Leeds University scientists reveal why chocolate feels so good

Scientists say the fat near the outside of a piece of chocolate is key to it feeling smooth. Credit: PA

Researchers say they have discovered the reason why chocolate feels so good to eat.

A team of scientists at the University of Leeds analysed the physical process that takes place when chocolate breaks down in the mouth.

They found the fat in melting chocolate helps to make the texture so appealing.

By analysing each of the steps in the process, researchers hope their findings will lead to the development of luxury chocolate with the same feel and texture that is healthier to eat.

The team said when chocolate is in contact with the tongue, it releases a fatty film that coats the tongue and other surfaces in the mouth, making it feel smooth the whole time it's in the mouth.

According to the study, the chocolate sensation arises from the way the chocolate is lubricated, either from ingredients in the chocolate itself, saliva or a combination of the two.

Almost as soon as chocolate comes into contact with the tongue, fat has a key role to play. After that, solid cocoa particles are released and they become important in terms of the physical sensation.

This means that fat deeper inside the chocolate could be reduced without the feel or sensation of chocolate being affected.

Tests were conducted using dark chocolate Credit: Alamy/PA

Anwesha Sarkar, a professor at Leeds University, said: “You can use that knowledge to design food with better taste, texture or health benefits.

“If a chocolate has 5% fat or 50% fat it will still form droplets in the mouth and that gives you the chocolate sensation.

“We are showing that the fat layer needs to be on the outer layer of the chocolate, this matters the most, followed by effective coating of the cocoa particles by fat, these help to make chocolate feel so good.”

The study did not look at how chocolate tastes, and instead focused on physical sensation and texture, using a luxury brand of dark chocolate on an artificial tongue-like surface designed at the university.

Lead researcher Dr Siavash Soltanahmadi said: “With the understanding of the physical mechanisms that happen as people eat chocolate, we believe that a next generation of chocolate can be developed that offers the feel and sensation of high-fat chocolate yet is a healthier choice.

“Our research opens the possibility that manufacturers can intelligently design dark chocolate to reduce the overall fat content."

The researchers believe the physical techniques used in the study could be applied to the investigation of other foodstuffs that undergo a phase change, such as ice-cream, margarine or cheese.

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