Frozen Cream

As the name suggests the cream in frozen state is called frozen cream. Freezing of cream inhibits bacterial growth. It is prepared to improve keeping quality of cream so that it can be transported without spoilage over a long distance in a refrigerated van. Freezing also helps to store surplus cream for use during shortage.Ice-cream manufacturers use most of the frozen cream. It is also used in recombined milk and cream soups. Addition of 10-15% sucrose by weight to cream before freezing is helpful in preventing oiling-off after thawing of frozen cream. During freezing ice crystals are also formed. These crystals rupture the membrane enclosing the fat globules. Frozen cream, therefore, tends to oil-off on thawing especially at higher temperature. Oiling-off in cream also impairs whipping property of the product. Preparation of frozen cream also starts with collection of good quality of milk, its filtration and separation. Resulting cream is then standardized to contain 40-50% fat and then pasteurized. Pasteurization is done by heating cream at 74°C for 30 minutes in a batch type of pasteurizer or plate heat exchanger. The heated cream is cooled after the holding period to 4°C. The pasteurized and cooled cream is then filled in paper/plastic containers or cans and sealed. These containers are then transferred to a freezing chamber maintained at a very low temperature (-20°C). The cream freezes after a sometime in the containers. The frozen cream is stored below -12°C. Preparation of frozen cream involves the following steps as shown in Fig.

Flow diagram for preparation of frozen cream

Freezing of cream could also be achieved by employing any of the following methods:

i)Blast freezing chamber- Bulk containers, containing cream, are allowed to pass through a chamber where they meet a current of chilled air effecting freezing.

ii) Plate freezers

iii) Rotating drum freezers

iv) Cryogenic freezing tunnels