The current nut and fruit processing has a low raw material efficiency. Many of the resulting by-products, such as walnut shells, can be used for higher-quality applications. The work package aims to develop a manufacturing process for ground walnut or apricot core shells, which will be used in the cosmetics industry as exfoliating particles to replace abrasive synthetic particles (“microplastics”). Given the increasing accumulation of microplastics in ecosystems, food chains and likely also in the human organism, its replacement is a central challenge for the cosmetics industry. The development of natural, biodegradable alternatives such as walnut or apricot core shells can thus contribute directly to reducing the environmental impact in Germany and beyond. Natural raw materials sustainably extracted from walnut forests and/or AF systems offer significant marketing and differentiation potential due to the growing consumer interest in ecological products. Since ground walnut shells are rather pointed and therefore need to be supplemented by other ground shells, the project aims to improve the grinding process for the desired products so that the ground shells can be used as exfoliating particles without restrictions. In addition, ingredients used for biocosmetics should not be treated with gamma radiation, which is currently the usual antimicrobial treatment method of commercially available walnut or apricot core shells. The aim of the project is therefore also to develop an alternative treatment method for walnut or apricot core shells, which ensures the required microbiological quality while respecting the biocosmetic requirements.
