How eggshell recycling could save waste and create new materials

by Ray Cooling

It must be the ultimate in recycling … using previously unwanted eggshells to protect eggs!

The project devised by scientists working in the United Kingdom plans to turn eggshells into plastics that could be used to manufacture anything from food packaging to construction materials.

Part of project will see matter extracted from eggshells that may prove valuable in the pharmaceuticals industry. A research project at the University of Leicester, central England is looking at eggs and eggshells in a fresh light and is being funded by the UK’s Food and Drink iNet (innovation network).

The plan is to find useful ways of recycling eggshells that are currently regarded as waste by food producers and which has to be disposed of in landfill sites at serious cost.

The Food and Drink iNet is supporting the project with the university to discover innovative ideas of using eggshells practically in various ways to be seen as income generating by egg producers, rather than a financial drain on their business. Scientists in the Department of Chemistry at Leicester University who specialise in ‘green chemistry’ and sustainable materials are looking at how to extract glycosaminoglycans (GAGs), proteins that are found in eggshells. GAGs are used in numerous biomedical applications and could prove useful in pharmaceuticals.

The Just Egg company in Leicester is a hard-boiled egg and mayonnaise manufacturer that uses about 1.3 million eggs every week, creating 10 tonnes of eggshells. The firm spends about 30,000 pounds a year sending 480 tonnes of shells to landfill for disposal. Managing director Pankaj Pancholi believes the research could bring big benefits to the food and drink sector. “If I wasn’t spending the 30,000 pounds a year on landfill costs I could employ another worker or two part-time workers, or invest that money in research and development and innovation,” he said.

“It would be great if the eggshells could ultimately be recycled to be used in the plastic packaging that we use for egg products, like our new hard-boiled eggs in packs. This is a really exciting project,” he added.

Part-funded by the European Regional Development Fund, the Food and Drink iNet has awarded almost 20,000 pounds towards the project that will include the sharing of the results with food manufacturers across the English Midlands and beyond. The iNet was established in 2008 to coordinate specialist support to stimulate innovation in the industry.

Professor Andy Abbott, from Leicester University, said: “We specialise in researching and developing innovative manufacturing solutions around recycling technology. This project is focused on researching novel methodologies for recovering and reusing a waste stream into a sustainable, financially viable material supply locally. The R&D funding from the Food and Drink iNet is very timely and very gratefully received.”

The iNet-funded project aims to develop and validate the pre-treatment process of the eggshell needed to make it sterile, develop a method for the extraction of GAGs from eggshell and analyse the products obtained.

It will develop a post-treatment process to convert the eggshell into a starch-based plastic, test the mechanical properties, including the strength of the new material and make various materials to optimise the eggshell loading and particle size. The Food and Drink iNet- based at Southglade Food Park, Nottingham, with a team of advisers across the East Midlands – is managed by a consortium, led by the Food and Drink Forum and including Nottingham Trent University, the University of Lincoln, and the University of Nottingham.

It coordinates specialist support to stimulate innovation in the food and drink sector to increase competitiveness, sustainability and growth. The iNet is also a key partner for businesses, universities and individuals working and collaborating in the industry in the East Midlands and nationally.

The research is hoping to identify ways to use the eggshells as fillers that could be used to ‘bulk up’ different grades of plastic, with many sorts of applications from ready-meal food trays to shop fittings. The ultimate goal is to use the eggshells in packaging to protect egg products – giving a second lease of life to the eggshell in the very role it was created for – a true case of recycling.

“Eggshell is classified as a waste material by the food industry but is, in fact, a highly sophisticated composite,” said Food and Drink iNet director Richard Worrall. “The scientists at Leicester University have identified a number of uses for eggshell waste and the Food and Drink iNet is very pleased to support a ‘collaborate to innovate’ research project to examine eggshell recycling solutions. This could have potential benefit on many levels, both for food manufacturers and a much wider industry.

The research team led by Professor Andy Abbott, professor of physical chemistry and head of the Chemistry Department at Leicester University, is working in conjunction with Philip Chatfield, director of project management company Integrated Food Projects at Ashby de la Zouch. The project plans to involve a number of small and medium-size companies working in the egg business in the East Midlands region.

Share this: