The freshness of packaged foods is estimated by the “use-by” date that appears on the packaging. This date, however, does not reflect the actual state of freshness of the consumable, because it is dependent on, in addition to formulation and packaging, the storage and processing conditions. “Use-by” dates, which are approximations, lead to substantial food waste by consumers as they do not provide information concerning the actual freshness of the product in real-time.
The Guder Research Group at Imperial College has recently developed a new sensor technology (Barandun et. al., ACS Sens. 2019) that can measure food freshness in real-time and could replace the “use-by” dates to prolong shelf-life, reduce food waste and foodborne illnesses caused by spoiled foods. The sensors are printed paper-based electronic labels, that are applied to the packaging containing the fresh product, and detect gases released due to microbial spoilage of food in real-time. The sensors can be interrogated using near-field communication (NFC) enabled smartphones wirelessly and do not require additional hardware.
The project involves continued engineering development and testing to study how the technology would be used and its potential impact on food waste.