Formation and stability of foams

Wageningen Food & Biobased Research investigates the formation and stability of foam in food products at the molecular, ingredient, and product levels. Providing insights that allow the prediction and targeted modulation of foam properties.

What is it that makes products such as desserts, cream, cappuccino, beer and bread so popular with consumers? Perhaps it is the creamy mouthfeel that foams provide. Air bubbles also offer opportunities for reducing fat levels in products. However, for manufacturers, foams have one major disadvantage: their quality and stability are difficult to control. How do you ensure that whipped cream is still intact after half an hour? And how do you make an ‘airy’ dessert with reduced sugar contents? Foam formation is a complicated process, influenced by many factors. When frothing milk, for example, not only the fat and protein content have a role; how the milk proteins unfold is important too. Wageningen Food & Biobased Research helps ingredient suppliers, food companies and equipment manufacturers to predict and control the quality and stability of foams. We use an integrated approach that examines foams on multiple levels - from molecule and interface to thin film and foam - and establish the relationships between ingredients, manufacturing processes and end products.

Predicting foam properties

Wageningen Food & Biobased Research offers unique knowledge and research facilities. Our expertise ranges from food chemistry and physics to food technology and modelling. We are one of the very few organisations in the world that combine different techniques to predict foam properties. For example, the drop tensiometer gives us insight into the properties at the air-water interface, and we use the Sheludko-cell to study bubbles between thin films; whether or not to break from such a film tells us something about the foam’s stability. The FoamScan, used for research to the formation and stability of foam, provides insights into the amount of air you can add, changes in the bubble size (distribution) and foam drainage. In addition, we apply X-ray tomography (XRT) to study, three-dimensionally, the distribution of bubble sizes - which affects, for example mouthfeel, appearance and structure of products. Based on our understanding of ingredient behaviour at the molecular level and of foam making processes we develop quantitative design rules to predict, and thereby control, the properties of foams.

Companies can approach us for R&D projects as well as consultancy in all areas of foam (behaviour). We regularly organize meetings for experts in the area of foam development to share their developments and experiences.

Formation and stability of microbubbles

One of our research projects, performed within the TI Food and Nutrition partnership, focusses on the development of foods with reduced fat and increased protein and fibre content. Within this project we study the mechanisms responsible for the formation and (in)stability of tiny bubbles called microbubbles. We also aim to understand the physical and chemical behaviour of microbubbles and how these affect sensory properties such as mouthfeel and creaminess.