VACREATION/DEODORIZATION OF CREAM.

Cream has the ability to absorb off-flavours from the environment following poor storage, from feeds given to the animal eg Onion off-flavour and also from biochemical processes due to enzymatic and microbial activity. If these flavours are present in the cream, they will be carried over to the product imparting the unacceptable flavours to the product.

Vacreation or deodorization is the process of cream treatment to remove such flavours. It involves a vacuum treatment where the cream is pumped into a vacuum chamber (deodorizer) at about 78 0C and then pumped to a vacuum chamber where the pressure corresponds to a boiling temperature of 62°C. The reduced pressure causes volatile flavouring and aromatic matter to escape in the form of gas when the cream is flash-cooled.

The released volatiles are sucked out by using a vacuum pump. After this treatment, the cream is returned to the heat exchanger for pasteurisation and cooling, and then continues to the ripening tank.

Vacreation can also be done through a vacreation system which consists of three stages;

i)?????? Heating the cream instantaneously suing steam by direct heat injection under pressure to a desired temperature(? 92-950C) at 500-600mmHg for 4 seconds( first chamber)

ii)???? The product is then passed to a second chamber maintained at a lower pressure where boiling occurs for the removal of gases and volatile substances and excess steam in the water condenser (75-800C) at 340mmHg.

iii)?? The product is then passed through a third chamber maintained at nearly vacuum where boiling occur for additional removal of water and gases. The chamber also acts as a cooling chamber (450C) at 90mmHg.