Discover how UV technology is transforming dairy processing, offering improved safety and nutrient preservation compared to traditional pasteurization methods.
For over 150 years, heat has been our primary weapon against dangerous pathogens in milk. Since Louis Pasteur's groundbreaking work in the 1860s, thermal pasteurization has saved countless lives by eliminating disease-causing microorganisms. But this safety comes at a cost. The same heat that destroys pathogens also damages valuable bioactive compounds in milk—proteins, enzymes, and immunity-supporting molecules that contribute to human health.
Imagine if we could achieve even greater safety without sacrificing these precious nutrients. This isn't a futuristic fantasy; it's happening right now in dairy facilities using ultraviolet (UV) light technology.
As consumer demand for minimally processed, nutrient-rich foods grows, the dairy industry is undergoing a quiet revolution—one powered by light rather than heat.
Uses heat to destroy pathogens but also damages beneficial nutrients
Uses light to eliminate pathogens while preserving nutritional value
Recent FDA approval of UV milk treatment technology marks a pivotal moment for dairy innovation 1 . This article explores how this novel approach works, examines the science behind it, and reveals why UV treatment might soon become the new gold standard for milk safety and quality.
Ultraviolet light occupies a specific portion of the electromagnetic spectrum between visible light and X-rays, with wavelengths ranging from 100 to 400 nanometers (nm). This range is further divided into UV-A (315-400 nm), UV-B (280-315 nm), and UV-C (200-280 nm) 7 . The germicidal properties of UV light are primarily found in the UV-C range, with maximum effectiveness at approximately 254 nm—the wavelength at which DNA absorbs most strongly 2 .
UV-C light at 254nm targets microorganisms
DNA and RNA absorb UV photons
Abnormal bonds form between adjacent genetic bases
Microorganisms cannot replicate and become harmless
The mechanism is both elegant and devastating to microorganisms: when UV-C photons penetrate microbial cells, they're absorbed by the DNA and RNA, causing pyrimidine dimers to form. These are abnormal bonds between adjacent genetic building blocks that essentially "kink" the DNA strand 7 . This damage prevents microorganisms from replicating their genetic material, rendering them harmless and unable to reproduce 2 . It's a physical rather than chemical destruction—like throwing a wrench into精密 machinery.
Traditional thermal pasteurization operates on a different principle—using heat to denature proteins in microorganisms, which unfortunately also damages many beneficial components in milk. Heat-sensitive bioactive compounds like immunoglobulins, lactoferrin, and lactoperoxidase are particularly vulnerable to thermal degradation 1 .
Bioactive Retention
93% retainedEnergy Efficiency
High efficiencyTemperature
3-4°C (cold process)Bioactive Retention
8% retainedEnergy Efficiency
Lower efficiencyTemperature
72-135°C (heat process)UV treatment, by contrast, operates entirely in the cold realm. Milk typically remains at 3-4 degrees Celsius throughout the process, rising only a few degrees 1 . This cold processing environment preserves the delicate structure of bioactive compounds that heat would destroy. As Bob Comstock, CEO of Tamarack Biotics, explains: "All of our testing looks at the bioactive content of these proteins in dairy ingredients, and we have 2–30 times higher concentrations of these" compared to heat-pasteurized products 1 .
While UV treatment works well for clear liquids like water, milk presents a unique challenge: opacity. Milk's turbidity, caused by proteins and fat globules, means UV light penetrates less than 0.1mm—essentially making it a surface treatment 6 . Early attempts to use UV for milk treatment failed because microorganisms hidden in the shadow of milk components could escape exposure.
The key innovation was creating turbulent flow in thin milk layers to ensure all microorganisms receive sufficient UV exposure, overcoming milk's natural opacity.
Tamarack Biotics overcame this limitation with an ingenious engineering solution. Their system uses very thin layers of milk and highly turbulent flows through specially designed quartz tubes 1 . This turbulence constantly renews the milk's surface exposed to the UV lamps, ensuring all microorganisms eventually receive lethal exposure.
For every 100,000 pathogens initially present, only one remains after UV treatment 1 . This meets or exceeds safety standards for traditional pasteurization.
