Spoilage Marker Dosimetric Tool

ZenxTag Technology Limited is a Hong Kong-based food technology company specialising in real-time food freshness monitoring solutions. The company develops low-cost, disposable smart labels that use proprietary chemosensing technology to detect key biomarkers of food spoilage and ripening, helping reduce waste and improve food safety across the supply chain.

The Problem

Approximately 1.3 billion tonnes of food are wasted globally every year. In Hong Kong, food waste accounts for around 30% of solid waste (roughly 3,000 tonnes daily). Much of this waste occurs because products are discarded according to fixed expiry dates rather than their actual condition. Traditional methods lack practical, affordable tools for real-time freshness assessment, particularly for high-protein foods and fruits whose quality changes rapidly due to bacterial activity, ethylene gas, temperature fluctuations, and other factors.

Core Technology and Products

ZenxTag’s flagship innovation is the Spoilage Marker Dosimetric Tool (SMDT) — a paper-based or pad-based label coated with specialised chemosensing inks. These inks react to specific volatile compounds released during food degradation or ripening and produce a clear visual colour change that can be read by the naked eye without any equipment.

The main sensing technologies include:

• Biogenic amine sensing — Detects compounds released during bacterial breakdown of proteins. Suitable for meat, poultry, and seafood. The pad starts colourless (fresh) and turns dark blue when spoilage markers appear.

• Mercaptan (thiol) sensing — Targets volatile compounds associated with spoilage or ripening in high-protein foods and certain fruits such as durian. A distinct colour shift (typically brown to dark) indicates the product should be used or discarded.

• Ethylene sensing — Monitors the natural plant hormone that accelerates fruit ripening. Yellow indicates optimal condition; a shift toward purple signals over-ripening.

Application is simple: For packaged food, a small opening is made in the film and the label is affixed over it. For unpackaged or opened food, the sensor is placed in direct contact. Results are typically readable after about 30 minutes. The unit cost is kept below USD 1, making the solution practical for large-scale commercial use.

Target Users and Business Focus

ZenxTag primarily serves food manufacturers, processors, hospitality operators, catering services, and high-end retailers. Future expansion includes institutional users (such as school and factory canteens) and household consumers. The business model centres on direct sales of the labels, supported by pilot programmes and strategic partnerships.

Intellectual Property and Development

The company has secured patent protection for its biogenic amine sensing technology in the United States and China, filed design patents for sensing devices, and registered its trademark. The underlying research originated from academic work on molecular sensing led by co-founder Professor Lam Hon Wah. Development has progressed from laboratory validation through prototyping, environmental testing, pilot production readiness, and application-specific versions (including specialised labels for durian and berries).

Team

• Giselle Chow Tsz Wing, Director and Co-founder, leads commercialisation, product development, and stakeholder engagement. She holds a BSc in Chemistry from City University of Hong Kong and has research experience in molecular sensing.

• Professor Lam Hon Wah, Co-founder, is a molecular sensing expert with extensive academic and industry networks. He is a key inventor of the biogenic amine sensing approach and continues to guide technical development.

The company has received support from the HK Tech 300 programme, Hong Kong Science Park, City University of Hong Kong, and related grants, and has earned recognition in multiple innovation competitions and exhibitions.

Vision

ZenxTag aims to transform complex chemistry into an everyday visual tool that enables better decisions about food quality. By focusing on actual biomarkers rather than time or temperature alone, the company provides a practical, affordable way to reduce food waste, protect brand reputation, and support more sustainable food systems.