Development of a triple channel colorimetric paper sensor array based on quantum dots: A robust tool for process monitoring and quality control of basic liquors of Baijiu

Process analysis of basic liquors of Baijiu is a great challenge in industry due to the complexity fermentation processes and tiny product differentiation of basic liquors. In this work, a new triple channel colorimetric paper sensor array based on quantum dots (QDs) with three color-emission was established for the rapid process monitoring of basic liquors of Baijiu. The fluorescence of QDs can be quenched to varying degrees by the ingredients in basic liquors with different production processes, batches and qualities. Through analyzing color change (RGB value) of QDs under the UV lamp, all the corresponding information that represents basic liquors of Baijiu was extracted and further processed by principal component analysis and partial least squares discriminant analysis. By utilizing this colorimetric paper sensor array, all the production processes, batches and qualities of basic liquors can be monitored quickly and accurately with a recognition rate of 100%. What’s more, this paper sensor array required neither special modification nor complex sample preparation and can implement rapid and precise visualization analysis by the naked eye with the aid of a portable UV lamp using only a simple device and small amount of sample, showing its potential applications in the food industry.