The process of pasteurisation in the food Industry
Pasteurisation is a necessary procedure in the treatment of milk and the majority of dairy products, mainly food items such as yogurt, cheese, and butter, clearly derived from milk. The structures used in their production depend on the use of highly specialised equipment which permits the elimination of harmful organisms from the dairy products.
During the pasteurisation procedure, a dairy product undergoes a treatment at a high temperature: in this way it is possible to eliminate certain bacteria and other organisms, but without altering the characteristics (both in terms of shape and taste) of the dairy products. Each product in the dairy category requires heating to a different temperature, when pasteurised.
There are two main reasons for the pasteurisation of dairy products: to eliminate the bacteria, thus making these foods edible for humans, and to improve their quality.
Dairy products must be subjected to this treatment before they are bottled or packaged for delivery and sale. In America, for example, the U.S. Food and Drug Administration has in fact declared it a necessary procedure for the vast majority of frozen and chilled products.
The pasteurisation of a food reduces the risks linked to pathogenic bacteria, and at the same time significantly limits the presence of micro-organisms responsible for the deterioration of the foods, which would make them expire before the actual expiry date!
Bacteria can still continue to grow after the product has been pasteurised, but mould and other toxic bacteria will form only after the expiry date.
Some foods are pasteurised and then packaged immediately in order to reduce their exposure to oxygen, to protect them from potentially harmful micro-organisms.
In any case most pasteurisation procedures involve heating the product and then immediately cooling it by bringing it to a pre-determined temperature.
Translated by Joanne Beckwith
