Air inclusion into a model cake batter using a pressure whisk: Developmentof gas hold-up and bubble size distribution

This paper investigates the development of gas hold-up (that is, gas volume fraction) and bubble size distribution in a model cake batter, which is ae rated in a pressure whisk. With increasing aeration time, the hold-up was f ound to pass through a maximum before approaching a uniform steady state va lue. A mathematical model that describes this profile has been developed. B ubble size distribution was found to be adequately described by a log norma l distribution function with mean size varying between 20 and 50 mum. Highe r pressures were found to increase hold-up and mean bubble size, whereas hi gher whisk speeds reduced the time required to achieve a given hold-up and the final mean bubble size.