Chocolate has long been a comfort food for many of us, providing a source of happiness and joy in times of stress, sadness, celebration, boredom, and even on a casual Friday night. It’s a versatile treat that can lift our spirits and bring a smile to our faces no matter the occasion.

But why chocolate feels so good?

Scientists have cracked the code behind the irresistible sensation of eating chocolate. They have revealed the physical process that occurs in the mouth when a piece of chocolate is consumed, as it transforms from a solid into a smooth, velvety emulsion that people find hard to resist.

The University of Leeds’ interdisciplinary research team is delving deep into the chocolate-making process with the goal of creating a new generation of luxury chocolates that retain the beloved texture and mouthfeel, but are healthier for consumers to enjoy. By closely analyzing every step of chocolate production, the team hopes to revolutionize the industry with their findings.

The secret to chocolate’s irresistible sensation lies in its lubrication process. As the chocolate melts in the mouth, the fat content plays a crucial role in providing that smooth, creamy texture. However, researchers have found that the solid cocoa particles released during this process are primarily responsible for the tactile sensation of chocolate. This means that the amount of fat present deeper inside the chocolate may not have a significant impact on its overall feel and sensation, potentially opening the door for the development of healthier chocolate options.

According to Professor Anwesha Sarkar of the School of Food Science and Nutrition at Leeds, lubrication science provides valuable insight into how food feels in the mouth. Using this knowledge, it is possible to design foods with improved taste, texture, and health benefits.

“If a chocolate has 5% fat or 50% fat,” according to professor, “it will still form droplets in the mouth and that gives you the chocolate sensation. However, it is the location of the fat in the make-up of the chocolate which matters in each stage of lubrication.”

The results say “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 research, which was published in the journal ACS Applied Materials and Interface, did not analyze the flavor of chocolate. Instead, an emphasis was placed on its feel and texture.

Using a high-end brand of dark chocolate, tests were carried out on a synthetic, 3D tongue-like surface created by Leeds University. The investigation was conducted using analytical tools from the engineering discipline of tribology, which included in situ imaging.

Tribology is the study of how surfaces and fluids interact, the degrees of friction between them, and the function of lubrication: in this example, saliva or chocolate liquids. All of these things happen in the mouth when someone eats chocolate.

When chocolate touches the tongue, a fatty film is released that coats the tongue and other parts of the mouth. This fatty coating is what gives chocolate its smooth mouthfeel throughout the whole eating experience.

“With the understanding of the physical mechanisms that happen as people eat chocolate,” adds lead author Dr. Siavash Soltanahmadi, “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.

According to the findings of this research, it is possible for manufacturers to create dark chocolate with a lower overall fat content while still maintaining the desirable texture and sensation of eating chocolate.

In order to provide the desired self-indulgent sensation without adding too much fat to the chocolate’s body, they think dark chocolate may be created in a gradient-layered architecture with fat coating the surface of chocolates and particles.

The study’s physical techniques could have broader applications beyond chocolate, as it could be used to investigate other foods that undergo a phase change, such as transforming from a solid to a liquid. Food items like ice cream, margarine, and cheese could potentially benefit from this research and be further examined for texture and mouthfeel improvements.

Image Credit: Ben Kilb/Bloomberg via Getty Images