Coatings: Applying a food-grade coating or sealant to the surface of the meal box can create a barrier that repels water and oil.
Lamination: The bagasse material can be laminated with a thin layer of plastic or another material that provides a water- and oil-resistant surface.
Additives: Incorporating additives during the manufacturing process can improve the water and oil resistance of the bagasse. These additives must be food-safe and should not compromise the biodegradability of the meal box.
Surface Treatment: Techniques such as plasma treatment or corona treatment can modify the surface properties of the bagasse, making it less permeable to liquids.
Wax or Resin Impregnation: Impregnating the bagasse with wax or a food-safe resin can provide a protective layer that prevents water and oil absorption.
Pulp Modification: Modifying the pulp during the manufacturing process to increase its density or by using chemical treatments can enhance its natural resistance to liquids.
Design: The design of the meal box can also influence its water and oil resistance. For example, incorporating a raised lip or a flange can help prevent spills.
Composting: Even with these treatments, sugarcane bagasse meal boxes are still designed to be compostable, so any treatments applied must be compatible with composting processes.
It’s important to note that while these methods can improve the water and oil resistance of sugarcane bagasse meal boxes, they may not make them entirely waterproof or oilproof like some plastic containers. The treatments are typically designed to be sufficient for single-use applications while maintaining the eco-friendly characteristics of the product.