Throughout history bubbles have been integral to the creation of the finest foods and beverages. Staples such as bread, ice cream, breakfast cereal, cheese, and beer are shaped by this traditionally underappreciated and understudied ingredient. Bubbles in Food is the proceedings of the international conference of the same name held in Manchester, UK in June 1998. The goal of the conference was to bring together a multi-disciplinary group of food industry professionals and academics to consider the issues surrounding bubble research and applications.

The challenges of using bubbles in food products are threefold and common across all food groups:

• How can they be measured?
• How do they behave in specific products?
• How can they be used commercially for maximum benefit and profitability?

Bubbles in Food brings clarity to these challenges by synthesizing the most current research on the issues inherent in them, including bubble size distributions, air contents, surface chemistry, rheology, diffusion, process dynamics, and marketing and consumer preference.

Discussion focuses on four general issues: bubble entrainment and generation; bubble growth and foam stability, bubble measurement and control, and bubbles for sensory and marketing advantage. The editors group papers by theme, rather than food group, to ensure seamless coverage. A comprehensive index allows readers to locate specific foods or issues of interest to them.

Bubbles in Food provides an overview of current food aeration knowledge and research, as well as practical, food-group specific advice. Coverage includes techniques for measuring bubble size distributions, air contents, rheology, foamability and foam stability; mathematical models for prediction of bubble size, air entrainment and bubble growth; effects of emulsifiers, proteins, lipids, sugars and ethanol; and effects of mixing conditions and processing factors.

Bubbles in Food

SECTION I

Bubble Entrainment and Generation

An introduction to bubble mechanics in foods
Entrainment and disentrainment of air during bread dough mixing, and their effect on scale-up of dough mixers
The effect of fermentation on bubble formation and structural properties of an extruded cereal product
Evolution of CO2 bubbles during brewery fermentation
Foaming of ice cream and the time stability of its bubble size distribution
Vapour-induced puffing as an intermediate step in the dehydration of vegetables
Foam generation in a continuous rotor-stator mixer
Combined effects of substrate and process parameters in food foaming processes

SECTION II

Bubble Growth and Foam Stability

Cereal-based Foods

The evolution of bubble structure in bread doughs and its effect on bread structure
The role of wheat proteins and polar lipids in the stabilisation of the foam structure of dough
Modeling bubble growth during proving of bread dough: Predicting the output from the Chopin Rheofermentometer
Simulation of bubble growth in heat processed cereal systems
Prediction of dough volume development which considers the biaxial extensional growth of cells
Physical factors determining gas cell stability in a dough during bread making

Protein-stabilized Foams

Keeping a head: Optimising beer foam performance
Enhancement of bubble surface elasticity by crosslinking agents and their effects on protein foam stability
Foaming and thin film behaviour of commercial caseinate: The effect of lipid content and temperature
Effects of sugars on the foaming of native and dried proteins