As the H5N1 avian flu virus continues to spread among poultry and dairy cattle, concerns over the safety of the U.S. milk supply have surged. However, the U.S. Food and Drug Administration (FDA) assures consumers that pasteurized milk remains safe for consumption.

In late November 2024, California regulators were compelled to recall batches of raw, unpasteurized milk from a Fresno dairy farm after they detected the avian flu virus. Following this alarming discovery, the dairy facility launched a complete recall of its raw milk and cream products, and state officials imposed a quarantine, halting any further distribution of its raw dairy goods following November 27. While no human cases of bird flu linked to these products were reported post-recall, consumers were strongly advised against consuming raw milk from the affected batches.

Interestingly, despite the potential danger posed by avian flu and other pathogens found in raw milk, sales of these unpasteurized products are on the rise in the U.S. Notably, public figures such as Robert F. Kennedy Jr. have made claims about the health benefits of raw milk, directly contradicting advisories from FDA officials and food scientists.

As an extension food scientist in a state where raw milk sales are legal, I provide guidance to dairy processors to ensure the creation of safe, high-quality products. It is vital for consumers to understand the perils associated with unpasteurized milk, especially in the extra context of current health advisories.

Understanding the Risks: What Makes Milk Unsafe?

Dairy products inherently carry risks that may lead to illnesses or even fatalities. The environments where dairy animals graze and live offer numerous points of pathogen contamination. These include listeria monocytogenes, which originates from environmental sources, and can lead to serious health complications, particularly in pregnant women. Other dangerous pathogens associated with dairy include E. coli, Campylobacter, and Salmonella, each posing significant health threats.

The Evolution of Pasteurization

In the 1860s, French microbiologist Louis Pasteur pioneered the concept of pasteurization to eliminate spoilage microorganisms from beverages. This technique, widely adopted in the U.S. before World War II, significantly curbed foodborne illnesses that were previously attributed to unpasteurized milk, which caused a staggering 25% of all U.S. foodborne illness outbreaks at that time. The federal government eventually mandated the pasteurization of all milk sold across state lines in 1973, cementing this process as essential to public health.

Pasteurization involves heating milk to specific temperatures for designated periods to eradicate even the most heat-resistant pathogens. Rigorous scientific research has been conducted to optimize these parameters to ensure safety.

Types of Pasteurization: Ensuring Safe Dairy Products

Dairy processors utilize several methods for pasteurization. All of them, when done correctly, render milk safe from pathogens: 1. Vat Pasteurization: Ideal for smaller-scale producers, heating milk to a minimum of 145°F (63°C) for 30 minutes. 2. High-Temperature Short-Time (HTST) Pasteurization: Commonly used commercially, involves heating milk to 161°F (71°C) for at least 15 seconds. 3. Ultra-Pasteurization: Involves heating milk above 285°F (140°C) for a few seconds, yielding an extended shelf life.

Ultra-high-temperature packaged products can remain shelf-stable for up to a year, making them an excellent option for convenience without compromising safety.

Emerging Threats: The Avian Flu in Milk

The recent identification of avian flu virus traces in milk signals a new challenge for the dairy sector. Emerging research suggests that although the virus can reach cow's milk, pasteurization effectively inactivates it. However, because scientific understanding of transmission remains limited, the FDA continues to warn against the consumption of raw milk. Moreover, producers are urged not to process milk from sick cows.

With H5N1 continuing to emerge in new species, as seen with recent human cases involving a child in California and a teenager in Canada, it remains crucial for consumers to heed warnings about raw milk. Young individuals may be particularly vulnerable to infections arising from undercooked or unprocessed dairy items.

In light of ongoing research and health advisories, the message is clear: the risks of consuming raw milk are simply not worth taking. It’s a matter of ensuring that the milk on your table is not just tasty, but safe too!