[2][3] Crème fraîche is produced by adding a starter culture to heavy cream and allowing it to stand at an appropriate temperature until it thickens.

[5][6] In some places in Europe, the fat content of crème fraîche is regulated, and it may not contain ingredients other than cream and starter culture.

[1] In North America and the UK, products labeled "low-fat crème fraîche" with approximately 15% butterfat and with added stabilizers such as xanthan gum or starch from maize or corn, are commercialized.

The structure of crème fraîche consists of an acid gel composed of milk protein-covered fat globules that tend to agglomerate.

These triglycerides will tend to crystallize inside the fat globule adding to the gel's stiffness.

and the crème fraîche from a defined area around the town of Isigny-sur-Mer in the Calvados department of Normandy is highly regarded.

[11] It also is produced in many other parts of France, with large quantities coming from the major dairy regions of Brittany, Poitou-Charentes, Lorraine, and Champagne-Ardenne.

It often is used to finish hot savory sauces, and with its fat content greater than 30%, curdling is not a problem.