Innovative products and technology-driven utilisation of rest raw materials (INTEREST)

The InteRest project focuses on using rest raw materials from food and seafood industries in processes for new value-added products. The aim is to exploit these materials as nutrients for selected fungi and bacteria for cost-efficient and sustainable production of 1) high-quality poly-unsaturated fatty acids (PUFA) from fungi, and 2) probiotic marine lactic acid bacteria in early-/start-feed of marine fish. The aim was also to carry out a socio-economic survey of the potential for rest raw materials from green and blue sectors. The project has had 5 work-packages (WP). WP1: Fish peptones were made from fish by-products using protein-cleaving enzymes. These peptones were used for cultivating fungi and carnobacteria (WP2). Chicken residues were also used to produce peptones using enzyme treatment with Alcalase or Flavorzyme. Alcalase gave the best yield. Preparations made on a larger scale were also investigated for suitability for cultivation of fungi.Good growth was obtained, but PUFA levels were low in these experiments. WP2: Potato, fish and chicken rest raw materials were treated in several ways and screened for their potential use as media components for growth of Mucor circinelloides and PUFA production. Potato residues and chicken intestines were the most promising materials. Processing included "steam explosion" (SE) and enzymatic hydrolysis. SE proved to be an effective way of homogenization and to increase solubility. However, potato starch has to be hydrolyzed to efficiently produce larger amounts of glucose required for PUFA production. Combination of materials were done to make microbiological growth media. The media gave growth and PUFA production at a similar level as commercial media. However, concentrations of PUFA, especially gamma linoleic acid, were unlikely to be sufficient for economically profitable microbial PUFA production and further optimization is necessary. The carbon/nitrogen (C/N) ratio in the medium is the key. C/N ratio was varied in these experiments, but further work on this is required to increase the amount of PUFA produced. This work has been published. In collaboration with a related project (SingleCellOil, p.nr. 234258), screening and measurement methods for PUFA in fungi were developed, especially using FTIR spectroscopy. Several papers has been published on this theme. Two strains of Carnobacterium divergens with potentially probiotic properties have been investigated with regard to growth on fish peptones. The amount of fish peptone and other media components were systematically varied to optimize growth. It was possible to increase growth rate and total biomass compared to a commercial medium. Carnobacteria were investigated for antimicrobial activity in vitro. We could not verify previously published antimicrobial activity. Later in the project, carnobacteria were grown on a slightly larger scale for use in feeding trials with cod larvae (WP4). WP3: Two fungal strains (Mucor sp.) were selected for DNA sequencing. It has been very challenging to get enough DNA with good enough quality for sequencing. A preliminary sequence of the M. circinelloides strain used in the project (VI04473) is available but is very fragmented. A better sequence (with PacBio technology) is required. In the final phase of the project, DNA of good enough quality could be prepared from biomass with low and high PUFA content. Samples were sent to Zymo Research for further epigenetic analysis. These results can also provide sequence information so that the genomic sequence can be improved. The results are not finished by the end of the project, but will be further processed with publication as a goal. WP4: A first feeding trial with carnobacteria as probiotics for cod larvae showed no effect. The experiment was repeated, with some modifications. Older cod larvae were used as the hypothesis was that the immune system must be developed before one can expect an effect of probiotics. In this later experiment, there were clear effects of probiotic feeding on both growth parameters (faster growth) and mortality (less for treated larvae). Microbiome analyses showed that the effects are not caused or accompanied by major changes in the microbiome composition. The results were presented at relevant conferences and a manuscript is in preparation. WP5: Investigations of the socioeconomic aspects and the value potential of residual raw materials in Norway have been carried out. Two reports describing these results has been prepared. The first of these reports, dealing with residues from agriculture, has been published (Nofima report) and the second report (Nofima) focusing on marine residues, can be expected just after the end of the project. A workshop, "Food2Food seminar", with both Norwegian and international stakeholders and participants, partly in collaboration with Innovation Norway, was organized in 2016 at Nofima, Ås, to illustrate these aspects.

The InteRest project focuses on using rest raw materials from food and seafood industries in processes that result in new value-added food and neutraceutical products as well as ingredients for improved health in seafood biomass production. In this way, t he rest material is also considered as a product. The project represents a multidisciplinary and intersectorial approach for use of processed rest material biomasses as sources for new biotechnology-guided production processes of valuable products. The p roject aims to exploit these materials as nutritional additives to selected fungal and bacterial cultures for cost-efficient and sustainable production of 1) highly demanded high-quality poly-unsaturated fatty acids food components or neutraceuticals from fungi, and 2) requested probiotic marine lactic acid bacteria in early-/start-feed of marine fish. For additives providing enhanced synthesis, the underlying molecular mechanisms and related pathways will be revealed using state of the art technology app roaches such as genomics, transcriptomics, epigenetics and bioinformatics. Lessons from these analyses will provide important knowledge on which rest materials and processing steps are most efficient for each stage of the pathway. The aim is to produce pa rticular fractions of rest materials that separate or combined give optimal stimulation of fungal PUFA production for high-end food supplement and of probiotic carnobacteria for increased survival of juvenile cod in aquaculture. For the benefit of bioecon omy-based green and blue biotech and food industries, we also propose a socio-economic survey of agri- and aquaculture sources for food production, their rest materials and exploratory potential. We perceive the proposed InteRest activities and goals to be innovative and interdisciplinary representing intersectorial industry interests.