Chemical engineer reveals the secret ingredient of the perfect sandwich

Speaking at an Institution of Chemical Engineers’ (IChemE) lecture, Professor Grant Campbell said that bubbles in bread are as important for making a good sandwich as its filling, due to the unique composition of wheat.

“Bread is special because of its bubbles. It’s got these bubbles because wheat, when mixed with water, salt and yeast is the only cereal that can trap the carbon dioxide and give us raised bread.

“That raised bread makes for soft bread and it’s soft because of the bubbles. Different breads are distinguished by different aerated structures. It’s one of the reasons why brown or wholemeal bread is less suitable for making tasty sandwiches – the bran pops the bubbles.

“Chemical engineers are working to find a way of getting bran into bread recipes without popping the bubbles. By doing this we will create a healthier bread without sacrificing the tastiness. Nutritionists have been telling us to eat more wholemeal bread for decades but we still prefer white bread because it tastes better” explained Campbell.

Speaking at Birmingham University to an audience of chemical engineers, scientists and students, Campbell was awarded IChemE’s Frank Morton medal – recognising his outstanding service to chemical engineering education.

“Bubbles have made wheat the world’s most important food crop. If you took all the engineers that have ever lived and asked them to recreate such an appealing food structure, at such a price that most people in the world could afford to eat it every day, they wouldn’t come up with anything as remarkable as bread,” said Campbell.

“Bread is the world’s most important food and wheat is the king of grains because of its unique ability to give us bubbly bread,” he concluded.

Campbell, based at the University of Manchester, also explained the key role bubbles play in other foods and drinks, including chocolate, champagne and meringue.