Food safety test uses quantum mechanical effects

08 Dec 2022

In project QSPEC, LZH, Toptica, and partners developing rapid check on ingredients, origin.

In a newly-announced photonics-based food safety project, Laser Center Hannover (LZH), Germany, and partners are working together to develop a new analysis method that uses quantum mechanical effects to test food for ingredients and origin “more cost-effectively”.

The project, called QSPEC, also involves companies AMO and Toptica, and research organizations University of Hannover, and DIL, the German Institute of Food Technology. Their aim is to develop an alternative quantum-based spectroscopy test that is more compact, less expensive and highly sensitive than conventional methods.

The project’s launch statement said, “Fraud in the labeling of food ingredients cannot only cause economic damage but can also lead to health risks. Laboratories therefore use authenticity tests to determine whether the declared geographical origin of foods is correct, whether certain ingredients such as palm oil have actually been omitted, or whether no others have been added.

“To date, nuclear magnetic resonance spectroscopies are being used for these analyses. NMR spectroscopy makes it possible to clearly identify almost any organic substance in a given sample. However, the analyses are very expensive, as the systems are large, complex, and cost several million euros.”

Contactless measurement – by quanta

In QSPEC, which is funded by the German Federal Ministry of Education and Research (BMBF), the focus is on quantum-based spectroscopy. Dr. Stephan Suckow, Head of the Nanophotonics Group at Aachen-based research SME AMO, who is also collaborative coordinator of the QSPEC project.

Dr Suckow commented, “In the first step, an entangled photon pair consisting of a long-wavelength and a short-wavelength photon is generated. The long-wavelength photon interacts with the sample, changing its phase, for example. This manipulated photon pair is then fed into another process, in which yet another photon pair is generated.”

“The information contained in the pair is transformed by quantum interference, so it eventually becomes readable simply by the count rate of the short-wavelength photons. The short-wavelength photons act as carriers of information and can be measured particularly well with current technology. The bandwidth of the photon pairs makes it possible to resolve the sample spectrally.

Dr. Suckow concluded, “The resulting spectra of the individual food samples are like fingerprints in this regard. We can then compare these fingerprints with other reference samples and thus draw conclusions about ingredients and geographical characteristics.”

New tools, new capabilities

In order to generate the quantum frequency combs, novel laser beam sources are needed, which is where LZH and Toptica are involved. AMO will use nanolithographic methods to create chips that accommodate the necessary technology in the smallest possible space.

And AMOtronics will contribute the ultrafast electronics required for detection. The Institute for Photonics at LUH will subsequently combine the individual components into a system so that the DIL can test the new method and build a reference library.

From the composition of the ingredients, the origin of foods such as olive oil, fruit juice, honey, and many others can be determined beyond doubt. Even the detection of contaminants at the lowest concentrations will be possible. This, say the project partners, “will form the basis for a new generation of analytical tools that allow comprehensive quality assurance in food production”.

Wafers with multiple, integrated, nanophotonic chips are necessary to develop a compact system for food analysis in the QPSPEC project. (Photo: AMO) Scientists at the LZH develop new laser beam sources the project QSPEC that can be used to generate quantum frequency combs. (Photo: LZH)