The main purpose of compostable products and packaging is to assist in the collection and diversion of food scraps to composting. This is why the Biodegradable Products Institute (BPI) only certifies products and packaging associated with organic waste diversion, with the main categories being foodservice products (cups, cutlery, straws, plates, bowls, takeout containers, etc.), food scrap collection bags and bin liners, and more recently items like coffee pods/capsules.

This has led to a widely held assumption that the only value of compostable products is as a tool for diversion, and that there is no inherent value to the products themselves. To investigate that assumption, the Foodservice Packaging Institute (FPI) and BPI commissioned an in-depth study of compostable packaging as a feedstock itself, compared to traditional inputs like yard trimmings. A field study was designed to answer the following question:

How does compostable foodservice packaging (FSP) compare with other conventional organic waste stream inputs (e.g. yard trimmings, straw, wood shavings, grass, food scraps, etc.) in its contribution to balancing targeted carbon to nitrogen (C:N) ratios, providing nutrients, and acting as a bulking agent in compost feedstocks?

For contribution of carbon, the short answer is that the organic carbon in products tested and certified to the ASTM standards must be converted into carbon dioxide (CO2), demonstrating that the carbon can be used as food for composting microbes, just like the conventional feedstocks a composter accepts. The non-organic carbon components in products are just as important, and lingo-cellulose that isn’t converted into CO2 results in the generation of finished compost to sell.