Article is available in full to IFST members and subscribers.

Register on the FST Journal website for free

Click the button to register to FST Journal online for free and gain access to the latest news


If you are an IFST member, please login through the Members Area of the IFST website. 













Circular economy

Circular economy

AMT Fruit, part of the Munoz Group, reduced its overall operational waste – the majority of which (81%) is citrus fruit waste – by 30% from 2015 to 2018[3]. The company works with over 250 growers to supply Tesco with 11 million boxes of citrus each year – approximately 140 million nets of citrus.

This waste reduction has been achieved in a number of ways including: revising and broadening product specifications, expanding sourcing countries, introducing new product lines and developing partnerships with food charities, which have received one million portions of fruit.

AMT conducted consumer research to gauge attitudes and as a result was able to work with Tesco to accept an increased amount of ‘scruffy’ fruit and to introduce a new giant line of over-sized fruit. This resulted in Spanish growers supplying an extra 10% of their crop to Tesco. Further improvements to the delivery strategies have extended the shelf life of citrus fruits by 40 million days.

However, despite this increased use of irregular fruit, the company still had in excess of 2,000 tonnes of waste each year from the UK operation. Citrus waste is wet and acidic and full of rots and moulds, making it unpalatable for animal feed, so all the remaining waste was being sent to AD plants.

At the start of 2018, AMT began a collaboration with AgriGrub, a company that feeds waste vegetables and fruit to the larvae of black soldier flies. When the larvae are an optimum size they are sold – branded as Calci worms – to pet food distributors and retailers as a form of live feed for reptiles.

Their virtuous by-product, frass, is a sustainable source of nutrients for plants and a novel bio-repellent for crop protection.

There is already a significant body of evidence on the efficacy of chitosan (the active component in frass) as a biopesticide. However for many years the cost of extracting the chitosan was considered too great, as the process involved boiling crustacean shells in sulphuric acid. Frass from insects, however, needs little processing and represents an economically viable source of chitosan for agriculture.

The company is focusing on higher margin crops which have few treatment options for pests and diseases as this is likely to give the best return in the least time. However longer term it hopes to find wider application of frass, especially where neonicotinoids are being phased out.

The first frass trials, on brassicas, showed a 94% reduction in aphid numbers on frass treated plants versus controls.



New FS and T website!

We encourage you to visit the new home for our Food Science and Technology quarterly magazine. This now sits as part of Wiley's Online Library. There, you can access all our past issues from 2017 up to our current issue. Access the new website here: 

View the latest digital issue of FS&T or browse the archive


Click here

Become a member of the Institute of Food Science and Technology