In this work, a methodology to evaluate foaming capacity and stability is proposed. With this method the foam volume decay is followed and the overrun [(foam volume-solution volume)/solution volume] plotted against time. The integral of overrun decay for a fixed period was tried out as a single parameter to describe foam properties, i.e. foaming capacity and foam stability. It was concluded that using this single parameter; the foaming stability index (F.S.I.)(t), the application of statistical experimental design methodology to optimise foaming becomes straightforward. As an example of an application of this method, the denaturation extent of the protein was optimised to improve the foaming properties of Lupin protein isolate.