Sensors and smart food packaging for supply chains: Bridging expiration dates and actual perishability

The food supply chain is undergoing critical changes to minimize environmental hazards, such as those associated with packaging, and reduce food waste and loss. One of the critical components of the latter is associated with the high variance in the perishability of individual foodstuffs. Herein, we review the state of the art in smart sensor systems and emphasize the critical role they could play in addressing the mismatch between “batch” based expiry dates and individual food products’ time-dependent responses to spoilage. Following a brief overview of food shelf life and associated legislation, a subsequent section summarizes the development of sensors for monitoring food spoilage. Moreover, this review encompasses sensors for spoilage detection and for monitoring storage quality, including those for measuring gas, pH, humidity, and temperature. A detailed study of their designs, selectivity, range, limit of detection, specific analyte molecules, and active materials is presented, with consideration of the state of the art. Fabrication techniques for sensors are then presented, and the manuscript concludes with an overview of emerging developments and the remaining challenges for their efficient implementation across the food sector. Overall, the article highlights an emerging opportunity for sensor science to have a global impact on a more resilient, safe, and sustainable food supply chain.