche sports an even more succulent 30 percent. That may not sound like a big difference, but it matters in both taste and versatility. That extra fat turns crème fraiche into a kitchen workhorse.

But first, taste. While sour cream tastes, well, sour, crème fraiche is rich and tart. And as a byproduct of the bacteria added to produce it, crème fraiche tends to make other foods taste buttery. But unlike yogurt, crème fraiche isn’t particularly acidic (so it’s not great for marinades).

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Every week, Alex Guarnaschelli, host of Alex’s Day Off, shares with readers what she’s eating — whether it’s from the farmers’ market or fresh off the boat, she’ll have you craving everything from comfort food to seasonal produce.

As a lover of all things dairy, I especially like sour cream, yogurt, crème fraiche and buttermilk because they add “tang” to my cooking. They get their base flavor from friendly bacterial cultures that actively convert the natural sugars in milk lactic acid through fermentation. So if each of these four tangy dairy variants gets its signature acid zip the same way, what makes them different?

Sour Cream: Take cream, add those miraculous cultures, allow fermentation to partially run its course, and voila. It’s has such a thick texture, it can stand on its own. A dollop of sour cream on a baked Idaho or sweet potato is just delicious. I love adding sour cream to blue cheese dressing instead of mayonnaise. Hot blueberry pancakes topped with cold sour cream? It’s so creamy against the fruit.

Yogurt, crème fraiche and buttermilk »