Programmed emulsions for reduced levels of salt or sugar in liquid and semi-liquid foods

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

This project is concerned with salt or sugar reduction in emulsion based liquid and semi-liquid foods. The research hypothesis is that programming emulsions for oral release of a concentrated salt or sugar enriched encapsulated aqueous phase will enable reduction of the overall salt or sugar level in the food while maintaining consumer acceptability. The strategy is to encapsulate salt or sugar in starch stabilised water-in-oil-in-water emulsions (wow/s) and quantify their microstructure stability (relevant to product shelf life) and their tastant release properties (relevant to consumer satisfaction) adopting in-vitro and in-vivo methodology. Emulsion breakdown and thus tastant release during oral processing is mediated by the actions of salivary amylase and mechanical forces from teeth and tongue. Starch will be selected from native and ingredient starches which have not previously undergone modification to impart interfacial activity, and processed to impart or enhance ability to stabilise oil-water emulsion interfaces, including co-processing with emulsifying food ingredients, as well as from commercially available chemically modified starches with emulsifying properties. The internal water-oil interface will be stabilised with polyglycerol polyricinoleate (PGPR), fat crystals or food particles. Microstructure changes and saliva-starch interactions during the oral processing of the emulsions both with encapsulated salt and sugar will be and the findings will be correlated to sensory taste perception data. This will guide optimisation of the interfacial design of the emulsions and ultimately lead to a model for the emulsions' taste enhancing properties which will be validated on the basis of relevant foods and sensory analysis.

The research contributes to Research Challenge 1 & 2 "Understanding the relationship between food processing and nutrition" & "Designing foods to maintain and improve health".
Beneficiaries of this research will be the food industry, food ingredient industry, the government and the general public. The research will enable the food industry to develop a broader range of liquid and semi liquid foods such as sauces, salad dressing, soups and milk shakes with reduced salt and/ or sugar levels quite quickly. It will help the food industry develop more innovative products based on this approach, with novel taste profiles to perhaps enhance the perception of fat and other components to improve the sensory qualities of healthier foods which have been associated with poor sensory quality.
The proposed technology to achieve this goal will not compromise the taste of these foods as it is known to the consumer. Thus, these foods will help contribute towards reduced salt or sugar consumption based on processed foods. A decrease in the occurrence of associated health problems benefits the wider public and has wider consequences on the spending of the government. Current estimates state that up to 9,000 lives could be saved from CVD and high blood pressure and savings to the NHS will be around £1.5b if salt levels reduced to recommended levels. Consumers will also benefit from a greater choice of foods with reduced salt and sugar, and will no longer have to compromise taste in order to rapidly decrease salt or sugar intake.
The research is centred on a widely used food ingredient as technology enabler and this will benefit the food ingredient industry in terms of wider market potential and development opportunities for increased ingredient functionality.

There could also be broader benefits to the pharmaceutical, medical, cosmetic and agrochemical sectors, seeking new and effective ways of targeted delivery of bioactive ingredients.
This project will provide interdisciplinary training to two postdoctoral research associates who will gain experience in working with a widely used food system including processing and characterisation (emulsions) applying technology of increasing interest in industry (particle stabilisation) while gaining knowledge on the widely utilised food ingredient starch and exploring physical processes to improve their performance as emulsifiers. The research will also involve use of an extensive range of analytical techniques as well as working with human subjects (oral residence time analysis and sensory panel). This training will equip the researchers with a broad skill base who may then seek future employment in the food industry. The research will also have an impact in the scientific community as we will disseminate our findings through the traditional channels of peer reviewed papers and conference attendance.