BioBag kitchen waste bags are primarily used for the collection of food scraps and other waste for home or community composting. Our popular BioBag 3 gallon size is designed to fit most kitchen countertop composting pails. BioBag 3 Gallon Food Waste Bags are primarily used for the collection of food scraps and other waste for home or community composting. Our popular BioBag 3 gallon size is designed to fit most kitchen countertop composting pails. The BioBag contains no polyethylene.