This Is Why Chocolate Feels So Good to Eat, According to Science

Everyone knows that chocolate tastes delicious, but a group of researchers has been looking into why having a mouthful of chocolate feels so good too. 

A team from the University of Leeds’ School of Food Science and Nutrition and its School of Mechanical Engineering have determined that part of the reason eating chocolate is so satisfying is because of the way its fats interact with various parts of our mouths. 

That last sentence may sound unappealing, but it’s apparently true. In a study, which has been published in the journal ACS Applied Materials and Interfaces, the Leeds researchers explained that when those bites of chocolate hit our tongue, a “fatty film” — their words — is released into our mouths, providing an irresistibly smooth sensation as we chew. 

The team hopes that their research into how the fats in chocolate interact with saliva could be used to develop a healthier version that feels just as good to eat. 

“If a chocolate has 5% fat or 50% fat, it will still form droplets in the mouth, and that gives you the chocolate sensation,” Anwesha Sarkar, a professor at the School of Food Science and Nutrition, said in a statement. “However, it is the location of the fat in the make-up of the chocolate which matters in each stage of lubrication, and that has been rarely researched.” 

Sarkar said that they have determined that, regardless of the amount of fat in the chocolate, the “fat layer” needs to be on the outside layer of the candy in order to elicit the same enjoyable mouthfeel.

Before you ask: no, Sarkar and the rest of the team didn’t tear into bag after bag of Hershey’s Miniatures. Their methodology involved an unnamed luxury brand of dark chocolate and an artificial “tongue-like surface” that was 3D printed at the university. 

That, er, replica tongue was co-developed in late 2020 by scientists at the University of Leeds and the University of Edinburgh. That team made silicone molds of 15 adults’ tongues, then used computer simulations to recreate the size, shape, and distribution of the papillae, the tiny bumps that give our tongue its rough texture. After that, it was 3D printed using a soft polymer designed to mimic the softness, elasticity, and “wettability” of a human tongue. 

That tongue’s ability to replicate what happens when chocolate and saliva combine in our mouths was crucial to the team’s research.

“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,” lead researcher Dr. Siavash Soltanahmadi said. “Our research opens the possibility that manufacturers can intelligently design dark chocolate to reduce the overall fat content.” 

Now we really are going to tear into some Hershey’s Miniatures. For science.