Sustainable biotechnological solutions for RRM and wash water processing

This report is a part of results generated within ReValue project and defined as Deliverable 2.2. Report on sustainable biotechnological solutions for RRM and wash water processing. Report covers technologies, which could be applied for utilisation of rest raw materials and wash water obtained from surimi processing industries. Results indicates that processing of Pink Perch and Croaker RRM (head & viscera and skin & bones) which contains valuable nutritional compounds can be used for production of nutritional protein hydrolysates with desirable functional properties as well as for extraction of marine gelatine. It was concluded that all tested enzymes yielded good quality protein hydrolysate and the highest yield as well as protein quality was obtained using Alcalase. It is shown that increased enzyme concentration (up till 2% amount of dry material) can be used for production of hydrolyses from dried RRM. The potential of application of lactic acid for the protein precipitation from wash water was indicated. Treatment of wash water with acid led to removal of 87% of protein from wash water. Several extraction technologies were applied on RRM to extract gelatine indicating the potential of RRM to be used as sources for marine gelatine. However, it was concluded that initial drying of raw material or use of too concentrated acid for pre-treatment could be the reason to have low gelatine yields.