Wondering if the chicken in your fridge that is just past its best-before date can still be eaten? In the near future, an innovative smart food label could tell you whether you need to dispose of the item or if you can safely consume it.
This clever label was conceived by start-up ZenxTag, made up of a team of researchers from City University of Hong Kong (CityU). The paper-based smart food label contains CityU-patented chemosensitive ink that reacts with biogenic amine, a well-known biomarker for detecting freshness in protein-rich items such as meat and seafood.
A small hole is made in the wrap of pre-packaged food and the label is placed on top of this hole. When the food degrades and generates biogenic amine gas, it will react with the chemosensing agent and cause it to change colour from green to orange, indicating that the food has spoiled.
Ensuring food safety and curbing wastage
ZenxTag is one of the many start-ups incubated by HK Tech 300, CityU’s large-scale flagship innovation and entrepreneurship programme. HK Tech 300 aims to encourage aspiring entrepreneurs to launch start-ups by providing training, networking, seed funding and angel fund investment, as well as opportunities for further financial support.
It was also launched to translate CityU’s research achievements and intellectual property into practical applications to benefit society, and the university is keen to create 300 start-ups within three years.
Although detecting biogenic amine to gauge food freshness may not be anything new, ZenxTag’s invention stands out for its novel chemosensing technology.
“Other start-ups have developed similar products, but these use acid-based reactions for detection. These technologies can be affected by numerous factors, such as meat products prepared with acid additives or other chemicals, which can affect the pH value of the pre-packaged food,” says Ms Giselle Chow, director of ZenxTag and an alumna of CityU.
While ZenxTag initially manufactured the smart food label in the form of a hydrogel, the team later pivoted to a more environmentally friendly paper-based design. The researchers hope this can help make a dent in addressing the pressing global problem of food waste by offering a more precise and accurate assessment of food freshness than best-before dates, which are generally used as guidelines.
“It can inform customers whether the food is spoiled, potentially extending or replacing the expiration date. This could also significantly reduce food waste and improve food-shortage issues, while decreasing environmental pollution,” says Ms Chow.
Super-strength, eco-friendly bamboo
Another start-up nurtured through HK Tech 300 is Super Bamboo, a green materials company on a mission to save the planet. Their signature invention is an advanced augmented bamboo material that is three times tougher than regular bamboo and even stronger than industrial steel and titanium alloys.
“Our CityU-patented technology is a breakthrough manufacturing process. We believe that it is the first in the world to use zero glue, which is typically used to turn raw bamboo that is round in shape into engineered bamboo that is rectangular and more usable,” says Mr Andy Ong, CEO of Super Bamboo and an alumnus of CityU. “This introduces problems including additional embodied carbon, the emission of toxic formaldehyde and difficulty with recycling and biodegradation.”
