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The key to making bread is kneading the dough, as an even distribution of gas bubbles gives the bread a good texture. Unfortunately for consistency, the optimum amount of kneading required varies with different batches of flour. The University of Manitoba in Winnipeg is bringing science into this art (WO 2004/19027). It has developed a device in which the dough is clamped between two aluminium plates, one of which is vibrating at around 50 kilohertz. The other plate measures the ultrasonic vibrations that travel through the dough. The bubbles scatter and slow the ultrasound, so monitoring the amplitude and velocity of the vibrations reveals how much more kneading is required.