Characterisation of foam properties using image analysis

The physical properties of a series of model protein, surfactant and protein/surfactant foams were enumerated and investigated using foam conductivity, surface tension, preliminary surface rheology and bulk viscosity measurements. Images of various predetermined stages in the evolution of foam samples were obtained. Foam images were recorded, digitised and analysed using mathematical analysis of image texture. A textural appreciation was achieved by counting bubbles in selected images at key points during the evolution of the foam. Statistical treatment allowed delineation of real and mathematical artefacts generated in textural descriptions of foams. A principal component analysis parameter was identified, which not only corresponded with bubble size but also described bubble shape and occurrence in the texture. Analysis of the data showed correlations between sample images and changes in the structure and the composition of the adsorbed interfacial layer, highlighted using physical measurements