Recent advances in colorimetric sensors

Recently, due to growing consumer concern about food safety, innovative packaging that indicates the quality status of food through color changes has attracted great interest. Rich protein content and high water activity foods are prone to spoilage during distribution, transportation, and storage, increasing the urgency of spoilage/freshness assessment. Fabrication of novel materials such as colorimetric sensors/indicators has gained great interest for monitoring food safety and quality due to their sensitivity, cost-effectiveness, and simplicity. This chapter aims to provide an update on the current innovative methodologies for designing and fabricating food colorimetric sensors such as electrospun nanofibers, electrochemical writing, inkjet printing, sol-gel techniques, and paper-based colorimetric sensors. Besides, the recent advances in colorimetric sensor construction, sensing platforms with the aid of a smartphone, and mini-program for assessing food safety and quality were documented. Finally, the future trends in the development of food colorimetric sensors have also been discussed.