It cannot be denied that even mediocre butter is delicious: rich, creamy, soft.
But cultured butter is special. Made from cream that’s been allowed to ferment, it has a tang and buttery-cheesy flavor that makes it worth seeking out and paying more for—or making yourself.
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How Is Butter Made?
Everyone knows butter is made by churning cream. But here’s exactly what’s going on in the process:
Cream comprises about 35–40 percent fat in the form of microscopic suspended globules surrounded by watery liquid. When the cream gets agitated—churned—the fat globules slam into each other again and again. As they do, they stick together, gradually coalescing into tiny grains and then bits of fat and finally whole lumps of solid fat floating in a thin, milky, fat-free liquid. The lumps are butter, and the liquid is buttermilk.
The lumps are strained, kneaded, and pressed to create firm, spreadable butter that contains about 15 percent moisture emulsified throughout it.
What Is Cultured Butter?
Cultured butter is simply butter that starts with cream that’s been fermented.
Before refrigeration and the mechanical separation of cream, all butter was cultured butter. Fresh milk was added to a container and allowed to sit for a couple of days to let the cream portion separate naturally, its higher fat content buoying it to the top of the jug. After that happened, the cream was skimmed off and made into butter. But that unrefrigerated resting period inevitably also allowed bacteria to ferment the cream a little bit.
The bacteria turned lactose into lactic acid, imparting a pleasant tartness, and produced numerous other flavorful compounds as well, such as diacetyl, whose flavor is synonymous with butter. Modern butter has these flavors added during manufacture, because without them, the butter simply would not taste buttery.
Some butter makers, especially in Europe, add a bacterial culture to their cream instead and allow controlled fermentation to take place and flavor the butter in the same way.
Doing the same thing at home is remarkably easy. Here’s how.
How to Make Cultured Butter
You’ll need heavy cream (the higher quality, the better) and store-bought buttermilk.
In a very clean, closeable container—this can even be the carton the heavy cream comes in—combine 1 quart heavy cream with 2 tablespoons buttermilk.
How to Make Cultured Butter
For the most flavorful butter, use pasteurized, versus ultra-pasteurized, cream.
1 quart heavy cream
2 tablespoons buttermilk
- Combine cream and buttermilk in a clean, closeable container (the carton from the cream works well). Close the container, place it in a cool room-temperature spot, and leave it for 24 hours. Check it and see if it’s thick and smells wonderfully buttery. The flavor will get more tangy and funky the longer you leave it, up to a week if the temperature is cool (which slows down the bacterial action).
- When it’s gotten as tangy as you like it, put it in the fridge overnight (or longer). This allows the fat to gradually solidify.
- On the day you’re ready to make your butter, take the cream out of the fridge and let it slowly warm up to 55°F (12°C).
- Transfer the cream to a food processor, or a stand mixer with the whisk attachment, and process. You’ll see it transform into whipped cream; keep going. Over the course of 3 minutes or less in the food processor, or longer in stand mixer, the whipped cream will become grainy with bits of butter and then turn into lumps of butter splashing in liquid. (The liquid is buttermilk.) Stop the machine immediately.
- Line a fine-mesh strainer with a triple layer of cheesecloth, leaving a few inches of cloth hanging over the sides. Pour the butter mixture through your cheesecloth-lined strainer into a large bowl.
- Fill a medium mixing bowl halfway with ice and water.
- Lift the cheesecloth by its edges and twist and squeeze tightly over strainer to press out more buttermilk. When butter starts to squeeze through the cloth, you are done. Transfer the cheesecloth-wrapped butter to your ice bath and let it rest there till it’s firm to the touch, about 2 minutes. Pour the buttermilk into an airtight container to save it. Do not wash the bowl.
- Remove butter from the cheesecloth and transfer it to the now-empty bowl. Stir and press with a wooden spoon for 1 to 2 minutes to force out additional buttermilk. Drain this buttermilk from the bowl, add to the buttermilk container, and refrigerate until ready to use. If you want salted butter, knead ¼ teaspoon salt into butter with the wooden spoon. Transfer butter to separate airtight container and refrigerate until ready to use. (Butter can be refrigerated for up to 2 months.)
Cultured Butter–Making Tips
- Cream fermented for 24 hours will make a sweetish butter with just a hint of tang. As the aging process continues—especially at warmer room temperatures—the cream gets more and more pungent. After a week it may smell almost too strong for some tastes, but most of what you smell resides in the liquid portion that gets separated out, leaving the butter surprisingly mellow.
- You can use your new homemade buttermilk to culture your next batch of cultured butter. Keep the culture going!
- Homemade cultured butter also makes incredible browned butter. Try it on your next pasta dish.