New Insights Into Food Texture Sensation

Thursday, August 18th, 2016 | 1379 Views

New findings on how food viscosity and hardness are determined could provide more insights into refining the texture of foods, enhancing their appeal and satiety.

Researchers have discovered a cell located in the fruit fly’s main taste organ that may play a crucial role in food texture sensation.

Containing a transmembrane channel-like (TMC) protein located on the cell surface, this previously-undiscovered neuron in flies is similar to a TMC protein that is important in humans for hearing. Research suggests that the TMC protein may be an important component of a mechanosensor that exists in flies for taste, and in humans for hearing.

“This work raises the possibility that one or more members of the human TMC protein family might be expressed in the human tongue and function in the sensation of food texture,” said lead author Craig Montell, biologist at the University of California.

Using hydroxypropyl cellulose (HPC) to control levels of food viscosity without modifying intrinsic food tastes, the experiment explored how viscosity of liquid food influenced feeding behaviour.

The research team found that the bristles on the end of the flies’ taste organ bent when they came into contact with HPC, depending on how hard the sucrose substrate composition was. These bristles, located on the outside of the flies’ taste organ, allow the insects to assess food texture before eating.

The food texture discrimination was found to depend upon a previously unknown multidendritic neuron, and was activated on a scale according to the degree of texture of the sucrose. Further analysis revealed that the single TMC protein plays a part in sensing two main characteristics of food — hardness and viscosity. Appeal of the food decreased if the sucrose-containing substrate was too sticky, soft or hard.

The study results place Drosophila flies’ taste system as a model for further research into the cellular and molecular mechanisms that allow an animal to sense food texture.

Food texture has a large effect on food preferences, but the mechanosensory cells and key molecules responsible for sensing the physical properties of food still remain unclear. This discovery may help unravel the mechanisms of action responsible for texture and taste in humans.