NutriNano: Feasibility study on application of natural and liposomal bioactive ingredients for improved nutrition

Dietary intakes of omega-3 long chain polyunsaturated fatty acids (O3LC-PUFAs) play an important role in the regulation of the development of the brain and normal heart function and the regulation of blood triglyceride content including, inflammatory and immune responses. The European Food Standards Authority (EFSA) approval of health claims relating to the benefits of O3LC-PUFA intake concluded that 250mg/day is required for the maintenance of general cardiovascular health among healthy adults and children and 2-4g/day is needed for maintenance of blood pressure and triglyceride levels.

Presently, the main sources for O3LC-PUFAs are fish and fish oils, however, the production of these sources is unsustainable and unlikely to meet the growing demand, especially for vegan sources. Only 25% of the UK population are oily fish consumers and further decreases are anticipated due to growing plant-based diets and sustainability concerns. Microalgae such as _Chlorella vulgaris_ provide a sustainable alternative source of O3LC-PUFAs, however food products containing them have poor consumer acceptance due to strong 'fishy' odours. Furthermore, they lack efficacy with regard to dose of O3LC-PUFAs delivered (poor bioavailability) increasing the gap between dietary intake and recommendations (particularly for children, teenagers, females and pregnant women) which has significant implications for human health in current and future generations.

Liposomes (small oil droplets) exist in many foods naturally in the form of emulsions, such as human milk. Ultrasonic cavitation (UCav) of oils generates nano-sized droplets (nano-liposomes) which in the presence of water or aqueous solutions creates nano-emulsions. Oils in nano-emulsions survive passage through the digestive system (bioaccessibility), are more readily digested and absorbed from the gut (bioavailability). UCav is energy intensive and has limited scope for industrial scale nano-emulsion production. This project will evaluate more sustainable, scalable, mechanical cavitation (MCav) methods for microalgal oil nanoliposome production which, in association with flavour masking techniques, will aim to produce various readily-consumed foods and supplements containing O3LC-PUFAs with improved bioaccessibility and bioavailability. The performance of these innovative functional foods and supplements will be determined through _in vitro_ digestion (human digestive models), whilst consumer acceptance will be determined through use of sensory panels. Extended shelf-life of the nano-liposomes in nano-emulsions will be evaluated through the addition of polyphenols which act as anti-oxidants.

This project will help to pave the way towards the development of a wider range of functional foods. These have potential promise to help close the omega-3 dietary gaps and promote health in adults and children.