Manufacturing method of packing material capable of sensing food freshness

The invention discloses a manufacturing method of a packing material capable of sensing food freshness, which comprises the steps as follows: depending on the types of foods to select different gas-sensitive color change materials of which the colors can change along with odors sent out due to the deterioration of the foods; selecting a food-grade freshness preservation film or food-grade acid-free paper as a base material for food packing; dissolving different gas-sensitive color change materials in the corresponding organic solvents to prepare different gas-sensitive color change material solutions with the concentration of 0.1-0.5 mol/L; adding 5 mol/L stabilizing agents in the different gas-sensitive color change material solutions; and uniformly spraying obtained products onto the center of substrate material for food packing at certain intervals in an ink and spot spraying manner so as to form a group of gas-sensitive color change material point arrays or a row of gas-sensitive color change material points. The packing material manufactured with the method not only has the same freshness preservation function as an ordinary packing material, but also can sense the freshness degree and quality of foods and can be used in the packing of medicines and cosmetics and as well as anti-counterfeit packing of chemical industry.