Scientists have finally found the perfect shape for chocolate, which raises its flavor to its maximum power when we taste it in the mouth. Question of metamaterials.
Researchers at the University of Amsterdam have used physics and geometry to find out how chocolate is more palatable. In this way they have discovered that the spiral shape of the piece of chocolate, obtained by means of a 3D printer, is the ideal one to achieve maximum flavor.
Chocolate is a food that is obtained by mixing sugar with two products that derive from the manipulation of cocoa beans: cocoa mass and cocoa butter, considered by tradition to be the “food of the gods”.
After making a dough containing 72% cocoa, the Amsterdam scientists printed several different shapes of chocolate and then subjected the obtained models to mechanical tests, to discover how many pieces would break in the mouth when consumed.
They then tested the different printed forms of chocolate with a group of 10 volunteers and found that the more complex the structure of the chocolate, the more popular it is with those who taste it.
They weren’t too surprised by this result, as previous research has known that breaking food up in the mouth increases the flavor of the meal, especially because of the familiar crunch it produces.
It has also been speculated in the past that the pleasure of breaking food in the mouth may be due to an unconscious association between crunchy and fresh, compared to soft food, which could be related to a possible bad state.
According to various studies, this subjective impression would surely have helped our ancestors to pursue more nutritious and safer foods, since the most remote past of our species.
The new research, published in the journal Soft Matterdemonstrates that the mouthfeel of an edible substance can be designed, just like the properties of many other materials.
For this it is necessary to create metamaterials, that is, materials that are not found in nature, but are carefully constructed in the laboratory. The construction material chosen in this case is not wood, concrete or glass, but chocolate.
However, chocolate is not an easy material to work with. Simply heating and cooling it can turn soft chocolate into much more brittle tempered chocolate, or vice versa, the researchers note in a statement.
Therefore, the first challenge for this study was to get the construction material under control. He did this by heating it very carefully, adding some cold chocolate, then cooling it some more… and then putting it into a 3D printer.
This procedure allowed him to print virtually any shape of chocolate material he wanted, while ensuring that the base material always had the same properties.
This video explains the development of chocolate research by a member of the research team, Corentin Coulais.best spirals
The first form of edible material scientists experimented with was an S-shaped chocolate with lots of twists. The goal was to test how this material would break and how that break would be experienced in the mouth.
Having shown that this experience can be engineered, the researchers tried a few different ways, looking for a structure in which the number of cracks could be programmed into the chocolate metamaterial.
They discovered that the spiral-shaped chocolate metamaterials they have quite interesting and adjustable properties that take their flavor to paroxysm.
The number of turns not only directly controls the number of cracks when the material is mechanically pressed; but the test panel was also able to clearly distinguish the cracks that occur when eating the chocolates.
In addition, the recordings showed that the sound chocolates make when bitten reflects the number of cracks, adding to a more enjoyable eating experience.
The final question the researchers asked themselves was: is designing a pleasurable dining experience a matter of trial and error, or can palatable edible materials be designed and refined before they are created?
The researchers found that with a well-chosen mathematical modelcertain shapes of chocolate can be optimized with respect to, for example, their resistance to breaking when bitten from certain directions.
The discovery is important because the design of edible metamaterials has not been studied before.
The new research opens the door to ways to design foods that are enjoyable to eat and, more generally, to design materials that optimize the interaction between humans and matter, the researchers conclude.
Edible mechanical metamaterials with designed fracture for mouthfeel control. Andre Souto et al. Soft Matter, 21 Mar 2022. DOI: https://doi.org/10.1039/D1SM01761F