Cream is the thick white-pale yellow liquid which naturally rises to the top when milk is left to stand. With a fat content ranging between 20- 50 %, it is a luxury dairy product that is often used as an accompaniment to desserts or as an ingredient in sweet or savoury dishes. Commercially, cream is produced by centrifugation of milk, which is a simple separation method that allows the less dense cream component of milk to rise to the top for removal.
Cream with a fat content of 35% or higher can be frozen. Low-fat creams (e.g. single cream) are not as suitable for freezing because they tend to separate and go watery upon thawing.
The difference between single, double, whipping and cooking cream is essentially the milk fat content. The desired milk fat content can be achieved through a separation process called centrifugation. Single cream must contain a minimum milk fat content of 18%. Double cream must contain a minimum milk fat content of 48%. Whipping cream must contain a minimum milk fat content of 38%. Finally cooking cream must contain a minimum milk fat content of 19%.
Clotted cream contains a minimum of 55-60% milk fat. Due to its higher fat content and lower water content, it has a much thicker consistency than regular cream. Production of clotted cream involves heating whole milk , and then allowing it to cool slowly in shallow trays. The cream rises to the top and forms a thick crusted layer of ‘clots’ that can be easily separated from the skimmed milk portion. Clotted cream is slightly yellow in colour.
Both sour cream and crème fraîche are fermented milk products, made from cream. The cream is fermented with bacterial cultures which produce lactic acid, causing the cream to sour and thicken, giving a smooth viscous product. Crème fraîche usually has a higher fat content and is not quite as soured as sour cream and tends to have a richer, less tangy flavour. Thickening agents such as gelatine, guar gum or vegetable enzymes are sometimes added to sour cream, particularly to reduced-fat or ‘light’ varieties but are less often added to crème fraîche. Both are often used in dips or as an ingredient in soups or sauces.