Against mycobacterium avium paratuberculosis (MAP), UV achieves superior reduction compared to thermal methods 1 .
| Factor | UV Pasteurization | Traditional Thermal Pasteurization |
|---|---|---|
| Energy Use | Considerably less energy | Requires significant energy for heating and cooling |
| Bioactive Retention | Retains >93% of immune-active proteins | Retains only ~8% of immune-active proteins |
| Equipment Fouling | Minimal fouling; simple rinse cleaning | Regular fouling requires chemical cleaning |
| Pathogen Reduction | Higher log reduction for some heat-resistant pathogens | May not eliminate all heat-resistant pathogens |
A 2024 study published in the Korean Journal for Food Science of Animal Resources provides compelling evidence for UV's effectiveness in real-world conditions . Researchers designed a systematic investigation to evaluate how UV-C irradiation enhances raw bovine milk quality by targeting spoilage microorganisms.
The findings demonstrated UV-C's potent antimicrobial effects across all milk samples, with the most significant reductions observed in medium and high initial load samples. The treatment proved particularly effective against coliforms, showing higher reduction efficiency compared to other bacterial groups .
| Initial Bacterial Load | Reduction in Standard Plate Count | Reduction in Coliform Count |
|---|---|---|
| Low (<3 Log₁₀ CFU/mL) | Significant reduction observed | Highest reduction efficiency |
| Medium (3-4 Log₁₀ CFU/mL) | Most notable reduction | Higher reduction compared to other bacteria |
| High (>4 Log₁₀ CFU/mL) | Most notable reduction | Higher reduction compared to other bacteria |
UV-C treated milk showed significantly less lipid peroxidation than either pasteurized or untreated milk, even after 72 hours. This suggests UV treatment not only reduces microbial load but may actually help preserve milk quality during storage by limiting oxidative spoilage .
Modern UV processing systems for dairy applications incorporate several crucial components, each serving a specific function to ensure both efficacy and efficiency.
| Component | Function | Specific Examples in Dairy Processing |
|---|---|---|
| UV-C Light Source | Generates germicidal radiation at ~254 nm | Low-pressure mercury lamps; increasingly UV-LED options |
| Quartz Glass Sleeve | Protects lamps while allowing UV transmission | Creates barrier between lamp and milk product |
| Turbulent Flow Chamber | Creates mixing to expose all milk to UV | Thin-film reactors; spiral tube designs 6 |
| Cooling System | Maintains low temperature during processing | Air cooling systems; protective quartz insulation |
| Control Systems | Monitor and adjust UV dose, flow rate | Sensors for intensity, temperature, and flow parameters |
Recent patents describe spiral-wound photobioreactors that leverage centrifugal forces to enhance mixing, and integrated systems that combine UV with other non-thermal methods like ultrasonic pre-treatment 6 . These engineering advances address the fundamental challenge of treating opaque liquids while maintaining the nutritional integrity of the final product.
The implications of UV dairy processing extend far beyond current applications. While Tamarack's FDA approval currently applies to powdered dairy ingredients (whey protein concentrate, milk protein concentrate, and immune-supporting compounds like lactoferrin), the company is already expanding to other dairy products including cheese, yogurt, kefir, and colostrum 1 3 .
Preservation of immune-supporting compounds that may help prevent allergies and asthma
Lower energy consumption and reduced environmental footprint compared to thermal methods
Clinical trials exploring benefits for elderly vaccine response, childhood asthma, and more
FDA-approved for powdered dairy ingredients including whey protein concentrate and milk protein concentrate 1
Development underway for cheese, yogurt, kefir, and colostrum applications 1 3
Trials exploring benefits for elderly vaccine response, childhood asthma and allergy prevention, microbiome immune function, and athletic performance 3
Building on epidemiological evidence suggesting raw milk consumption protects children from developing asthma, hay fever, eczema, and food allergies 1
As we look ahead, UV treatment represents more than just a new processing method—it symbolizes a fundamental shift toward food technologies that respect both safety and nature's nutritional complexity. In the delicate balance between eliminating pathogens and preserving health-promoting compounds, ultraviolet light may well illuminate the path forward for the next generation of dairy products.
As one researcher aptly noted, "It's surprising to me how powerful milk is as a compound, but unfortunately, we have been destroying it for so long in the name of safety. It's exciting to be part of using milk now to improve human health" 1 . The future of dairy appears to be not in overcoming nature with technology, but in using sophisticated technology to better honor nature's design.