The major difference in drinking raw unprocessed and pasteurized milk is in its bacterial count. In the subtropical and developing countries where milking is still a small scale hand-operated task, in the marginal area of farms, the initial bacterial count of raw milk reaches up to 2-3 lacks bacteria/ml. Even though we are boiling milk in the kitchen, the cooling happens at a natural slow speed. In this time the spores (eggs or dormant bacterial cells) again germinate between 55-65°C temperature range. In industrial pasteurization, however, the milk is RAPIDLY COOLED to below 5°C before spores are germinated. this brings down the bacterial population to below 20,000/ml in pasteurized milk and practically ZERO in UHT sterilized milk.
FSSAI has made regulatory standards for all food products that allow maximum of 20k bacterial cells in milk samples. If any 2 or more samples out of 5 are found above 20k, or even 1 out of 5 is above 50k, the entire batch is compulsorily reprocessed before it reaches the shelf. COURSE, WE CANNOT ACHIEVE THIS EFFECT IN OUR KITCHEN making it safest to drink only pasteurized/ heat-treated milk.
B.Tech (Dairy Technology) Student
This article by Ashish Sahuji is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Based on a work at www.profdumbledairy.com.