Cultured butter is basically like regular butter but with one very important extra step. After pasteurization, butter makers will carefully add live bacterial cultures back into their recipe to facilitate fermentation. Fermentation gives the butter a distinctly delicious flavor, but — most importantly — makes it easier to digest. If you don’t happen to be living in a farmhouse in the countryside somewhere in Europe, you can make cultured butter with a few simple steps as mapped out in the modern classic cookbook from Poilâne bakery and the Poilâne family, aptly named, Poilâne…
In France and other parts of Europe, butter is cultured by adding live bacteria to the cream before churning. The cream sits at room temperature long enough to ferment (culture). The result is butter with a slight tang and nuttiness. You can buy cultured butter, but it’s easy—not to mention fun—to make it at home. (Bonus: After you “churn” the cream, there will be some residual liquid—i.e., buttermilk.)
Because there are so few ingredients, buy the best you can. For the cream, look for one with a high percentage of fat and try to avoid ultra-pasteurized, which tends to have less flavor. For the yogurt, be sure it has active cultures and, for best flavor and texture, avoid those with added stabilizers; the ingredient list should contain only milk and yogurt cultures.
Homemade Cultured Butter
Makes about 8 ounces butter + 1 cup buttermilk
2 cups heavy cream, preferably not ultra-pasteurized
2 Tbsp plain yogurt (any style; be sure the label specifies “live active cultures”)
¼ tsp fine sea salt (optional)
In a medium bowl, whisk together the heavy cream and yogurt until combined. Cover with cheesecloth or perforated plastic wrap. Let stand at room temperature until the mixture has thickened slightly and gives off a slightly sour and tangy aroma, at least 18 hours, and up to 24 hours. Then refrigerate for 1 hour, or until chilled.
Transfer the cream mixture to a food processor and process until the curds begin to separate from the buttermilk, 3 to 4 minutes; the mixture will look like liquidy cottage cheese.
Line a fine-mesh sieve with cheesecloth and set it over a bowl. Strain the curd mixture through the cheesecloth. Gather the edges of the cheesecloth up around the solids and squeeze to force out as much of the liquid as possible. Remove the solids from the cheesecloth and place in a medium bowl. Refrigerate the liquid, which is buttermilk, for another use.
Pour ½ cup ice water over the solids and, using a rubber spatula, “wash” the butter by folding it over itself and pressing down to extract any remaining buttermilk. Drain off the milky liquid and discard it. Repeat the process, adding more ice water, until the liquid remains clear, which may take 4 or 5 rinses. The butter will start to harden, and it may become easier to work with your hands.
Lightly pat the butter dry with paper towels. If using salt, knead it in. Pack the butter into a bowl or jar and cover tightly, or roll it into a log and wrap in wax or parchment paper. The butter will keep in the refrigerator for about 3 weeks or in the freezer for several months.
Homemade Cultured Butter is excerpted from Poilâne: The Secrets of the World-Famous Bread Bakery © 2019 by Apollonia Poilâne. Photography © 2019 by Philippe Vaurès Santamaria. Reproduced by permission of Houghton Mifflin Harcourt. All rights reserved.