About Compostable Coffee Bags
Freshly roasted coffee is a taste sensation. We at Corby Coffee are fortunate enough to enjoy it every day. Our passion has always been to share this experience with you.
When we at Corby Coffee first decided to offer our customers freshly roasted single origin coffee beans. It was our intention to source not only our beans responsibly but also our packaging.
We have found this very difficult to do.
For coffee to be kept fresh it needs to be protected from heat, sunlight, oxygen and other aromas which will depreciate the flavour contained within the freshly roasted coffee beans. We used to believe that this was best achieved by using coffee bags specifically manufactured for this purpose, those with a one-way gas valve. Now we realise, it is not. These one-way gas valve coffee bags are mostly made of multiple layers and as such do not harmlessly compost within a short time frame.
Several companies offer compostable and biodegradable bags, where a single component layer has passed the necessary standard (EN 13432) to prove that the packaging is both compostable and biodegradable. However, this does not mean that the overall bag is biodegradable. The finished bag often contains multiple-layers bound together by glue and contain a one way gas valve that bears little resemblance to the original EN 13432 compliant layer. The completed bag being far greater than the sum of it’s component parts. If it were indeed compostable it would bear the seedling logo as proof, (see below) we have yet to find a multi-layer coffee bag that legitimately displays this logo. Does one actually exist?
Before we answer that question let us look at the regulations in a little more detail.
The Seedling Logo
EN 13432.
This is the European standard which determines whether packaging is both compostable and biodegradable. If it is it can display the seedling logo, along with a unique certification code. A link to the British Plastic Federation site can be found here. http://www.bpf.co.uk/topics/standards_for_compostability.aspx
It does this using 5 key tests.
* Disintegration – packaging sample mixed with organic waste, in ‘ideal conditions ‘ 90% of it should break down into particles no bigger than 2mm within 12 weeks ‘.
*Biodegradability – measures the microbial conversion into water, carbon dioxide and new cell biomass within 6 months (must be 90% converted).
*There must be no negative effects to the composting process.
*Low levels of heavy metals.
*Composted packaging must have no negative effects on soil density, ph, salinity, or composition of total nitrogen, phosphorous, magnesium and potassium.
Once the packaging has successfully completed these tests and carries a compostable logo it can be placed in your green bin to be disposed of industrially to produce plant friendly compost.
There is one further complication, this directive only applies to Industrial composting as opposed to home composting.
Industrial composting, is controlled – It heats the packaging to 58 degrees and should disintegrate within 84 days. At least 90% carbon dioxide (compared to control material) within six months. If it passes these tests it can carry the seedling logo.
Home composting, is done by you and me by various means. At 20-30 degrees the packaging should disintegrate within 26 weeks. At least 90% carbon dioxide (compared to control material) within one year. It can then display the vincotte ok compost logo.
There are no current national or international standards for home composting.
I live in Northamptonshire and my local authority does not permit me to put my ‘compostable’ coffee bags into my green waste bin. If I did, my bin would be red tagged and the contents not disposed of until the item was removed.
With this in mind we thought we would compost our eco friendly coffee bags at home to see how long it took, for them to biodegrade. (A single layer of plastic had passed the EN 13432 tests, the bag did not display the seedling logo). Check out how it composted below.
Non Compostable Coffee Bags
The non compostable coffee bags were photographed once per week and their biodegradation followed. The first years worth of photographs can be found in the slideshow below. We have selected one photograph per month to show how little the single use plastic bags actually decomposed over the whole year.
Compostable Coffee Bag
According to the distributor, the individual components of the compostable coffee bag all conform to EN 13432. The bag itself does not carry the seedling logo as the finished bag has not, as far as I am aware, been submitted in its entirety for EN 13432 compliance. We decided to compost the bag ourselves to see how the overall bag faired. We took 1 photograph per week, the first years worth of photographs can be found in the slideshow below. We have selected twelve photographs or one per month to follow the compostable bags decomposition.
Refill Paper Bags
The refill paper bags were also composted. We only managed to take 7 photographs (one per week) before they disintegrated and became unrecognisable from all of the other compostable material. The 7 photographs are shown below. We will be unable to add any more updates on the paper bag, as to be honest we can no longer find it within the compost heap.
Conclusion
We have been composting both types of coffee bag for over one year now. It seems apparent that the compostability of both bags is questionable. Clearly the compostable bag is biodegrading at a faster rate than the non compostable bag, yet it still remains largely intact even after one year. The kraft paper covering on the bag has completely gone but the plastic layer remains largely intact and has not yet significantly decomposed. The one- way gas valve reappeared on week 37 and showed no signs of decomposition. It has once again disappeared into the compost heap, we will post a photograph of it if ever reappears.
By now in order to qualify for the seedling logo, 90% of the coffee bag should have fully disintegrated. It clearly has not. It seems unlikely that the multi-layered bag will ever qualify for the seedling logo which means both bags are polluting our planet.
We at Corby Coffee will cease to use single use plastic coffee bags which harm our planet with immediate effect. To find out what we are using instead please click on the link below. https://corbycoffeeroastingcompany.co.uk/plastic-free-how-it-works/
Potato Starch Bags
We came across these bags by accident when we found one lying in the street during lockdown. We instantly realised that they were potentially exactly what we had been looking for. After taking it home, we immediately put it into our home composting pile and began testing its compostable credentials immediately. The first 18 weeks of photographs are contained in the slideshow below.
It seems obvious to us that these potato starch bags are an ideal way to package ground coffee in a way that removes the single use plastic content. The leftover bag can then be added to your home composting pile, or else placed in your green bin for to be industrially turned into compost.
We are starting to use these bags immediately and can now offer ground coffee to our customers.