Biodegradable is not enough – why compostable is the future

Here at Kelpi, we’ve focused on developing bioplastic packaging that is marine-safe and home-compostable. So what does that mean?  

Bioplastics have been derived from renewable sources like seaweed, or plants or trees – in short from any agricultural or marine materials. Unlike most current plastics that are derived from non-renewables like fossil fuels (typically oil).

Compostable bioplastics break down into water, CO2 and biomass/inorganic compounds – just as leaves or potato peelings would do. To be classed as compostable, plastic must become indistinguishable in compost, with no toxins left behind, within six months.

Biodegradable is different. It only means that in the right conditions, it will eventually break down. There’s no time limit – it could take hundreds of years to biodegrade - and it can leave behind toxic residue. So that’s how some plastics from oil can still be described as biodegradable.

Not all bioplastics are even biodegradable, let alone compostable. And even then the term compostable can mean different things. Industrial composting or anaerobic digestion facilities – the kind that your local authority might use for food or garden waste – operate at a much higher temperature than garden composting. So a wider range of compostable bioplastics can be broken down there than at home. 

Kelpi’s home-compostable bioplastic packaging can go into the home compost, for those that have access to one. Or if you don’t, then you can put it into the food waste bin safe in the knowledge that it can be composted in an industrial facility even faster.

You could call it sustainable or circular packaging – Kelpi bioplastic going to nourish the soil once it’s fulfilled its packaging purpose. We call it home-compostable. But it doesn’t rely on recycling (and only 9% of the world’s plastic gets recycled). And doesn’t end up in landfill or being incinerated.