Wireless charging flexible in-situ optical sensing for food monitoring

Food safety is an important public health issue, real-time monitoring and identification of food freshness is essential to ensure food quality and consumer health. This study presents a wireless charging flexible in-situ optical sensing system (FIOS). FIOS integrates visible (VIS)/near-infrared (NIR) spectral sensors, electronic components, and microcontrollers into flexible circuits by flexible electronic technology, and obtains energy through wireless charging to solve the problem of battery replacement and frequent charging of electronic systems. FIOS exhibits excellent flexibility and bendability which can be attached well to the surface of the food for efficient, accurate, non-destructive, and in-situ monitoring. A prediction model between food quality and spectral data was established by chemometrics to achieve accurate prediction of food quality. It can obtain the spectral information of the food in real-time and transmit the data wirelessly to a cloud platform, which enables the visualization of food quality and facilitates quality traceability. FIOS is characterized by simple craft, low cost, and real-time monitoring, and can be widely deployed as an Internet of Things (IoT) node in food transportation, storage, and sales to improve the transparency of food at all stages and ensure the quality and safety of food. The FIOS has the advantages of portable and non-destructive monitoring, which improves the accuracy of food quality monitoring and provides a new technological program in the field of food quality monitoring. It is expected to promote the development of food quality and safety monitoring in the future and provide consumers with a more reliable guarantee of food quality.