French butter keeper instructions
Learn how to use your ceramic butter keeper to keep your butter creamy and fresh outside of the fridge.
What is a french butter keeper?
A french butter keeper is a lidded vessel used to keep your butter fresh and at a perfect spreadable consistency outside of the refrigerator. It is a two part design that originated in the 19th century: a base that holds water, and a lid with a cavity for holding butter.
The science:
Water in the base of the butter keeper helps to create an air-tight seal around the butter preventing the fats (mostly a mixture of triglycerides) from oxidizing and creating off or rancid flavors.
As the butter gets used down, it will have some of its surface touching air in a bubble. The air in this bubble is trapped and not getting new oxygen from the rest of the atmosphere therefore significantly slowing the oxidation process down.
If you're going through a stick every day or two, this isn't critical, but if your butter stays out for a week or longer, you'll notice the difference.
Step 1: Fill the lid with butter
Start by bringing one to two sticks of butter to room temperature. Once it has reached room temperature, take a knife (or your fingers if you don’t mind a little grease) and pack it in tight to the lid cavity. The butter should be flush with the lip of the cup like pictured.
STEP TWO: put water in the base
The second and final step is to fill the base with about an inch or two of water. You want enough water to where it is coming in contact with the butter in the lid cavity once you put it back on the base. You will want to refill your water about once a week. I also like to add in a pinch of salt to prevent mold from forming when my kids inevitably drop their crumbs and jelly into the water.
And that’s it!
Notes: During sweltering Vermont summer days (85+ degrees F) and the absence of air conditioning or a cool basement, it is sometimes necessary to ride out the heatwave with your butterkeeper in the refrigerator.