Recent reports say that the H5N1 bird flu virus has been present in cow's milk Questions raised about whether the U.S. milk supply is drinkable. According to the Federal Food and Drug Administration, the reply is yes. so long as the milk is pasteurized.
Nonetheless, Sales of raw (unpasteurized) milk have increaseddespite warnings from health experts that it could contain raw milk high concentrations of the virustogether with many other pathogens.
As Extension Food Scientist in a state where the sale of raw milk is legalI provide technical support to assist processors produce top quality and secure dairy products. I also wish to help people understand the confusing world of pasteurization methods on their milk labels and why experts strongly advise against consuming raw milk and products constructed from it.
What could make milk unsafe?
Dairy products, like many foods, pose risks that may lead to numerous illnesses and even death. Our milk comes from animals that graze outdoors and live in stables. The milk is picked up from the farm by tanker trucks and delivered to the processing plant. These environments provide quite a few opportunities for contamination by pathogens that cause disease and organisms that cause food spoilage.
For example, Listeria monocytogenes comes from environmental sources akin to soil and water. Mild infections with listeriosis cause flu-like symptoms. Unfortunately, more serious cases are too common and might result in miscarriages in pregnant women in extreme cases even death.
Other pathogens commonly related to dairy animals and raw milk These include E. coliwhich may cause serious gastrointestinal infections and result in kidney damage; Campylobacter, the leading reason behind diarrheal illness within the United States; And Salmonellawhich cause abdominal pain, diarrhea and other symptoms.
Store drinks safely with heat
In the 1860s French microbiologist Louis Pasteur discovered that heating wine and beer killed the organisms that caused spoilage, which was a big problem in France on the time.
This heating process, generally known as pasteurization, was introduced within the United States before World War II, at a time when milk was the norm 25% of all foodborne disease outbreaks within the US. In 1973, the federal government required that every one milk sold across state lines within the United States be pasteurized, and in 1987 this became the case Prohibition of interstate sales of raw milk.
Pasteurization involves heating each particle of a food to a selected temperature over a continuous time period to kill the product's most heat-resistant pathogen. Different organisms react otherwise to heat. Therefore, controlled scientific studies are needed to find out how long a given organism will kill at a given temperature.
Since 1924, the policy has guided pasteurization within the United States Class “A” pasteurized milk regulation.a federal guide that’s updated every two years to reflect the present state of science and was adopted by all 50 states. Pasteurization equipment within the United States must meet strict requirements, including sanitary design, safety controls, and material standards.
Jack Delano, FSA/Library of Congress
Pasteurization methods
Dairy processors can choose from several types of pasteurization. When used accurately, all of those methods produce the identical result: pathogen-free milk. To provide a further margin of safety or to scale back bacteria that may cause milk to spoil, processors may treat milk beyond minimum times or temperatures, extending the product's shelf life.
VAT pasteurizers, also called batch pasteurizers, are sometimes utilized by smaller processors that process limited quantities. The milk is pumped right into a temperature-controlled tank with an agitator, heated to at the very least 63 degrees Celsius and kept there repeatedly for half-hour. It is then cooled and pumped out of the vat.
The mostly used method for industrial milk is High-temperature short-term pasteurization, which will be used to treat large quantities of milk. The milk is pumped at high speed through a series of thin plates to achieve a minimum temperature of 71°C. It then travels through a holding tube for 15 seconds, whereby the temperature is robotically checked and cooled for safety reasons.
The most complex and expensive systems are Ultra-pasteurizers and ultra-high temperature pasteurizers, which pasteurize milk in only a couple of seconds at temperatures above 285 F (140 C). This approach destroys many spoilage-causing organisms and provides the milk a significantly longer shelf life than other methods, although products made this fashion sometimes have more of a “cooked” taste.
Ultra-high temperature products are processed in a sterile environment and packaged in sterile packaging akin to lined boxes and bags. They can last as long as a yr before being opened. Ultra-high temperature packaging makes it secure for youngsters to take milk to highschool for lunch on daily basis.
Bird flu in milk
Detecting avian influenza virus fragments in milk is a brand new challenge for the dairy industry. Scientists don't have an entire picture of the risks to humans, but they’re learning.
Previous research has shown that virus particles enter the milk of infected cows, but that The virus is inactivated by pasteurization. However, the FDA advises consumers to not drink raw milk because there is proscribed details about it whether it will probably transmit bird flu.
The agency also urges manufacturers not to provide or sell raw milk or raw milk products, including cheese, constructed from milk from cows that show symptoms of illness.
There's never a superb time to get a foodborne illness, and that is the start of it Ice season. At a time when bird flu is emerging in recent species and scientists are still determining the way it is transmitted, I agree with the FDA that raw milk poses risks not price taking.
image credit : theconversation.com