Removing unwanted macro, micro and nanoplastics from fresh produce production

Much of the European supply of vegetables and fruit is produced in Almeria, where standard practice is to cover the crops in plastic tunnels or plastic mulch which is then ploughed into the soil when the crop is harvested. The mulch is used to keep the soil temperature warm enough for plant growth, to prevent evaporative water loss, to suppress weed growth instead of using herbicide, and to reduce soil erosion. Nanoplastics (<1000nm) are expected to be generated by repeated cultivation of land containing waste plastic mulching material. Leafy salads also use plastics throughout the supply chain, in order to maintain freshness of the crop, to prevent microbial contamination, and to extend shelflife. Almeria produces the major proportion of conventionally and organically grown salads consumed in the UK between September and March. Disposable plastics are used throughout the supply chain for crate liners, wrapping pallets and product packaging. In the case of crate liners and pallet wrappers, waste management streams are well controlled, enabling most UK fresh produce businesses to claim zero waste to landfill. However, packaging used for bagged baby and cut salad leaves does not have a good waste management stream and companies are starting to explore alternatives including biodegradable and compostable packaging.

The project will evaluate the potential for bio-based packaging to preserve leafy salad quality and shelf life, alongside assessing the ability of these types of packaging to degrade in different environments that reflect possible disposal routes.
The project will evaluate the sustainability of different production and supply chain practices in relation to plastic use and ensure that alternative materials to hydrocarbon polymers represent a real improvement in sustainability.