Can I Compost My Food Caddy Bags/Liners?

Friday, 14 October 2016  |  HOTBIN Composting

Compostable Food Caddy Bags/Liners and the HOTBIN

Can I Compost My Food Caddy Bags/Liners?

Made from corn starch, plant extracts and even paper, the majority of food caddy bags in circulation today are both biodegradable and compostable.  These bags do biodegrade in the HOTBIN under certain circumstances and actually very quickly; in our tests at 60°C they broke down within 30 days.

Caddy with Compostable BagShould I add these to the HOTBIN?

Although biodegradable/compostable caddy bags will break down in the HOTBIN we do not advise adding them because they would need to be shredded first; not a practical solution when bags are full of food. If added whole, the caddy material would form layers in the HOTBIN restricting airflow.

But it’s convenient to throw the whole bag and contents in!

It is convenient, but not the best idea. We’ve had some feedback from customers who have been using caddy liners; the first is a cafe customer who has been collecting food waste from the kitchen in compostable bags and loading these straight into the HOTBIN and the second a Yurt Holiday Camp Site adding bagged humanure from their dry toilets into HOTBIN. Both of these customers have experienced problems in doing so!

We appreciate the convenience that these caddy liners offer however it is crucial to the HOTBIN’s operation that bacteria have an easily accessible food source. Adding waste in these bags makes this food source harder to access as it creates a protective layer which bacteria will need to breakdown first before being able to access the waste inside - ultimately prolonging the decomposition process.

In detail, the bag effectively “seals” the contents from airflow. The food inside the bag decomposes anaerobically during the first 1-10 days before the bag itself degrades. This leaves a mushy smelly mess, the bags then compress and form an impervious layer causing the bin to cool and turn anaerobic. As the temperatures fall, the bag decomposition slows leaving you with a HOTBIN that needs completely emptying and all the bags separating out – a very unpleasant job.

Why Doesn’t the Council Have Problems?

Caddy bags offer residents a convenient way to bag up their waste and place it in the outside collection bin. The council however compost on an industrial scale where all waste is shredded before being processed through the composting plant. For this reason it doesn’t matter if waste is bagged up in caddy bags.

Recommendations?

If you are using these bags to line your kitchen food caddy, rather than adding them into the HOTBIN we would recommend emptying the waste from the bag into the HOTBIN first and disposing of the bag separately in your council waste collection.