R&D Profile: Colloid Particles for Advanced Control of Product Appearance
Appearance is an important factor determining the perceived product quality and freshness. Consumers often develop strong associations through appearance, and often base their pre-purchase judgments on the appearance of the product. Colloid based technologies provide a powerful approach to control product appearance and can enable novel product appearance.
Dr. Krassimir Velikov, Research Manager, Food Structural Design, Unilever Food and Health Research Institute-part of the Unilever R&D division in Vlaardingen, the Netherlands, tells NWN about his upcoming presentation at Nanotech 2008 in Boston.
Appearance is an important factor determining the perceived product quality and freshness. Consumers often develop strong associations through appearance, and often base their pre-purchase judgments on the appearance of the product. Colloid based technologies provide a powerful approach to control product appearance and can enable novel product appearance. Custom designed colloidal particles and colloidal emulsions from food grade ingredients offer great opportunities for fine tuning of product appearance through manipulation of light absorption and scattering due to their strong size and morphology dependent optical properties. The unique combination of material properties control and structure design in the application of colloidal dispersions offer a step change in product functionality control. Besides controlling the basic attributes of product appearance, more complex optical effects such as colour matching fortification or angle dependant colours can be achieved. Often the use of colloids offers additional advantages in terms physico-chemical stability, taste, and bioaccessibility. For any future commercialisation, the cost in comparison to benefit and performance as well as all safety aspects and consumer acceptance need to be evaluated in detail to assess the full potential of this technology. This approach is valid not only for food systems, but also for other applications such as home and personal care products, drug formulation, agricultural compositions, and animal feed.
The market drive for novel products and product differentiation will promote further developments in the area of product appearance control. Since this is a very complex area, knowledge on material properties (suitable choice of ingredients), physico-chemical properties (interaction during processing and storage) and optical properties of matter, as defined by micro and nanostructures, will be very important for successful application. Furthermore, the ability to control these aspects will be crucial for tuning, enhancing or design novel product appearance. The ability to control appearance through structure and degree of order in products can give new possibilities for novel product design without changing the initial composition (nutritional profile in case of foods). Future developments may progress in direction to enable novel product formats that were previously impossible to make due to unwanted changes in appearance, enhancing white colour without using whiteners, and enhancing colour by using more stable and environmentally friendly pigments. Finally, when addressing appearance an integrated approach to product functionality is required. In this approach all aspects of the product functionality (e.g. stability, texture, taste, and ingredients bioavailability) are simultaneously considered and addressed to achieve a balanced and consumer acceptable solution.
1. Advanced colloid technologies for control of product appearance, K.P. Velikov, A. K. Popp, L. Flendrig, E. Pelan, New Food, 1, 2008.