Physics behind perfect pancake may help save eyesight

London: Understanding how to make perfect pancakes could help improve surgical methods for treating glaucoma - eye disease which may result in damage to the optic nerve and vision loss, scientists say.

The appearance of pancakes depends on how water escapes the batter mix during the cooking process and this varies with the thickness of the batter, researchers said.

According to scientists at the University College London (UCL), understanding the physics of the process can help perfect pancake making and give important insights into how flexible sheets, like those found in human eyes, interact with flowing vapour and liquids.

"We've discovered that the variations in texture and patterns result from differences in how water escapes the batter during cooking and that this is largely dependent on the thickness and spread of the batter," said Ian Eames, Professor of at UCL Engineering.

The study compared recipes for 14 different types of pancakes from across the world including the Canadian ploye and Malaysian lempeng kelapa.

For each, the team analysed and plotted the aspect ratio, ie the pancake diameter to the power of three in relation to its volume of batter, and the baker's percentage which is the ratio of liquid to flour in the batter, ie the thickness of the batter.

To explore how these ratios influence the textures and patterns of pancakes, the scientists made batters with a fixed amount of flour and egg but different amounts of milk.

Pancakes were made using the batters in the same pan, at the same heat and without fat.

The scientists found that thick batters form pancakes with irregular craters on the bottom surface.

Water vapours released during cooking get trapped, unevenly lifting the pancake from the pan. Islands form on top surface as the pancake isn't a uniform thickness.

Thinner batters form pancakes with an even colour on the bottom surface as water vapour is released smoothly from the base as it cooks. This effect is also seen in small pancakes irrespective of the thickness of the batter.

The thinnest batters form pancakes with an even coloured bottom surface which is dotted with dark spots. Water vapours escape smoothly across the bottom surface and through channels in the batter.

"We work on better surgical methods for treating glaucoma, which is a build-up of pressure in eyes caused by fluid," said Professor Peng Khaw, from the UCL Institute of Ophthalmology.

"To treat this, surgeons create an escape route for the fluid by carefully cutting the flexible sheets of the sclera," Khaw said.

"We are improving this technique by working with engineers and mathematicians. It's a wonderful example of how the science of everyday activities can help us with the medical treatments of the future," he added.

The study was published in the journal Mathematics TODAY.