Have you ever wondered why pasteurized milk is common these days? Milk is a staple food item that is consumed by millions of people around the world. It is a rich source of nutrients that are essential for the growth and development of the human body. However, the nutrients are the same reason why milk can also be a potential source of harmful bacteria called pathogens. This is why the process of pasteurization is so important for public health and safety.
Pasteurization is a process that involves heating milk to a specific temperature for a certain amount of time to kill any harmful bacteria that may be present. This significantly reduces the risk of bacterial infections and diseases. During Pasteur’s time, contaminated milk was a significant contributor to disease outbreaks, especially in urban areas. The introduction of pasteurization provided a reliable means to eliminate harmful microorganisms in milk. This curtails the spread of diseases like typhoid fever, tuberculosis, and brucellosis.
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The introduction of pasteurization helped safeguard public health by ensuring the safety of a widely consumed food item. Today, pasteurization is a standard practice in the food industry for various products, including milk, fruit juices, and canned goods. It has become an integral part of food safety regulations in many countries with strict guidelines governing the pasteurization process to ensure its effectiveness.
In this article, we will explore the process of producing pasteurized milk, and why it is essential to consume milk that has been properly pasteurized.
THE PROCESS OF PASTEURIZATION
The primary step in pasteurization of milk involves subjecting the liquid to a specific temperature and holding it at that temperature for a defined period. The exact temperature and time combination depend on the type of product and regulatory requirements. For example, in high-temperature short-time (HTST) pasteurization, the liquid is heated to around 72°C to 75°C (162°F to 167°F) for approximately 15 to 30 seconds. In contrast, low-temperature long-time (LTLT) pasteurization involves heating the liquid to around 63°C (145°F) and holding it for at least 20 to 30 minutes.
After the liquid has been heated, it is rapidly cooled to a temperature below which microorganisms can thrive. Cooling may be achieved through various methods, such as passing the liquid through a heat exchanger, where it is rapidly cooled with cold water, or through indirect cooling using refrigeration equipment. The quick cooling helps to halt the growth of any remaining microorganisms and preserves the product’s quality.
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Once the pasteurization process is complete, milk is packaged in containers that are sealed to maintain its safety and freshness. Proper packaging is essential to prevent recontamination and ensure the product’s longevity. Pasteurized products are typically stored under refrigeration to further inhibit the growth of any surviving pathogens.
THE BENEFITS OF PASTEURIZED MILK
One of the primary benefits of pasteurization is the significant reduction of harmful bacteria in milk. The process effectively eliminates or reduces pathogens such as Salmonella, Escherichia coli, Campylobacter and Listeria monocytogenes, which can cause serious foodborne illnesses. By destroying these pathogens, the milk becomes safe for consumption, reducing the risk of infections and diseases.
And since pathogens have been destroyed, pasteurized milk is more shelf-stable than raw milk. By heating the milk to a specific temperature, bacteria that can spoil the milk and cause off-flavors or odors are destroyed. This extended shelf life improves the availability of milk, reduces food waste, and provides consumers with a reliable supply of fresh milk for a longer period. When refrigerated, pasteurized milk can last up to three weeks, while raw milk, on the other hand, can only last for up to ten days.
It’s worth noting that pasteurized milk should still be handled and stored properly to maintain its quality and safety. Refrigeration is necessary to inhibit the growth of any remaining bacteria and maintain the freshness of the milk.
Perhaps the biggest misconception about pasteurization is that it reduces the nutritional value of milk. Well, pasteurization is a mild heat treatment. It aims to strike a balance between ensuring food safety while preserving the quality and nutritional value of the product. Pasteurization is designed to selectively target and eliminate or reduce specific pathogens while preserving the desirable characteristics of the product. As earlier mentioned, pasteurization temperature is around 162°F to 167°F (72°C to 75°C). This temperature range is below the boiling point of water, allowing for better retention of beneficial nutrients.
On the contrary, pasteurized milk is often fortified with vitamin D, which raw milk is naturally low in. Vitamin D is essential for better calcium absorption in the body.
