Industrial eggshells are considered a hazardous waste in the EU and producers must pay to dispose of them correctly, which can be costly. A medium-sized egg processing facility in the EU can expect to pay up to €100,000 a year to transport and dispose of its shell waste, according to one estimate. If eggshells are disposed of in a landfill site without being treated first, they can attract rats and other pests.
However, eggshells are a source of valuable nutrients that, with the right investment, can be upcycled and used in added-value products. Eggshell membrane – the thin film that can be seen when peeling a boiled egg – is primarily composed of collagen type I but also contains chondroitin sulphate, glucosamine, and hyaluronic acid, as well as other nutrients.
Scientists at Norwegian research institute Nofima have been working to develop methods to upcycle this “very promising” biomaterial that can be easily installed in a factory setting. Given that, in the EU alone, around 150,000 tons of eggshell waste is generated each year, there is a significant and largely untapped potential source of supplies.
“We have worked with eggshell membrane as [a] bioactive material since 2013, first with a focus on wound-healing potential, followed up with research showing this as an excellent biomaterial for tissue engineering, and now research with positive effects on skeletal muscle during oral intake as a nutraceutical,” said Mona E Pedersen, senior scientist at Nofima.
“This material is known for its health benefits in relation to bone health and pain relief, but the novel work performed by Nofima, in collaboration with industry, is the source of the eggshell membrane used in the research. The eggshell membrane is processed at an industrial egg factory, which makes it much more accessible as an industrially available material,” Pedersen told Vitafoods Insights.
Nofima has been working with Norilia, a wholly owned subsidiary of Nortura, one of Norway's biggest food manufacturers that produces both meat and eggs and is a farmer-owned co-operative.
Thanks to the partnership, Norilia has developed an on-site method to separate the membrane from the shell in what it describes as a unique and novel way that is more effective, hygienic, and cheaper than existing methods. After separating the membrane, it dries and grinds it to a powder.
Improvements in muscle structure and grip strength
Pedersen and fellow Nofima scientist Sissel B Rønning tested the effect of this eggshell membrane powder on muscles and inflammation. Through in vitro, in vivo, and mouse studies (not peer-reviewed), they found that consumption of the powder can reduce the muscle loss that is universally experienced after the age of 40.
In one mouse study, the scientists fed middle-aged mice eggshell membrane powder as part of their diet until the mice reached old age. When the scientists studied the mice’s muscle structure, they found that it resembled that of younger mice, and that grip strength was improved.
“The membrane prevents you from dropping things as much. Grip strength is a physiological function – we hardly expected to see any effects on that,” said Pedersen.
The researchers then conducted a small human experiment in which elderly, healthy participants took eggshell membrane supplements for a short period of time.
As extracting muscle samples is highly invasive, Pedersen and Rønning instead took blood samples from the participants and observed an anti-inflammatory effect. Mild inflammation is one of the factors that contributes to age-related sarcopenia, they noted.
On the market: Chronic wound dressing
Norilia is already supplying the Norwegian medical startup Biovotec with eggshell membrane powder to make a wound contact dressing. The use of purified eggshell membrane protein in the dressing optimises the microenvironment for chronic wound healing.
“This previously expensive waste product has now become a valuable resource for solving a serious health problem,” said Norilia.
Based on the findings of the most recent research conducted by Pedersen and Rønning, Norilia said it may explore other applications in the nutraceutical sector.
“We see several interesting applications for the membrane in high-value products – for example, in dietary supplements,” said Heidi Alvestrand, director of business development at the Oslo-headquartered manufacturer.
“This project is very important to us in order to test the membrane, investigating what functional and bioactive properties it has and how it can be used. It is especially important for us to document the health-related properties and their effects,” she added.
Upcycling calcium and other nutrients from eggshell waste
Another company operating in this space is Dutch startup DEPP. It has developed an eggshell membrane protein powder called Eggbrane that can be used in food, supplements, pet food, cosmetics, and pharmaceutical applications.
DEPP separates the membrane using a mechanical method based on water and pressure. The fact that no chemicals or heat are involved preserves the properties of the membrane, it said. The ingredient improves joint flexibility and regenerates tissue while relieving pain and reducing inflammation, making it beneficial for conditions such as osteoarthritis, said DEPP.
US company EggTech, owned by parent company Toman Industries, has developed a method to extract calcium from eggshells. It said its calcium offers greater bioavailability and is more easily absorbed than traditional mined calcium.