Different methods of cooking vegetables could vary their effects on dental erosion, a study by researchers at the University of Dundee has found.

A research team led by Dr Graham Chadwick in the School of Dentistry have investigated whether the method of cooking a popular vegetarian dish, Ratatouille, would have any impact on the acidity of the food, and therefore the potential for contributing to dental erosion.

Their research found that, however it is cooked, ratatouille is acidic. But, oven-roasting significantly increases the acidity compared to the more traditional stewed version of the dish, to the point where it is as acidic as some carbonated drinks.

Dr Chadwick said, “The acidity of ratatouille prepared by oven-roasting is the same as that of some carbonated drinks that, when consumed in excess, are believed to contribute to the development of dental erosion.

“The finding that cooking method has an impact on the acidity of food is an interesting and useful tool for dentists when advising patients on ways to reduce their chances of dental erosion.”

The Dundee team’s research was based on reports that people on a vegetarian diet may be more at risk from dental erosion because such a large quantity of the foods they eat, such as fruits and vegetables, tend to be quite acidic in nature.

Dental erosion is caused by the direct contact of acid with the teeth. The acid destroys tooth tissues and can result in severe destruction, leading to the need for expensive and time-consuming dental treatment.

The Dundee team also investigated whether the cooking method had an impact on the acidities of individual vegetables and fruits. They found the cooking method had no impact on the acidity of tomatoes or onions, but roasting resulted in more acidic aubergines, green peppers and courgettes. Red peppers were more acidic when stewed.

The research is published in the current edition of the European Journal of Prosthodontics and Restorative Dentistry. It is one in a series of research projects being carried out at the University looking into the causes of dental erosion.