The co-operative farmer members take milk in clean and covered
vessels to the village dairy co-operative society managed by
the producer members.
in its natural state, contains numerous microorganisms which
double in every 15 to 20 minutes and add greatly to its deterioration.
To avoid this and to ensure good quality raw milk, chilling
of milk at the village level through bulk milk coolers (BMCs) has been initiated.
The practice of chilling milk at the village level is being
increasingly adopted by the co-operative societies. At the dairy
society, a milk sample is taken and tested for the Fat and SNF
%age and any impurity. Testing of milk is done using gerber
method of testing milk fat and lactometer for SNF. In many village
coops now milk is tested using electronic milkotester and SNF
analysers. Farmer members are paid on the quality of the milk
they pour (fat and SNF %age in milk) rather than the quantity
of milk poured alone.
the milk is procured by the village dairy co-operatives and sent
in clean milk cans / milk trucks to the district union dairy
where it is subjected to some organoleptic tests, sampled, weighed
and tested before processing.
The milk received from the village society is processed and packed by the district union before it reaches the consumer. The different stages of processing are:
On arrival at the dairy/chilling centre, milk is immediately cooled to 4 - 6 °C and stored in storage tanks / silos.
The chilled milk from the silos goes to the clarifier after preheating. The clarifier spins the warm milk at a high speed, removing dust and dirt particles invisible to the naked eye.
The milk is then pasteurized. Named after Louis Pasteur, a French
Scientist who invented the process for use in wine, pasteurization
was first applied to milk by Dr. Soxhlet of Germany. This involves
heating the milk to 72 °C and holding at this temperature for
15 seconds. Other equivalent time-temperature combinations may
also beused. After heating and holding, the milk is rapidly
cooled to a temperature of 7 °C or below. Pasteurization of milk
results in heat destruction of all the pathogenic (disease causing)
bacteria and about 90% reduction in the number of spoilage bacteria.
The surviving bacteria do not get opportunity to proliferate
due to the rapid cooling of milk after heating. Pasteurization
inactivates even the TB bacteria. Therefore, it is always healthy
to drink pasteurized milk.
The milk then proceeds to a homogenizer. This is where the large size fat globules present in milk are broken down into tiny particles of less than 2 micron size. The reduced size fat globules cannot rise to the top in the milk to form a cream layer. The milk fat gets evenly distributed, thus also making the milk appear whiter and thicker. Homogenization is done for consumers who do not like cream layer (malai) on top of the milk. However, for those who like malai in milk, it is not homogenized.
Milk from different breeds of cows and buffaloes may vary in its composition. Hence, to make milk of uniform composition for supply to market it is standardized by raising or lowering, of the fat and/or solids-not-fat percentages of milk to a desired value, so as to conform to the legal or other requirements prescribed.
Traditionally the co-ops used to pack milk in glass bottles. However, now all co-op milk is packed in plastic pouches/tetrapacks / bulk vending etc.
Benefits of packaged milk Packaging of milk has undergone remarkable innovations in the past few decades. Milk stored in bottles now belongs to a bygone era. Tamper proof, hygienic and labeled pouches / packs have replaced the traditional bottle. These innovative methods of packaging milk have rendered it free from adulteration and tampering. They have also made it possible to provide consumers with different variants of milk labeled and color coded to their requirements. Aseptic packaging has given milk a shelf life of 120 days without refrigeration - something unthinkable a few decades back! After packaging and final quality clearance, the milk is ready for transportation to retail shop / vending machines, in insulated trucks.