Handy sensor to enhance food safety

22 September 2018

A new food safety testing system has been developed by Professor Hon-Wah Lam of the City University of Hong Kong (Croucher Fellowship 1990 and Croucher Studentship 1986) to detect contaminants in food within several minutes.

The sensor, which can be operated via mobile phone apps, offers rapid and accurate measurements of harmful substances that might be present in seafood and meat. It is designed to detect histamine and formaldehyde, two commonly found contaminants in seafood and meat. Histamine is generated when bacteria grows in food and formaldehyde is an illegal additive used in seafood.

The sensor can detect food samples using a mobile phone.

Conventional tests for histamine and formaldehyde take about one day in a laboratory. With the new sensor connected to a mobile phone app, the test can be shortened to 10 to 25 minutes.

“Each contaminant has a specific bonding nature to a particular receptor. By using a chip that contains a specific receptor, the new sensor can indicate the existence and concentration of the target contaminant,” the team explained.

The handy sensor can detect up to 100 ppm for histamine, and 0.2ppm for formaldehyde. This level of detection complies with the standard set by international monitoring bodies such as the World Health Organization and the U.S. Food and Drug Administration.

This project also makes use of the technology of Internet of Things such as RFID labels to store the data of random food tests on the cloud for tracking and management purposes. With a prototype already in operation, the cost of is expected to fall.

The project has already attracted a great deal of commercial interest. It was selected as “Demonstrative Project of Innovative Development for Marine Economy under the China’s 13th five-year plan” and received a grant of RMB 20 million.

Dr Roy Vellaisamy, a colleague at the Department of Materials Science and Engineering at City University of Hong Kong foresees a wide adoption of the system in public and private sector. “The system can help government departments to monitor food quality and assist supermarkets in testing food on spot.”

Professor Michael Hon-Wah Lam received his PhD from the University of Hong Kong in 1990 and did his post-doctoral with the Nobel laureate (the late) Sir Geoffrey Wilkinson in the Johnson Matthey Laboratory of the Imperial College of Science, Technology & Medicine, UK. Before joining the City University of Hong Kong in 1994, he has also worked as a forensic scientist in the Government Laboratory of Hong Kong and as a water scientist in the Environmental Protection Department of Hong Kong.

To view Prof Lam's Croucher profile, please click here