# A Multidisciplinary Approach for Improving Resource Efficiency in the Indian Surimi Supply Chain
## 3 Synthesis of Key ReValue Results
### Valorisation Options for Upscaling  
A lack of proper utilisation of RRM is another shortcoming of the surimi industry. If fish intended for surimi production is filleted under good sanitary conditions, it results in fresh and human food grade quality RRM, which can be used for the production of valuable marine oil and protein ingredients. In order to obtain a more sustainable utilisation of this RRM, a techno-economically feasible process leading to high-quality products is needed. Sustainability means utilising the RRM, which can be applied for value-added products like ingredients for nutraceuticals or food as well as for livestock feeds, biogas, and fertilisers (Figure 5). ReValue project uncovered improved opportunities to address the RRM and improve the quality of fish. One of these ways includes transferring the process of removing and handling of RRM (i.e., de-heading) to the fishing vessels themselves to ensure an efficient quality control process [33]. This shift would decrease the chances of having spoiled fish ultimately equating to lost revenue. Spoiled fish can lead to a recall of an entire production batch which in turn would trigger elevated market expenses for the industry. To decrease the chance of this happening, employing traceability and temperature monitoring systems along the supply chain are important [31]. Traceability can increase the quality of surimi ventures through investments in information technology for restructuring the Indian surimi supply chain to global standards. Figure 3: A schematic diagram of a vapour absorption system for a fishing boat. Figure adapted from [35]. RRM from the surimi industry in India is currently used for feed/fertil applications or are discarded without any attempt to recover valuable components. To increase the value-addition along the supply chain by producing functional ingredients, high-quality fish and RRM are required. The ReValue project found that different RRM obtained from surimi processing plants in India have the potential to be used as valuable ingredients  
Figure 4: Schematic diagrams for baseline ammonia system (**left**) and a cascade refrigeration system (**right**), adapted from [37]. Figure 5: Possible value-added products obtained during surimi processing. in different formulations both for food and feed markets. Some variation in chemical composition, as well as microbial quality, indicated that proper storage and handling methods and optimal processing technologies need to be applied to produce high-quality final products. There is no regulation available for a microbiological load of fish-related raw material used in the food industry. According to FSSAI (Food Safety and Standards Authority of India) permitted aerobic plate count in fish mince/surimi and analogues are \(1\times 10^{6}\), but yeast and mould should be absent. Yeast and mould count for dried fishery product can be 500 CFU/g. Samples were analysed for aerobic plate count, presence of _E. coli_, _Salmonella_, Yeast and mould, and _Lactobacillus_ bacteria. No pathogenic bacteria were found in any analysed RRM, whole fish and surimi, wash water. Pink Perch and Croaker are the two main species used for surimi production in India. Screening for optimal processing technology along with optimisation steps indicated that Pink Perch and Croaker RRM (head & viscera and skin & bones) which contain valuable nutritional compounds can be used for the production of nutritional protein hydrolyses with desirable functional properties as well as for the extraction of marine gelatine. All tested enzymes including alcalase, a mixture of bromelain and papain, trypsin, and endogenous enzymes yielded good quality protein hydrolysate, and the most optimal enzyme gave the highest yield as well as protein quality was determined. The conditions for enzymatic hydrolysis of Pink Perch head and viscera employing Alcalase were optimised. The potential of the application of acids for protein precipitation from the wash water was indicated.