A French butter dish is a container used to maintain the freshness and spreadable consistency of butter without refrigeration. This late 19th-century French-designed pottery crock has two parts: a base that holds water, and a cup to hold the packed butter which also serves as a lid. The cup containing butter is placed into the base, where water creates an airtight seal that keeps the air (and thus oxygen) away from the butter so that refrigeration is not needed, and the butter can be used in its soft form. This method will keep butter for around a month provided it is kept at temperatures below 80 °F (27 °C) and the water is changed regularly.[citation needed]
Other names for this item are "French butter keeper", "French butter crock", "butter crock", "beurrier à l'eau", "beurrier Breton", "beurrier Normand", "cloche de beurre", "pot à beurre Breton", and "französische Butterdose" (German). Two manufactured versions are the Norpro butter keeper and the Butter Bell, a registered trademark of L. Tremain, Inc.[1][2]
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