39 Bread aeration: A model answer.

G. M. CAMPBELL. Satake Centre for Grain Process Engineering, UMIST, P.O. Box 88, Manchester, UK.

Aerated foods offer great potential for innovative new food products. Bubbles are versatile, cheap, non- fattening and non-toxic, the ideal food ingredients. But effective innovation of aerated food products requires sound understanding of the physical behaviour of bubbles in food systems. Bread is an excellent example of an aerated food, and is arguably the world’s most complex staple food. Breadmaking thus offers an ideal testbed for understanding – if we can understand aeration of dough during mixing, bubble growth during proving and bubble rupture and coalescence during baking, we have the basis of a sound understanding of aerated foods, and the basis of effective product and process innovation. This paper presents an overview of our current understanding of bread aeration during mixing, proving and baking. It highlights some of the current mythology surrounding bread aeration, and makes the case that modelling of aeration processes offers a firm basis on which to evaluate how correct our understanding is. Models require experimental validation; the paper identifies the experimental tools now available to bread aeration researchers.