a minimum of 80% butterfat; in practice, most American butters contain only slightly more than that, averaging around 81% butterfat. European butters generally have a higher ratio, which may extend up to 85%.

cid. The fermentation process produces additional aroma compounds, including diacetyl, which makes for a fuller-flavored and more "buttery" tasting product.[10] Today, cultured butter is usually made from pasteurized cream whose fermentation is produced by the introduction of Lactococcus and Leuconostoc bacteria.


Chart of milk products and production relationships, including butter.
Another method for producing cultured butter, devmed the cream themselves, and made butter with it. It is rare in Europe as well.[12]
Several "spreadable" butters have been developed; these remain softer at colder temperatures and are therefore easier to use directly out of refrigeration. Some modify the makeup of the butter's fat through chemical manipulation of the finished product, some through manipulation of the cattle's feed, and some by incorporating vegetable oils into the butter. "Whipped" butter, another product designed to be more spreadable, is aerated via the incorporation of nitrogen gas—normal air is not used, because doing so would encourage oxidation and rancidity.
All categories of butter are sold in both salted and unsalted forms. Either granular salt or a strong brine are added to salted butter during processing. In addition to enhanced flavor, the addition of salt acts as a preservative.
The amount of butterfat in the finished product is a vital aspect of production. In the United States, products sold as "butter" are required to contain a minimum of 80% butterfat; in practice, most American butters contain only slightly more than that, averaging around 81% butterfat. European butters generally have a higher ratio, which may extend up to 85%.


Clarified butter
Clarified butter is butter with almost all of its water and milk solids removed, leaving almost-pure butterfat. Clarified butter is made by heating butter to its melting point and then allowing it to cool; after settling, the remaining components separate by density. At the top, whey proteins form a skin which is removed, and the resulting butterfat is then poured off from the mixture of water and casein proteins that settle to the bottom.[13]
Ghee is clarified butter which is brought to higher temperatures of around 120 °C (250 °F) once the water had evaporated, allowing the milk solids to brown. This process flavors the ghee, and also produces antioxidants which help protect it longer from rancidity. Because of this, ghee can keep for six to eight months under normal conditions.[13]
Cream may be skimmed from whey instead of milk, as a byproduct of cheese-making. Whey butter may be made from whey cream. Whey cream and butter have a lower fat content and taste more salty, tangy and "cheesy".[14] They are also cheaper than "sweet" cream and butter.
European butters[edit]
There are several butters produced in Europe with Protected geographical indications; these include:
Beurre d'Ardenne, from Belgium
Beurre d'Isigny, from France
Beurre Charentes-Poitou (Which also includes: Beurre des Charentes and Beurre des Deux-Sèvres under the same classification), from France
Beurre Rose, from Luxembourg
Mantequilla de Soria, from Spain