OMEGA: fish Oil MicroEncapsulation Generating fortified food products for improved humAn health

The OMEGA project aims at preparing products that can help people increase their intake of healthy omega-3 rich fish oils and at the same time utilize rest raw materials from fish production in an optimal way. The project is a cooperation between SINTEF, NTNU and the Western Norway University of Applied Sciences, together with The Technical University of Denmark and Amity University, India. Polyunsaturated omega-3 fatty acids, so-called Omega-3 fish oils have a well-documented positive effect on human health. Still, a significant fraction of the population does not consume the 2-3 fish meals per week required to reap these health benefits. This might, in many cases, be caused by a dislike of fish flavours, or unwanted smell and taste of fish and fish products. By encapsulating omega-3 oils they can be protected against oxidation, and the microcapsules can be added directly to food products to ensure a regular intake without unwanted flavour, and without having to take omega-3 supplements. At the same time, we need to utilize rest raw materials including skin and backbones from domestic fish production in a more effective way. A challenge is to obtain good quality omega-3-oils and fish proteins like gelatin from rest raw materials. Another problem is that some consumers may have concerns about eating food derived from such materials. In the OMEGA project, we are working on improvement of the extraction of omega-3 oils and fish gelatin from salmon rest raw materials. The salmon oil extracted from fresh salmon skins and bones in the project has a very low amount of oxidation products like peroxides (PV<4 meq/kg oil) and aldehydes (AV<2). The sum of healthy omega -3 fatty acids in the oil (EPA and DHA) was obtained to be approx. 5% of total fatty acids. We found that the technological solution used for extraction of oil influences the extracted oil quality. A crystallisation process has been used to remove some saturated fatty acids from salmon oil to upconcentrate the unsaturated omega-3. Enzymatic modification of salmon oil is an alternative technology to increase omega-3 fatty acid amount in the oil and is on-going study. We are also looking into the use of oil soluble natural plant extracts as antioxidants. A mixture of tumaric, clove and black pepper extracts were most effective to reduce oxidation in salmon oil. Different pre-treatments were used for removing non-collagenous materials from salmon skins. Several extraction technologies were applied to identify the technology providing the best yield and amino acids composition for obtained gelatin. Both salmon skin and bones gelatin together with white fish heads gelatin (as market leading control) were provided for encapsulation tests. In addition, extraction yield and quality of extracted gelatin using several preservation methods (freezing, salting and preservation by low pH) were evaluated for salmon skins. Several stage fractionation and processing technology was proposed to ensure full utilisation of the whole rest raw material (skin). The pure omega-3 oils are microencapsulated to prevent degradation and mask off-flavours. So far, microcapsules containing fish oil with and without antioxidants have been prepared, and the shelf life of the capsules is under investigation. We have investigated the effect of using different microcapsule wall materials like gum Acacia in combination different salmon gelatins. A novel spray drying method wherein the salmon oil is simultaneously microencapsulated and coated with a secondary barrier layer has been developed, and provides better protection for the salmon oil, whilst simultaneously giving particles that are more compatible with food matrices. Microencapsulated powders with salmon oil and salmon skin gelatine were applied in different food systems to study their functionality, stability, and sensory properties in different matrixes. We have provided demonstrations of fortified food twice; a fortified smoothie, and fortified bread and soup. The demonstrations provided valuable feedback from the participants. We also investigated consumer concerns and perceptions towards foods fortified with ingredients (proteins and oils) from marine rest raw materials. A focus group study was conducted with > 40 participants being interviewed about their food choices, sustainability, fortified food, and thoughts about introducing food with underutilized fish parts in their diets. The results indicate their market potential; however, taste and texture can still be an issue. To further explore this, we conducted a sensory evaluation of strawberry smoothies fortified with various quantities of microencapsulated salmon oil powder. 102 consumers tasted and evaluated the smoothies by indicating their overall liking, purchase intentions and selecting the sensory properties that they believe best describe the smoothies. The consumers’ general health interest, food neophobia and environmental concerns were also evaluated.

Despite the well-documented effects of polyunsaturated omega-3 fatty acids in fish oils on human health, a significant fraction of the population does not consume the 2-3 fish meals per week required to reap these health benefits, at least in part due to unwanted smell and taste of fish and fish products. In OMEGA, we seek to overcome these challenges by (i) improving extraction of omega-3 oils and fish gelatin from salmon rest raw materials (RRM), (ii) microencapsulating fish oils to avoid degradation and mask off-flavours, (iii) incorporating the microencapsulated fish oil into food products, and (iv) evaluating the resulting sensory properties and consumer acceptance. The OMEGA project will move beyond the state of the art and will address key aspects in order to improve encapsulation of fish oils with salmon gelatin to facilitate increased local use of domestic raw materials. Additionally, OMEGA will investigate and seek to address consumer concerns and perceptions towards RRM based materials. Critical R&D challenges to be addressed in OMEGA include producing sufficient quality oils and gelatine from farmed salmon RRM, and developing fish oil microcapsules which are sufficiently stable to protect the oil from oxidation during incorporation in accessible food products. The project will also address consumer perceptions of RRM fish oils and fish gelatins, and whether micro-encapsulation will ameliorate concerns regarding perceived off flavours / materials traditionally associated with fish and fish products. The OMEGA project will move significantly beyond the state of the art, and will address key aspects of the associated challenges, working to improve encapsulation of fish oils from RRM with fish gelatine and their incorporation into accessible food stuffs. The knowledge gained in OMEGA will have translational value towards fortification of food with different oils and marine RRM.