Why chocolate feels so good – it’s all in the lubrication – Zoo House News
Scientists have deciphered the physical process that takes place in the mouth when a piece of chocolate is eaten, transforming it from a solid to a smooth emulsion that many people find absolutely irresistible.
The University of Leeds’ interdisciplinary research team hopes that analyzing all the steps will lead to the development of a new generation of luxury chocolates that have the same feel and texture but are healthier to consume.
In the moments when it’s in the mouth, the chocolate sensation comes from the way the chocolate is lubricated, either by ingredients in the chocolate itself or by saliva, or a combination of both.
Fat plays a key role almost immediately when a piece of chocolate comes into contact with the tongue. Thereafter, solid cocoa particles are released and they become important in terms of tactile feel, so fat deeper in the chocolate plays a more limited role and could be reduced without affecting the feel or sensation of chocolate.
Anwesha Sarkar, Professor of Colloids and Surfaces at the School of Food Science and Nutrition in Leeds, said: “The science of lubrication provides mechanistic insights into how food actually feels in the mouth and has health benefits.
“If a chocolate is 5% fat or 50% fat, it still forms droplets in your mouth and that gives you the chocolate feel. However, it is the position of the fat in the composition of the chocolate that is important at each stage of lubrication, and this is poorly understood.
“We show that the fat layer has to be on the outer layer of the chocolate, that’s most important, followed by an effective coating of the cocoa particles with fat that helps chocolate feel so good.”
The study, published in the journal ACS Applied Materials and Interface, did not address the question of how chocolate tastes. Instead, the investigation focused on its feel and texture.
Tests were conducted using luxury brand dark chocolate on a 3D artificial tongue-like surface designed at the University of Leeds. Researchers used analytical techniques from a technical field called tribology to conduct the study, which also included in situ imaging.
Tribology is about how surfaces and liquids interact, how much friction there is between them, and the role played by lubrication: in this case, saliva or liquids from the chocolate. These mechanisms all take place in the mouth when chocolate is eaten.
When chocolate comes in contact with the tongue, it releases a film of fat that coats the tongue and other surfaces in the mouth. This fatty film ensures that the chocolate feels smooth in the mouth the entire time.
dr Siavash Soltanahmedi, from the School of Food Science and Nutrition in Leeds and lead researcher on the study, said: “By understanding the physical mechanisms at play when chocolate is eaten, we believe a next generation of chocolate can be developed that has the feel and offers the sensation of high-fat chocolate while still being a healthier choice.
“Our research opens up the possibility that manufacturers can intelligently design dark chocolate to reduce total fat content.
“We believe that dark chocolate can be made in a gradient layer architecture, with fat covering the surface of chocolate and particles to provide the desired indulgence experience without adding too much fat into the body of the chocolate.”
According to research from business intelligence agency MINTEL, revenue from chocolate sales in the UK is expected to increase over the next five years. Revenue is projected to grow 13% to £6.6 billion between 2022 and 2027.
Researchers believe the physical techniques used in the study could be applied to the study of other foods that undergo a phase change, in which a substance changes from a solid to a liquid, such as: B. ice cream, margarine or cheese.
This project has received funding from the European Research Council under the European Union’s Horizon 2020 research and innovation programme.