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Crème fraîche is a traditional French cultured dairy product consisting of heavy cream that has been inoculated with lactic acid bacteria and allowed to ferment and thicken. The fermentation process, which typically takes 8-24 hours, creates a tangy, slightly sour flavor profile and increases the natural acidity of the cream from approximately 0.5% to 1-2%. The result is a luxuriously thick, spoonable product with a distinctly higher fat content (40-45%) compared to sour cream (18-20%), lending it a richer, more velvety texture and milder sour notes.\n\nWhile crème fraîche originated in France, it is now produced internationally with regional variations in fermentation duration and bacterial cultures. True French crème fraîche undergoes minimal processing and contains no additives or stabilizers, maintaining a delicate balance between tangy fermentation and creamy richness. The ingredient remains stable when heated, unlike sour cream, making it particularly versatile in both hot and cold applications.

Crème fraîche serves as a finishing element and cooking ingredient across French and international cuisines. In French cookery, it is essential for enriching sauces, particularly in classic preparations such as coq au vin and stroganoff, where its stability at high temperatures prevents curdling. It is commonly dolloped onto soups (especially beet and potato varieties), desserts, and fresh berries, and whipped into a mousse-like topping for pastries and cakes. In Nordic and Eastern European cooking, it functions similarly to sour cream but with greater richness. The ingredient also appears in salad dressings, dips, and as a garnish for smoked fish and caviar.\n\nBecause crème fraîche does not curdle when boiled, it can be incorporated directly into reductions and pan sauces without tempering. It pairs particularly well with acidic ingredients, herbs (especially dill and tarragon), and fresh berries.