What’s in your coffee? Live testing at LLL ’26

What if you forget your reference samples for a live demo?

Grab a coffee, of course.

At London Lab Live 2026, coffee wasn’t just fuelling the conversations, it became the experiment. We tested freshly brewed coffee with the Lumero particle size analyser to showcase just how flexible the system really is.

And the results? Much more interesting than you might expect from your morning drink.

Our live demo highlighted the wide concentration range Lumero can handle, from transparent to fully opaque samples. Even coloured, light-absorbing particles, typically a challenge for many techniques, were measured without issue.    Our eye-catching display of orange / brown solutions was made from Nescafe original decaffeinated diluted over a range of concentrations. Naturally, this became the perfect starting point for the first experiment. Let’s take a closer look.

What did Lumero revealed?

Instant coffee

The most concentrated solution (around 10-20% of the normal concentration for drinking) was loaded straight into the Lumero and was found to have a mean particle radius of 669nm and polydispersity index of 0.18.

Instant coffee
Uniform particle distribution observed in concentrated instant coffee, indicating relatively low polydispersity compared to fresh milk-based systems.

Fresh grounded coffee

Now compare that to a skinny flat white (espresso plus skimmed milk) bought from Costa coffee during the event, and things get even more interesting.

Complex bimodal distribution observed in milk-based coffee, with nano-scale casein micelles contributing a distinct secondary population.

This time the equivalent peak has reduced to a mean particle radius of 402nm, , with a significantly larger polydispersity of 0.27.    However, a second, much tighter peak appears at a smaller particle size – with a mean particle radius of 82 nm.

This smaller size is consistent with casein micelles, naturally occurring protein structures in milk which are the dominant remaining population after skimming, and are typically in the 25–100 nm radius range. Clearly, even without knowledge of the refractive indices, the milk contributes as much to the drink as the coffee – which any coffee drinker can attest to. Suddenly, that simple coffee order becomes a neat demonstration of nanoscale biology in action.

So why is this exciting?

Because this quick, improvised demo actually highlights some powerful capabilities:

  1. Nano-scale detection in complex samples
    Lumero can resolve small structures like casein micelles, even in the presence of larger, coloured particles.
  2. Broad concentration range
    From clear to opaque, even coloured, real-world solutions can be measured reliably.
  3. Ease of use
    Measurements are simple enough to be performed by non-experts, using portable equipment, no perfectly prepared samples required. There was no complex protocol development or special preprocessing required – all of these measurements were performed on the spot at what was already a very busy conference.

Nescafe original vs skinny flat white coffee.
Picture of Dr Tiffany Wood, MPhys, PhD

Dr Tiffany Wood, MPhys, PhD

Co‑Founder & CEO, Dyneval

Dr. Tiffany Wood is an expert in soft matter physics and microfluidics with 20+ years of experience in complex fluid dynamics. As Co‑Founder of Dyneval, she specialises in translating advanced physics into real‑time diagnostic technologies for biotech, pharma, and agriculture.

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