Background The tanning industry treats animal skins to produce durable leather products. It generates large volumes of by-products and waste materials, which can cause significant negative environmental impacts. The advancement of European policy and legislation protecting the environment has encouraged the exploration of ways to transform tannery waste materials into valuable products. Collagen and gelatine are important components of solid tannery wastes. The gel-forming properties of gelatine are the basis for classical applications in the food, photographic, cosmetic and pharmaceutical industries. However, potential new applications have also arisen, including for use as a micro-encapsulating agent. Micro-encapsulation involves covering tiny particles or droplets with a coating to provide useful new properties. It is showing potential for highly innovative technologies such as scratch-n-sniff, time-release pharmaceuticals and self-healing materials. INESCOP works on satisfying industry needs regarding applied research on the development and implantation of new materials and technologies, including micro-encapsulation. Laboratory trials made by INESCOP have demonstrated that an optimisation of the extracting conditions of collagen and gelatine from tanning waste is necessary to obtain the specific properties suitable to their use as shell-forming biopolymer of microcapsules. Objectives The main objective of the LIFE MICROTAN project is to demonstrate, on a semi-industrial scale, the technical, environmental and financial feasibility of the isolation of protein products - collagen and gelatine - with specific properties from tannery solid wastes. It hopes thus to enable their valorisation as natural micro-encapsulating agents in the production of active materials with functional properties. The project aims to design, construct and operate a demonstration plant for the treatment of solid tannery wastes from SMEs located in the countries participating in the project. It will develop a procedure for the optimum recovery of collagen and gelatine with the required properties for use in micro-encapsulation. It hopes to recover as much untanned waste as possible, with the non-collagenic fraction sent for composting. LIFE MICROTAN aims to demonstrate the production of microcapsules from the collagen and gelatine obtained in the demonstration plant and thus show the feasibility of the valorisation of this industrial by-product. It will conduct environmental and economic assessments of the potential of new products made from these former waste materials. Expected results: The project expects to achieve the following results: Identification of the best conditions for extracting collagen and gelatine from solid tannery wastes; Construction of a demonstration plant able to treat at least 50 kg/day of tanneries waste; Obtention of collagen and gelatine with the specific properties for use as shell-forming biopolymer or microcapsules; Valorisation of 15% of untanned solid waste generated by tanneries; Economic benefits from reduced waste transportation and valorisation of the collagen and gelatine by-products in new niche markets; and Environmental benefits from a reduced volume of waste from tanneries and a 10% reduction in waste transportation.