UV-C Is Not New. What’s New Is Where It Finally Works.

For decades, UV-C disinfection has been quietly protecting public health. Municipal water plants, bottled water lines, and point-of-use systems around the world rely on UV-C to inactivate pathogens—without chemicals, without heat, and without residues.

Yet for just as long, UV-C stopped at one boundary: clear water.

Milk, juices, sugar syrups, plant-based beverages, and other opaque liquids were considered out of reach. Not because UV-C doesn’t work—but because light cannot penetrate these fluids the way it penetrates water.

That limitation has now been fundamentally solved.

This is the story of how UV-C evolved from water treatment into what may become the most influential non-thermal technology in liquid food processing—and why FloUV is at the center of that shift.

How UV-C Actually Inactivates Microorganisms (The Science)

UV-C light (200–280 nm, typically 254 nm) inactivates microorganisms by direct photochemical damage to nucleic acids.

At the molecular level:

• UV-C photons are absorbed by DNA and RNA bases

• This causes formation of cyclobutane pyrimidine dimers (CPDs)
  – most commonly thymine–thymine dimers

• These dimers distort the nucleic acid helix

• Replication and transcription are blocked

• Cells lose the ability to reproduce → microbial inactivation

This mechanism is:

• Non-thermal

• Non-chemical

• Effective against bacteria, viruses, spores, and protozoa

This same mechanism has been trusted in water treatment for over 40 years.

So why didn’t it move into food?

Why UV-C Worked in Water — and Failed in Milk

Water is optically simple:

• UV transmittance (UVT): >90%

• Minimal absorption

• Minimal scattering

• Pathogens are fully exposed to photons

Milk and liquid foods are optically complex:

• Proteins absorb UV

• Fat globules scatter light

• Colloids create shadowing

• Photon penetration drops to <1 mm

In conventional UV systems:

• Fluid near the wall is over-exposed

• Fluid in the core is under-exposed

• Increasing lamp power only worsens quality damage

• Safety becomes non-uniform and unverifiable

This is why straight-tube and thin-film UV reactors—originally designed for water—could never guarantee safety in opaque liquids.

Water UV Reactor Design vs. FloUV Reactor Design

Water UV systems are built around a simple assumption:
“If the light reaches the liquid, the job is done.”

That assumption breaks down immediately in food.

Conventional Water UV Design

• Straight or annular tubes

• Minimal secondary flow

• Laminar or weakly turbulent regimes

• UV dose calculated from lamp output

• Dose delivery occurs mainly near the surface

FloUV System Design (Fundamentally Different)

• Serpentine and helical flow pathways

• Engineered Dean vortices and secondary circulation

• Continuous radial and axial fluid exchange

• Every fluid element is repeatedly brought to the illuminated FEP tubing surface

• UV dose is delivered, not assumed

Instead of asking “How strong is the lamp?”
FloUV asks “How many times did each micro-volume see the light?”

This distinction changes everything.

Why FEP Tubing + Flow Physics Matters

In FloUV systems:

• UV-C lamps irradiate the inner surface of UV-transparent FEP tubing

• Photon intensity is highest at the tubing wall

• Curvature-induced centrifugal forces generate counter-rotating vortices

• These vortices continuously:

• Pull fluid from the dark core to the bright boundary

• Push exposed fluid back into the bulk

The result:

• Shadowing is continuously broken

• Over-exposure zones collapse

• Under-treated cores disappear

• Dose distribution becomes narrow and predictable

This is the missing physics that water UV never needed—and food UV always did

From “Lamp Power” to Delivered Dose: REF & PEF

In water, UV dose can be estimated.

In opaque liquids, it must be measured.

FloUV uses Reduction Equivalent Fluence (REF):

• Derived from biodosimetry

• Based on actual microbial inactivation

• Accounts for absorption, scattering, flow, and residence time

REF is then translated into Pasteurization-Equivalent Fluence (PEF):

• Directly comparable to thermal pasteurization benchmarks

• Bridges non-thermal UV processing with regulatory frameworks

This is not theoretical modeling.
It is experimentally validated dose delivery in real fluids under real flow conditions

Why This Unlocks a New Era for Processors

For the first time, UV-C can now be applied to:

• Whole milk and skim milk

• Whey and native protein streams

• Sugar syrups

• Juices with pulp

• Plant-based beverages

• Brines and functional liquids

And it does so while:

• Preserving lactoferrin, IgA, vitamins

• Avoiding cooked flavors

• Reducing energy use dramatically

• Enabling raw-like but safe product concepts

This is not incremental improvement.
This is a process-level shift.

UV-C Was Always Powerful. It Just Needed the Right Reactor.

UV-C has protected water for decades.

FloUV is the first company to:

• Re-engineer UV-C around fluid dynamics

• Validate dose in opaque and viscous liquids

• Transform UV-C from a water technology into a food-grade processing platform

What thermal pasteurization did for safety,
FloUV is now doing for quality-first, non-thermal processing.

The future of liquid food processing is no longer about adding heat.

It’s about delivering light—precisely, uniformly, and scientifically.