In order to improve the oil and water resistance of the lunch box, wheat straw was used to produce the lunch box, while chitosan and beeswax served as raw materials for the oil- and water-resistant coating. The surface of the food box is coated by spraying. Firstly, a single chitosan solution is sprayed onto the surface of the wheat straw food box, and oil and water resistance tests are conducted. Subsequently, a composite oil and water resistant agent was prepared by adding beeswax to the chitosan solution. Optimization experiments were conducted on the dosage of the composite oil and water resistant agent from the perspectives of coating solution concentration and coating amount. The results showed that under the conditions of chitosan concentration of 2.0 wt%, beeswax solid content of 50 wt%, and coating amount of 2 g/m2, the oil resistance level of the food box could reach level 9 or above, and the water absorption rate decreased to 11.3%. The food box met the requirements for oil and water resistance, providing a promising green alternative to traditional plastic tableware.
Chen et al. (2026) studied this question.