When an egg is cracked, the inside is consumed and the shell is considered waste and thrown away.
Canada produces about 615 million dozen eggs per year. About one quarter of those eggs go to the food industry, where they’re broken and used for processing into various products. That results in almost 45,000 tons of egg shells every year that need to be disposed of – and that disposal costs money, an estimated $1 – 2 million annually. And this does not include shells from 70.2 million hatching eggs.
What if, instead, those egg shells could be of value?
That’s what Alphonsus Utioh and his research team at Manitoba’s Food Development Centre in Portage La Prairie, and Burnbrae Farms Ltd., one of Canada’s largest egg producers, have set out to discover.
“Studies have shown that egg shells are a good source of dietary calcium with potential applications for the food, cosmetic and pharmaceutical industries,” says Utioh. “And there are other uses too, such as in animal feed supplements, and in fertilizer as a soil conditioner.”
The shell makes up about 11 per cent of the total weight of an average egg, weighs about six grams and contains approximately 2,200 milligrams of calcium, as well as other minerals such as potassium, magnesium, and iron, and extracts like collagen. The waste when an egg is broken includes both the shell and the membrane.
The key, says Utioh, is to develop a cost effective and simple way to process egg shell powder so it can be used as a functional food ingredient.
He’s been working with the Burnbrae egg processing facility in Winnipeg to process the egg shells by washing, sterilizing, drying, grinding and sifting to create an egg shell powder.
Initial analysis of the powder has shown that it’s safe and without bacterial contamination.
“Our preliminary results show potential for this process to produce egg shell powder as a source of dietary calcium at about 38 milligrams per gram of powder, and without any issues related to safety,” he says.
Through the course of the work, Utioh and his team discovered that it could be possible to recover the egg shell membrane through the shell powder process. The membrane contains about 10 per cent collagen, which could be extracted and used for food, cosmetic, and pharmaceutical applications.
Future work includes continuing to optimize the shell recovery process for hardboiled eggs, as well as developing and optimizing a process for raw egg shells. The processed egg shells will be ground to produce egg shell powder with suitable particle size for food applications.
“We expect to develop two food products using egg shell powder and then test them in terms of sensory attributes,” says Utioh. “The question will be whether the market will accept it.”
Why is this innovation important?
Health: The ground egg shell powder contains 37 to 39 milligrams of calcium per gram, making it a potentially excellent source of calcium in the human diet.
Economics: This innovation lets egg processors not only save money on shell disposal costs, but allows them to open new revenue streams through the added value of the shell powder.
Markets: Development of products incorporating egg shell powder could bring new market opportunities to egg processors, as well as others in the food, cosmetic and pharmaceutical industries.
What does this innovation mean to Canada’s food processing industry?
This innovation will allow egg processors to turn a costly waste product into a value-added revenue source that is also beneficial for health and nutrition.
About Burnbrae Farms Ltd.
Burnbrae Farms is a family owned and operated company that has been producing eggs for over 70 years. Burnbrae is one of Canada’s leading egg producers with farms in Ontario, Quebec, Manitoba and Alberta and British Columbia; and processing plants in Eastern and Western Canada. They sell eggs and egg products including hard-boiled eggs to major grocery store chains, food service operations and large
bakery and industrial customers throughout Canada. www.burnbraefarms.com
About the project team
Alphonsus Utioh is Manager of Research and Development at the Food Development Centre (FDC). He has conducted and managed many industry-driven food processing research and development projects, and has a Master’s degree in Chemical Engineering from the University of Saskatchewan. Alphonsus is a registered Professional Engineer with the Association of Professional Engineers and Geoscientists of Manitoba, and an Adjunct Professor in the Department of Human Nutritional Sciences, University of Manitoba.
Other project team members are Paulyn Appah, PhD, Senior Process Development Consultant with expertise in thermal processing and extrusion; Meeling Nivet, BSc, Group Leader, Product Development with expertise in liquid food processing; Janice Meseyton, BHEc, Senior Product Development Consultant with expertise in bakery and cereal products; Ramachandran Gopal, ME (Ag); and Carol Nabanoba Musoke, BEng, EIT.