From eggshells to new ingredients and biomaterials

- Eggshells contain both calcium and a thin, protein-containing membrane. Through collaboration and technology development, Norilia and its partners are making it possible to use these raw materials in new products.

Photo: Sune Eriksen

Thousands of eggs are cracked every day at Nortura’s facility in Revetal to produce egg ingredients and products. This generates large quantities of eggshells, which previously incurred disposal costs. A collaboration between Norilia, Nortura Revetal and biotechnology company Biovotec led to the establishment of an industrial production line that separates the membrane from the shell. The technology uses air currents in a cyclone, allowing the two components to be recovered separately.

Two raw materials with different properties

Eggshells consist mainly of calcium carbonate. The inside of the shell is lined with a thin membrane made up of a network of proteins, including collagen. Separating the shell from the membrane yields two raw materials with different properties and applications. Eggshell calcium is used in food supplements and soil improvers, among other applications. Eggshell membrane is used as an ingredient in food supplements, and research is also exploring its use in the development of biomaterials. Each application has its own requirements for composition, processing and documentation.

800 tonnes of eggshell at Nortura Revetal

Eggshell isn't just shell - the valuable membrane within the eggshell is separated from the rest of the shell using a unique process.

Eggshell membrane in medical product development

Biovotec has developed DermaRep®, a wound dressing containing processed and purified protein from eggshell membrane. The development programme includes preclinical and clinical investigations of the safety and performance of the finished product. This is a separate medical product, subject to different requirements for manufacturing, documentation and marketing from those that apply to ingredients for food and food supplements. Findings from studies of the wound dressing therefore cannot be directly extrapolated to eggshell membrane used as a food supplement ingredient. The collaboration demonstrates how a raw material from food production can provide a starting point for product development across disciplines and industries.

New opportunities for eggshells

Industrial separation of the shell and membrane makes both raw materials available for further processing and product development. Norilia is exploring new applications for eggshell calcium and eggshell membrane in areas including food, food supplements, animal feed and materials. This work involves assessing the properties of the raw materials, their performance in relevant products and the requirements for each application. The aim is to use more of the egg and develop new products from raw materials already available in food production.