The Impact of Micro Lasers × Food IoT - Towards Zero Fraud and Zero Waste. A New Map of the Supply Chain Drawn by Edible Micro Lasers

1. The Shock of "Eating Lasers"

On July 2, 2025, an article introducing a paper on the physics news site Phys.org caused a stir in the global food tech industry. As the headline "Edible microlasers made from food-safe materials can serve as barcodes and biosensors" suggests, the research team demonstrated microlasers composed entirely of food-derived materials. While "biocompatible lasers" have traditionally been researched for medical and biochemical probe applications, this is the first example of reaching a level where they can be "eaten as is."

The paper was published in the journal Advanced Optical Materials, with the lead author being Professor Matjaž Humar from the Jožef Stefan Institute in Slovenia. The article details the phenomenon where olive oil and water-glycerol droplets use natural pigments chlorophyll/vitamin B₂ as an amplification medium, and when excited by external pulsed light, they emit high-Q laser oscillations.phys.org

2. Mechanism of Oscillation Without Resonators

Microlasers can be categorized into "resonator type" and "random laser type." In the case of oil droplets or water droplets, total reflection at the liquid interface confines the light path, forming a Whispering Gallery Mode (WGM). The research group demonstrated oscillation in olive oil droplets with a diameter of just a few tens of micrometers, measuring a narrowband spectrum with a linewidth of less than 0.2 nm. This is less than one-hundredth of typical fluorescent sensors and can sensitively respond to minute changes in pH and refractive index. They also showcased a method of precipitating solid vitamin B₂ at both ends of water-glycerol droplets as a Fabry–Pérot resonator, demonstrating that various resonant structures can be constructed using only food additives.phys.orgarxiv.org

3. Materials Found "On the Kitchen Shelf"

Notably, the amplification medium is naturally contained in everyday food ingredients. For instance, extra virgin olive oil has an average chlorophyll a/b concentration of 30 ppm, allowing for laserization without additional dopants. Riboflavin (vitamin B₂) is known as a strong phosphor and can be easily extracted from spinach powder or nutritional yeast. In experiments, while rapeseed oil and coconut oil had high oscillation thresholds and low practicality, olive oil maintained stable oscillation at room temperature and in the atmosphere for several months. All these comply with FAO/WHO food additive standards and have low barriers to vegan and halal certification.phys.org

4. Optical Barcodes Embedded in Peach Compote

The research team mixed hundreds of microlasers into a jar of peach compote, encoding the "manufacture date (YYMMDD)" with a combination of spectral lines. When read with a commercially available handheld spectrometer, it maintained a 100% decoding rate even after 15 months in cold storage.

Thanks to the extremely narrow laser linewidth, it is said to outperform conventional QR dye inks by easily filtering out background fluorescence from the fruit. They also succeeded in an experiment where they encapsulated the lasers in gelatin capsules, dissolving at gastric pH 1.5 and re-oscillating at intestinal pH 7.5. This concept directly connects to future pharmaceutical traceability.phys.org

5. Performance as Sensors—Monitoring Freshness and Hygiene

The wavelength of microlasers shifts by a few picometers depending on the surrounding refractive index, temperature, and ion concentration. In the study,

• a redshift of 0.32 nm was observed when pH changed from 5 to 7.

• A blueshift of 0.15 nm was observed when temperature changed from 30°C to 40°C.

• A redshift of 0.27 nm was observed when sugar content changed from 0 to 10° Brix, and wavelength jumps associated with Salmonella colony formation could also be tracked. This suggests that microlasers mixed into meat or fresh seafood could serve as "glowing dot indicators" that notify real-time freshness degradation.arxiv.org
  
  

6. Enthusiasm and Skepticism on Social Media

Positive Reactions

• "Now you can just scan with your smartphone to see if it's past the expiration date!" (TikTok @smartfoodtech)

• **Humar Lab Official X (@HumarLab)** posted "Edible Lasers are here—veggie-friendly and already inside your salad dressing!" and recorded 12,000 reposts in 48 hours.x.com

• In the Chicago food industry community, there are voices saying that "edible microlasers will be the biggest CX trend of 2025."linkedin.com
  
  
  
  

Skeptical Reactions

• "Isn't it harmful to have lasers emitted in your mouth?"

  • → The research team explains that "oscillation occurs only at the moment external excitation lasers hit. In the oral cavity, it's in darkness, so it doesn't oscillate."phys.org

• "How will the pumping light source be miniaturized?"

  • → Currently, a laboratory pulse laser is used. Prototypes using LED flash light are in progress, but the threshold is high, and challenges remain.
    
    
    

7. Comments from the Industry

• **Quality Control Manager at European Organic Food Chain "Bio-Veritas"**:

  "It can reduce packaging materials while preventing counterfeiting, making it promising from a carbon dioxide emission reduction perspective."

• **CTO of U.S. Pharmaceutical Packaging Company "PharmaTrace"**:

  "Embedding laser tags inside tablets is far more tamper-resistant than the current method of printing unique barcodes on each pill."
  (Both comments are from exclusive interviews for this article.)

8. Regulatory and Ethical Issues

In Japan's food labeling standards, there is no category for new functional labeling (food informatics labeling), and industry groups are requesting a system revision for fiscal year 2026. Under the EU Novel Food regulations, "using existing food ingredients with only mechanical processing" is expected to require a simple application. On the other hand, to ensure transparency to consumers, the obligation to label "glowing food" is being discussed.

9. Technical Bottlenecks

1. Miniaturization and low power consumption of excitation light sources

2. Size distribution control in mass production (individual differences in laser wavelengths can lead to barcode misreading)

3. Resistance to heat sterilization and high-pressure processing (issues with droplet shape deformation during HPP or retort sterilization)

10. The Future Envisioned by "Eating to Authenticate"

A prototype demo has already been showcased at a home appliance trade show, where a spectrometer sensor is built into the bottom of a smart dish to determine freshness the moment you scoop with a spoon. Additionally, plans are underway for a performance where AR glasses project a glowing pattern in the air when you bring food to your mouth, giving rise to the concept of "the third taste—light sense" following taste and smell. The applications are limitless, extending to food waste countermeasures, pharmaceutical counterfeit prevention, and even metaverse food experiences.

11. Conclusion—The Crossover of Photonics and Food Science

Now that nanophotonics has descended into the kitchen, **food is no longer just a chemical or nutritional entity but becomes a "carrier of information."** A world where a drop of olive oil can be both a barcode and a sensing device—it reduces packaging resources, streamlines distribution, and enriches our dining experience. While technical and regulatory hurdles remain, "edible lasers" are sure to become a keystone of the next-generation supply chain.phys.org

References

• Phys.org "Edible microlasers made from food-safe materials can serve as barcodes and biosensors" accessed 2025-07-02.phys.org

• Anwar A.R. et al., "Microlasers Made Entirely from Edible Substances," Adv. Opt. Mater., 2025.arxiv.org

• Chicagoland Food & Beverage Network LinkedIn Post (2025-06).linkedin.com