Leibniz Institute researchers uncover how fava bean proteins interact with human tactile cells to influence mouthfeel

Researchers at the Leibniz Institute for Food Systems Biology at the Technical University of Munich have, for the first time, studied how protein nanofibrils derived from fava beans affect human oral tactile cells. These cells, known as mechanoreceptor cells, play a critical role in texture perception by responding to mechanical stimuli like pressure.

The findings, recently published in Foods, could improve the sensory appeal of plant-based foods and support the shift to more sustainable and healthier diets.

As global sales of plant-based foods continue to rise—from US$29.4 billion in 2020 to a projected US$161.9 billion by 2030—there is growing demand for innovations that improve their sensory characteristics. “It is not surprising that there is a strong demand for biomaterials that can enhance the mouthfeel of plant-based food alternatives,” explained Dr Sanjai Karanth, research associate in the Mechanoreceptors junior research group and first author of the study.

Protein nanofibrils are highly organized molecules with unique physicochemical properties that influence food texture. Fava bean nanofibrils, in particular, are promising biomaterials for improving the mouthfeel of plant-based products.

Although their formation and behavior in liquid systems are well-documented, little is known about how these nanofibrils affect human cells under physiological conditions. This gap in knowledge prompted the Leibniz team, led by junior research group leader Dr Melanie Köhler, to explore their interactions with human mechanoreceptor cells.

Using advanced technologies, the researchers found that adding fava bean nanofibrils to a cell culture medium roughened the surface structure of the cells but did not alter their overall elasticity. This initial observation, obtained through atomic force microscopy, prompted further molecular-level investigations.

The study revealed that the nanofibrils influenced the activity of receptor genes involved in texture perception, such as mechanosensitive ion channels (piezo receptors) and fatty acid receptors. Tests on artificial cell membranes also showed that nanofibrils interact with lipids in the membrane, altering elasticity in this model system.

“Although our research is still in its early stages, our biophysical and biochemical results already suggest how nanofibrils can influence the perception of texture and fat,” said Dr Köhler.

The team envisions broad applications for plant-based protein nanofibrils in creating sensorially appealing foods. “We want to deepen our findings through future experiments and sensory studies,” Dr Köhler explained. “In the long run, we aim to develop innovative applications for nanofibrils that improve the texture of plant-based products.”