Cultured butter: an experiment

Butter is central to so much cooking, from the classical to super modern, whether gluttonous or health foods. It adds richness and flavour, emulsifies sauces and is even responsible for the flaky layers in puff pastry. We’re reasonably accustomed to seeing salted and unsalted varieties and can find a vast array from the raw, unpasteurised and posh to the dubiously bright yellow with ease. However, I’d never seen cultured butter on a shelf, or even heard of it until pretty recently. Knowing it had something to do with fermentation (and you’ve heard me bang on about the rituals of making sourdough and kimchi) and reading about Apollonia Poilâne’s recipe for cultured butter on The Chalkboard, I thought I’d give it a go. If normal bread and butter are a near perfect combination, what of cultured butter and sourdough?

When making your own butter (regardless of whether it’s cultured or not) you also get the wonderful by-product of buttermilk, which means I’ll have to make buttermilk chicken or pancakes or something. What a shame.

What is cultured butter?

Cultured butter is made from fermented cream that has had bacteria introduced in its final stage of production. The bacteria, when making it at home at least, comes from yogurt or buttermilk and is then left to ferment for up to 48 hours. This gives the butter a nutty, slightly sour flavour and is believed to aid in digestion.

Cultured butter can be found in delis and health food shops, but it will be reasonably expensive, so making it yourself is a lot cheaper and also a pretty fun weekend project.

How does fermentation work?

Fermentation in cultured butter works when the bacteria from yogurt or buttermilk set to work eating the sugars (lactose) in the as yet unchurned cream. By leaving the cream and yogurt/buttermilk combo at room temperature for 24-48hrs the conditions for the bacteria are prime. This produces lactic acid, which changes the cream’s flavour, giving it that sour edge.

This process is the same in making yogurt and cheeses.

More from Mildred’s Kitchen

Benefits of fermentation

Fermentation has come to be seen as central to gut-friendly health foods. Your gut contains loads of different types of bacteria, which together make up your gut microbiome or intestinal flora, some of which are more beneficial than others. Fermented foods contain probiotic bacteria, so by eating them you are boosting the good guys. This improves the overall health of your gut microbiome, which in turn helps you to maintain a strong immune system.

5 ways to use cultured butter:

  • Use in soups and sauces – cultured butter beurre blanc anyone?
  • Melt a knob of cultured butter over veg – peas, new potatoes or carrots would be particularly good.
  • Swap out normal butter for cultured in mashed potato (or mashed sweet potato).
  • Simply pile high on freshly baked bread – make it sourdough for a super gut-friendly version.
  • Use in pastries and baked goods – particularly savoury ones – it would be great with cheese.

How to make cultured butter


2 cups heavy cream, preferably not ultra-pasteurized
2 tbsp plain yogurt (any style; be sure the label specifies “live active cultures”)
ice water
¼ tsp fine sea salt (optional)


  1. 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.
  2. 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.
  3. 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.
  4. 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.
  5. 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.

Cultured Butter is excerpted from Poilâne: The Secrets of the World-Famous Bread Bakery © 2019 by Apollonia Poilâne.