Protein food freshness paper sensor as well as preparation method and application thereof

The invention discloses a protein food freshness paper sensor as well as a preparation method and application thereof, and belongs to the technical field of biochemical sensing. The preparation method comprises the following steps: S1, preparing the fluorescent test paper; and S2, preparing the double-response paper sensor. In the step S1, the test paper is formed by copolymerizing and modifying the surface of filter paper through a fluorescent reagent and a silane coupling agent; in the step S2, the paper sensor is prepared by adsorbing a pH-sensitive color-changing compound by the test paper in the step S1. The paper sensor can be used for real-time monitoring of the freshness of the protein food, the test paper synchronously shows obvious apparent color and fluorescence changes when the food goes bad, the response is rapid, the change of sensing signals is irreversible, the anti-interference capability to other volatile matters is high, and the accuracy and reliability of a food freshness monitoring result