Visual food sensing: The state-of-the-art through strategies, tools, analytes, and actual applications

The emergence of food management highlights the need to monitor the quality, freshness and contaminants of food samples. Smart instruments are easy-to-use, portable, low-cost, real-time monitoring tools that operate on unprocessed samples, possibly integrated into commercial packaging. In the field of food detection, sensors that leverage visual output signals play a special role due to their customizable selectivity and sensitivity. Intelligent visual methods are highly sought after and growing in food science. Nowadays, the visual sensors used in food monitoring are varied and elaborate in terms of analytes, instruments and operation, so much so that they require a useful operational compendium. This comprehensive review aims to connect methods, strategies and applications of visual sensors for food industry and technology. The overview of the state of the art has been divided into three sections. The first introductory part is dedicated to operational strategies, a second part collects the various visual tools, a third part contains relevant cutting-edge articles. Our search criteria resulted in a representative selection of articles that reflect real-world food detection applications.