Homogenized Milk

Milk and dairy products are among those food items that have been used by humans for a very long time. It is claimed to be a nutritious food source and is consumed by people in almost all parts of the world. While raw milk was used by ancient people, today, we have a wide range of milk types like pasteurized, homogenized, organic and low-fat.

Pasteurization of Milk

According to archaeological evidences, humans have been using milk as early as 6500 B.C. It is believed that humans evolved the capability of digesting raw milk, after thousands of years from this period. With time, people started processing milk in many different ways. The French chemist and biologist Louis Pasteur developed the method of pasteurization, in 1863. This method was a milestone in food processing industry, which use it for killing harmful microorganisms like bacteria, in milk and other beverages and food products. This was followed by various inventions, automatic milking equipment, milk jars and milk cartons. Pasteurization involves heating of milk for a short time and then cooling it, till distribution. Even pasteurized milk is perishable and so, newer methods were introduced in milk processing, so as to increase its shelf life. Such methods include ultrapasteurization or ultra-high temperature treatment, microfiltration, creaming and homogenization.

What is Homogenized Milk

It is a common fact that milk is an emulsion of oil and water. The fat molecules in milk have the tendency to segregate and form a top layer. This may not be seen in fresh milk, but, with time, milk develops this fat layer, as fat molecules are less denser than water. Even pasteurized milk is not free from developing this layer. Homogenization is a processing method that prevents the formation of this fat layer. In this process, milk is subjected to very high pressures, as it is pumped through narrow tubes. This breaks down the fat molecules which get much smaller in size. These molecules are dispersed evenly, so that they do not segregate and form the cream layer on top. Even the fat content in milk is reduced with this process.

It is said that around 2% of the milk fat content is reduced with homogenization, which is preceded with pasteurization. But, you may also get homogenized milk with different fat levels like 2%, 4%, etc. This is very important, as the broken down fat molecules may turn rancid, as they are exposed to certain enzymes in milk. Pasteurization deactivates these enzymes. Such milk is found to be a little bit bland in taste and is more whiter in color. This milk is less prone to get rancid and develop off flavors. It is said that ultra homogenization improves milk shelf life than regular homogenization, under low pressure. While homogenization improves the creamy texture and color of milk, there are various contradictory opinions about the health aspects of this milk.

Homogenized Milk Dangers

While this milk is said to be easily digestible, there are various claims regarding its ill effects on health. It is contended that there are some proteins in this milk that can lead to heart diseases, as they are not digested, but, carried through the bloodstream. This enzyme called XO settles in the arteries, thereby increasing the risk of heart attacks. According to a study conducted by the Harvard University, homogenized milk may increase the risk of bone fractures. This type of milk has also been linked to various other medial conditions like anemia, ovarian cancer, prostate cancer, rheumatoid arthritis and leukemia. It is also said that, if there is any nutrition left after processing the milk through pasteurization and homogenization, the body may not be able to absorb those milk nutrients.

This was only a brief overview about homogenized milk, the process of homogenization and its so-called dangers. Even though, there are various claims regarding the benefits as well as the dangers of this type of milk, there is no conclusive evidence to prove the same.