Beyond taste buds: texture, sound, and the science of mouthfeel

But let’s leave them for our next conversation. Today, I would like to talk about texture — aka mouthfeel — and the ay it contributes to what we perceive as flavour.

With every morsel of food we consume, our tongue and teeth are there to explore and investigate. The tongue pushes the food towards the teeth, where they chop and break it into smaller pieces. This constant physical processing — poking, prodding, and crushing — sends information to the brain and helps it assess whether the food we are eating is ripe, safe, and enjoyable.

Our ability to appreciate the texture of food is made possible by the oral somatosensory receptors. In addition to the pleasure of eating, these receptors play important roles in our safety and speech. They are capable of detecting mechanical (touch, pressure, vibration), thermal (temperature), and noxious (pain, irritation) stimuli. The receptors convert these physical, thermal, and chemical inputs into electrical signals, which they send as feedback to the brain about the sensory experience we are having.

Modern science distinguishes four main mouthfeel preferences among people*. These categories describe how individuals primarily manipulate and break down food in their mouths and help explain why we prefer certain textures over others.

Chewers enjoy an ongoing sensation of working through a dense, resistant texture. They look for a sense of “fullness” in the mouth that lasts. Typically, they derive great joy from biting into an apple, a steak, or a chewy granola bar.

Crunchers eat more forcefully and aggressively. They seek rapid fracture along with the sound and sensation of things snapping or shattering. Foods like crisps, nuts, raw vegetables, or hard cookies are their favourites.

Smoothers prefer soft, creamy, spreadable textures that coat and spread over the roof of their mouth. They love a smooth and homogenous structure, so foods like puddings, oatmeal, mashed potatoes, and yogurt are their go-to choices.

Suckers enjoy prolonged contact with food. They place it in the mouth and gradually draw out the flavours and juices before chewing or swallowing. Hard candies, lollipops, or chewy chocolate are what they tend to reach for.

Most of us are some combination of these four categories. Perhaps this is why we crave multi-textured foods and why many chefs are preoccupied with incorporating several textures — using, for example, a sprinkle of Maldon salt for crunch or a handful of dried fruits for chew.

Interestingly, the search for optimal mouthfeel or consistency can sometimes reduce flavour intensity. A classic example is sauces. These sticky but essential flavour makers play a crucial role in tying everything together on the plate.

Sauces are commonly made with thickeners such as starches (cornstarch, tapioca), wheat flour, or proteins (eggs, gelatine), which in general have little or no flavour of their own. Therefore, adding too much thickener risks diluting the concentration of flavour. While they are necessary, they must be used with caution.

Another important aspect of texture is its interconnection with our feeling of satiation. Foods that require more effort to break down and chew take longer to eat and digest. As they move along our intestines, they stimulate the release of satiety hormones.

Soft foods, on the other hand, are ingested so quickly that they often fail to reach the parts of the gut that signal “stop eating”. This “softness problem” is now a scientifically substantiated explanation for why ultra-processed foods (UPF) can be so easy to overeat**.

UPFs are engineered to such an extent that the final product is almost pre-chewed. As a result, our brains never receive the proper “I’m full” signal. Have you ever wondered why you can still feel hungry after a bowl of cereal or a fast-food burger? Food texture might be part of the answer.

Texture also comes hand in hand with sound. The cochlea, located in our inner ear, is the auditory receptor shaped like a snail. It is responsible for collecting sound vibrations and communicating them to the brain, which then uses this information to judge the source and quality of the sound.

In terms of food, sound is one of its essential flavour makers. We rarely deem something tasty unless we hear the vigorous sizzle of a steak or the satisfying pop of a beer can. If the food doesn’t sound right from the outset, it is unlikely to be perceived as truly flavourful.

In addition, certain ambient sounds can help put us in the mood for enjoying food. Restaurants are known to curate playlists that carry us through the dining experience — playing the sound of the ocean when serving fish, or French music to heighten the pleasure of eating in a French-style bistro.

*Sharma, Nik (2020). The Flavour Equation, Chronicle Books, San Francisco.

** van Tulleken, Chris (2023). Ultra-Processed People, Cornerstone Press.

Read more about food from Irina Mikhailava: Why aroma dominates flavour