ProPak Asia Highlight: Smart Food Label senses protein freshness with biogenic amines | 21-08-2024 |

A research group based at City University of Hong Kong focused on designing and synthesizing specific molecule sensors, has developed a low cost Smart Label capable of sensing the freshness of proteins such as cooked or uncooked meat and seafood using the biogenic amines generated by spoiling foods. The group developed a green testing paper, which could be put in pre-packaged food, or embedded in the wrapping film, which informs customers whether the food is spoiled or not, helping to significantly reduce food waste and food shortages, explained Giselle Chow of Zenxtag in her lecture.

The group successfully applied for seed funding to develop the technology commercially via the HK Tech 300 scheme. With a $HKD 200,000 grant ZenxTag was established in 2022. The company has designed a new type of monitoring tool with a specific sensing molecule and turned it into a green-coloured ink. Now it has developed a smart food label using green testing paper, incorporating back sheets of the label with a hole and colour scale. Internal QC staff or customers can compare the colour of the testing paper with the colour scale to determine if the food is fresh or spoiled. If the colour of the testing paper is green, the food is fresh. However, if the food is spoiled, the colour of the testing paper will turn orange.

Initially the technology was tested in 2018, as a hydrogel, with a green molecular sensor adsorbed inside, but this proved expensive and not environmentally friendly. Following further development the latest generation smart food label can detect biogenic amine gas from outside of the label and is equipped with an IoT system. In addition to providing information on freshness the label can also provide promotional and stocking information.

Many start-up companies have developed similar products for detecting biogenic amines, says Zenxtag, but they all use acid-base reactions for detection. These testing technologies can be affected by numerous factors during food production, such as acid additives or other chemicals that can affect the pH value of the pre-packaged food. 

ZenxTag's chemo sensitive ink is prepared with a complex molecular sensor that specifically targets the detection of biogenic amines, a well-known biomarker for detecting food freshness. Also it has tested the precision and accuracy of the chemical ink and compared it to traditional testing results. These advantages make the product stand out from others used in food quality monitoring, it claims.

Initially the smart food label will be deployed in B2B, to improve internal quality control systems in the industry. After the concept of smart food labels is popularized and promoted to the public it hopes to put the label product in the retail market.

Having finished the prototype the company is now ready to design the pilot production line. But Hong Kong set up costs are high, so it is looking to set up the line in South Asia. In effect the seed funding has enabled Zenxtag to reboot the project. Help also came via the tag technology winning a gold medal at the Geneva International Invention Exhibition in 2023.

Having got funding support the next step is finding a business partner to help build up a pilot production line in South Asia. In 2025 it will launch smart food labels for internal quality control in the food production and distribution industries. By 2026/7 it hopes to upgrade the smart food label  for retail use and develop a cool-chain logistic system.

AIPIA and AWA Smart Packaging World Congress Amsterdam