Coffee capsules made from compostable bioplastic are the most sustainable

Coffee capsules made from compostable bioplastic are more sustainable than those made from aluminium or plastic. This is shown in a study from the Dutch research centre Wageningen Food & Biobased Research, a part of Wageningen University & Research. As reported by Polimerica, the study showed that capsules produced by an Italian company through the thermoforming of polylactic acid (PLA) are the best, when compared with capsules made from aluminium and plastic (HDPE and PP), both in terms of greenhouse gases and the circularity of materials.

The study examined different end-of-life scenarios, including industrial composting, mechanical recycling, incineration and landfill. When calculating the overall impact, the study also accounted for the fate of the spent coffee grounds within these capsules. The study assessed different combinations of materials and disposal methods, estimating their global warming potential in CO₂ equivalent over a period of 100 years, as well as their Material Circularity Indicator (MCI). This indicator, developed by the Ellen MacArthur Foundation, is one of the most comprehensive tools for measuring the circularity of materials and offers scientifically based insights for guiding sustainable material choices.

Coffee capsules made from compostable bioplastic had an MCI of 100% (fully circular), when the capsules are composted. Aluminium capsules are second-best, provided they are collected separately (mono-collection): the aluminium is then recycled and the coffee composted. However, even under these conditions the MCI is lower, at around 60%. In last place are capsules made from conventional fossil-based plastics, as neither the capsules nor the spent coffee grounds are recycled (MCI below 50%).

The following end-of-life scenarios were considered: industrial composting (only for compostable capsules), recycling via lightweight packaging waste collection, incineration with energy recovery, landfill with energy recovery, and mono-collection (only for aluminium capsules).