02 Jun 2023
Survival: Taste is one of the body’s senses. Its fundamental role is to allow us to get nutrients and survive by sampling the chemical makeup of foods and beverages for nutrient content, palatability and potential toxicity.
Appetite regulation: Taste also guides our appetites and triggers physiological processes for absorbing nutrients and adjusting metabolism.
Enjoyment and meaning: As one aspect of flavour alongside smell, our sense of taste plays a role in our enjoyment of food, cultural identity and social connection, making it an important aspect of our daily lives.
When we eat, chewing and saliva help break down the food into various chemical compounds. These compounds, called tastants, are sensed by taste buds on the tongue, soft palate, pharynx and gut. (Roper et al. 2017)
Zoom in: Each taste bud has its own specialised squad of 50 to 100 taste cells, arranged in clusters that look a bit like a garlic bulb. Each taste cell is a sensory receptor dedicated to sensing specific food compounds that produce one of the five basic tastes:
2. To the brain!
Information from taste buds is conveyed to neurons in the central nervous system. How signals discriminating between sweet, sour, salty, bitter, umami and possibly other tastes are encoded is not entirely known and subject of debate. (Roper et al. 2017)
But it’s more complex than that….
More than 5 tastes?
Taste buds in the gut: Taste receptors are present not only in the mouth but in the gastrointestinal tract and many other organs in the body. They are involved in adjusting digestive processes and metabolism, like the speed of gastric emptying or the regulation of blood glucose levels. (Ekstrand et al. 2017)
Emerging research suggests that genetic predisposition and non-genetic factors such as life stage, eating behaviour and microbiota influence our taste perception.
Variations in the genes encoding taste receptors can influence our perception of taste and food preferences.
Bitter taste: You might have heard of so-called “super-tasters” who intensely taste bitter compounds. That’s because they carry two copies of the tasting PAV variant (genotype PAV/PAV). People carrying one copy of the tasting variant are medium-tasters, while non-tasters carry two copies of the non-tasting variant called AVI.
Umami taste: There is evidence that differences in the perception of umami are common among individuals, with variations up to five-fold. Similar to bitter taste perception, a fraction of the population may carry “non-taster” gene variants for umami, but more research is needed.
Sour taste: One study suggests that genetic factors may be more important than environment to determine the pleasantness and intensity of sour taste. (Chamoun et al. 2021)
Eating behaviour: People with a higher sensitivity to bitter taste may avoid eating bitter-tasting foods such as cruciferous vegetables and leafy greens, which provide many health-promoting compounds.
Variations in the composition of microbes in the mouth may also underlie differences in how we taste food. This research is just emerging and ongoing!
Zoom in: The mouth hosts hundreds of microbes, making it the second most diverse microbiota of the human body after the gut. The tongue, especially, forms a unique site for the accumulation of saliva and microorganisms.
Taste perception & oral bacteria: In recent years, several studies have built up evidence for a close association between taste perception and specific oral bacteria. In some research, the presence of specific bacteria in the tongue film was linked to an increased taste sensitivity, especially to bitterness. For example, super-tasters and non-tasters had different microbial compositions in the tongue. (Cattaneo et al. Scientific reports. 2019)
How? Researchers suggest that microbes in the mouth may influence taste perception and food preferences through multiple mechanisms:
(1) By degrading food compounds and producing secondary metabolites
(2) By creating a physical barrier through biofilm formation that can limit the access of tastants to their receptors.
(3) By regulating the expression of taste receptors genes
On top of biological predispositions, our environment and exposure to different foods can influence taste perception. One study found that frequent exposure to sweetened soft drinks changed sweet taste perception and increased the preference for sweet among individuals who originally disliked sucrose. A twin study demonstrated that environment was more influential than genetics on salt taste. (Kershaw et al. 2018)
Our taste system is changeable and subjective to learning and experience.
Don’t let one bad experience with a food (like broccoli or mushrooms!) deter you from eating it all together. There are always more ways to eat it that might please your taste buds.
Reality check: Here are all the tips we found through research and talking to people about taste. They are general ideas to make your own and adapt depending on your needs and reality. For many, busy lives or a limited budget can challenge paying attention to taste.
The demand for tasting educational programs is on the rise, with industries like wine, tea, coffee and chocolate leading the way. Understanding taste can create a whole new perspective on eating a meal and enhance our appreciation of food. It encourages us to explore food in different forms and preparations, beyond the simplistic notion of good and bad taste.
In practice: Explore the taste of whole plant foods too by talking taste and flavour with those around you and connecting with food enthusiasts, farms and agricultural organisations who are passionate about the vibrant flavours of fresh produce.
2. Taste exposure and variety: Try foods many times in different forms
Researchers suggest at least 10 exposures to a food before determining your true preference. It works by a process of familiarisation and learned safety. Prolonged exposure could produce physiological changes that make the foods more enjoyable. (Schier et al. 2019)
3. Positive associations: Slow down and engage
Our taste system has some degree of flexibility. Foods that are initially aversive, like bitter-tasting vegetables, can develop positive associations.
Factors influencing taste