Fluid Gel-Based Confectionery Fillings

Confectionery products have been traditionally formulated largely empirically, and scientific understanding in the area tends to be acquired retrospectively. It is then not surprising that, outside chocolate, the study of confectionary formulations, and in particular confectionary fillings, have not received significant attention in scientific literature. The current project aims to investigate novel water-based or fat-rich and/or fat-continuous bakery filling microstructures and their associate properties.
Pladis is the second largest biscuit manufacturer in the world, and home to some of the world's best tasting and most loved snacking brands. The UK is pladis' largest manufacturing hub with 4,500 strong workforce and seven sites across the country, including the largest biscuit factory in Europe located in Harlesden, London. Our diverse portfolio of snacks includes popular household brands, such as, McVitie's, Jaffa Cakes, Jacob's, Mini Cheddars, Carr's, Flipz and Go Ahead (more information at pladis' website).
The proposed project aims to investigate the use of fluid gels to create novel bakery filling microstructures and properties. Fluid (or sheared) gels are a special class of soft matter constructs which have been explored for applications in foods and cosmetics. Fluid gels are suspensions of closely-packed microgel particles in a non-gelled continuous (typically aqueous) medium, formed via a nucleation and growth mechanism when a biopolymer/hydrocolloid solution undergoes gelation under shear (e.g. within a pin-stirrer device). The resulting high fraction of suspended hydrogel particles bestows fluid gels their unique highly viscoelastic (shear-thinning) behaviour. The particulate nature of the fluid gels (as well as the prevalence of inter-particle interactions) can provide a level of 'self- structuring' post formation. Fluid gels have also been used to produce foam microstructures, and there is potential for their utilisation as the continuous phases in oil-in-water emulsions. Such oil-in-fluid gel emulsions could lead to the development of baked fillings of enhanced mouthfeel, while the dispersed oil droplets can enable the loading of the fluid gel formulations with hydrophobic species (e.g. flavours).

The beneficiaries of the research and training of the CDT will be UK industry, the graduates of the programme, the wider academic community, and consumers :

(i) UK industry: the formulation sector is wide and diverse, and our industry partners are world-leading in a number of areas; foods (PepsiCo, Mondelez, Unilever), HPC (P+G, Unilever), fine chemicals (Johnson Matthey, Innospec), pharma (AstraZeneca, Pfizer, Imerys) and aerospace (Rolls-Royce). All projects are cocreated with industry, and cofunded - the majority will be EngD students based in company sites. Industry will benefit in a number of ways: (i) from a supply of trained graduates in this critical area, with > 90% of graduates of the programme to date getting jobs in formulation companies, and (ii) through participation in industry-academia research projects in which students work within the company on projects of practical value, (iii) through the synergy possible between companies in different non-competitive sectors (we have current projects between Mondelez and P+G, and Johnson Matthey and Unilever resulting from CDT linkages). We will also work with Catapult Centres, including the National Formulation Centre at CPI and the MTC at Coventry, to enhance the industry relevance of the CDT and train students in modern manufacturing methods.

(ii) Graduates of the programme: students are trained in a critical area where graduates are in short supply, obtain training and experience of the issues involved in industrial and collaborative research, present their work at external and internal meetings and get good jobs (>90% within formulation companies). Many of our graduates are now reaching senior positions in industry, and one, Dr Stewart Welch of Rolls Royce, is now the representative of Rolls-Royce on our Industrial Management Committee. In the next 5 years we will build at least 50 new projects with companies, creating EngD and PhD graduates, a new generation of leaders for the formulation industries.

(iii) Wider academic community in the UK and elsewhere. We will ensure that students on the programme write papers (as many as possible with industrial co-authors) on formulation projects. This is a vital part of the CDT, as it both ensures and demonstrates the academic quality of the programme. We have published extensively in areas such as; soft solid mixing processes (Unilever, Johnson Matthey; see Hall et al., Chem.Eng. Res. Des. 91, 2156-2168, 2013); food materials for enhanced mouthfeel, low-salt and low-sugar delivery, (Pepsico, Nestle, Mondelez; such as Moakes et al RSC Advances 5, 60786-60795, 2015); design of innovative cleaning strategies (Unilever, GSK, Heineken, P+G; Food Bioprod. Proc., 93, 269-282, 2015); characterisation of domestic cleaning processes (washing machines and dishwashers) to minimise water usage (P+G; Chem.Eng Sci., 75, 14, 2012); in-vitro models for formulated product breakdown and nutrient and drug delivery in the mouth, stomach and GI tract; EngD work followed up by BBSRC and industry funding (Eur J Nutr. 55, 2377-2388, 2016); dynamics of spray driers (P+G, AIChE J 61 1804-1821 2015; Chem. Eng. Sci. 162, 284-299, 2017), and ways to reduce waste in soyamilk production (Unilever; Innovative Food Science & Emerging Technologies, 41, 47-55, 2017).

(iv) consumers: many of the companies we work with are involved in Fast Moving Consumer Goods, where research has direct consumer benefit, for example in the creation of low fat foods that have high-fat mouthfeel. In addition, the overall aim of the programme is to develop sustainable formulated products and processes; such materials will be better for the environment and consumers.