A healthier you
Our sense of taste has evolved to encourage the consumption of nutrients, and to avoid the ingestion of dangerous substances.
However, today, the positive experience of sweet and salty taste can lead to overconsumption, and detrimental effects on health. Conversely, bitterness and acidity can also prevent some individuals from consuming healthier foods such as bitter tasting green vegetables.
How many basic tastes are there?
There are five basic tastes: sweet, salt, bitter, acid and umami. Research has also suggested that other ‘tastes’ my exist, in particular ‘fat’ and ‘metallic’.
Up until recently it was thought that fat and metallic are perceived by textural receptors in our mouths but a growing body of evidence suggests that taste receptors may also be responsible.
Creating a Taste Map
In this research, we will give samples of each of the tastants (sweet, salty, bitter, sour and umami) to people to taste and we will record the location of activation in the taste cortex part of the brain to create a Taste Map. This can be done by using ultra high resolution functional magnetic resonance brain imaging.
How we sense taste
When a food or drink is consumed, the sapid molecules dissolve into the saliva and enter the taste pore of the taste bud on the tongue.
Taste buds are distributed across the tongue on little raised protrusions called papillae; you can see these if you look closely at your own tongue or someone else's. There are three types of papillae that contain taste buds, circumvallate, foliate and fungiform. The number of papillae each of us has varies between individuals. Circumvallate papillae are the largest of the papillae located on the back of the tongue and are innervated by the glossopharyngeal nerve. Foliate papillae are ridges and grooves towards the posterior part of the tongue and are innervated by the facial and glossopharyngeal nerve. Fungiform papillae are mushroom shaped, present most densely at the tip of the tongue and are innervated by the facial nerve. Research has linked a higher number of fungiform papillae on the tip of our tongue with higher taste sensitivity.
Each papillae houses lots of taste buds and within each taste bud there are between 50 – 150 taste receptor cells. Each taste bud has a taste pore which allows taste molecules to enter the taste bud when you eat or drink. Recent research suggests that each taste receptor cell is specifically ‘tuned’ to one specific taste. Once activated by a taste, the receptor cell sends information to the gustatory cortex in the brain via the afferent nerve (glossopharyngeal or facial).
Please watch the video demonstrating the details below:
Using ultra high field strength functional magnetic resonance brain imaging techniques, the project TASTEMAP will look closely at the gustatory cortex and map where the five basic tastes are processed…something never been done before.
UNDERSTANDING INDIVIDUAL VARAIBILITY WITH TASTE PERCEPTION
Using imaging together with behavioural measures we are investigating the alterations in brain structure and function with taste phenotype.
- Title: An automated method to detect and quantify fungiform papillae in the human tongue: Validation and relationship to phenotypical differences in taste perception. Authors: Eldeghaidy, S., Thomas T, Skinner, M., Ford, R., Giesbrecht, T., Thomas, A., Hort, J., Francis, S., 2018 Journal: Journal of Physiology and Behaviour
- Title: Variation in illusionary taste response across thermal tasters. Authors: Skinner, M., Eldeghaidy, S., Ford, R., Giesbrecht, T., Thomas, A., Francis, S., Hort, J, 2018
Journal: Journal of Physiology and Behaviour
- Title: Investigating the oronasal contributions to metallic perception. Authors: Skinner, M., Lim, M., Tarrega, A., Ford, R., Linforth, R., Thomas, A. & Hort, J, 2017 Journal: International Journal of Food Science and Technology
- Brain response to fat could determine future path in tackling obesity Date: 26-Sep-2016
- ELDEGHAIDY, S., MARCIANI, L., HORT J., HOLLOWOOD T., SINGH, G., BUSH, D., FOSTER, T., TAYLOR, A.T., BUSCH, J., SPILLER, R.C., GOWLAND, P.A., and FRANCIS, S.T., 2016. Prior consumption of a fat meal in healthy adults modulates the brain’s response to fat. Journal of Nutrition, published online ahead of print: doi: 10.3945/jn.116.234104
- HORT, J., FORD, R., ELDEGHAIDY., S and FRANCIS, S.T. 2016 Thermal tasterstatus : Evidence of cross-modal integration. Human Brain Mapping.
- FRANCIS, S. and ELDEGHAIDY, S. 2015 Imaging methodologies and applications for nutrition research: what can functional MRI offer? Proceedings of the Nutrition Society. 74(2), 89-98.
- Food Science and Technology Magazine, published by the Institute of Food Science and Technology
Title: Trends in food sensory science Date: 02/03/2015
- ELDEGHAIDY, S., HOLLOWOOD, T., MARCIANI, L., HEAD, K., BUSCH, J., TAYLOR, A.J., FOSTER, T.J., SPILLER, R.C., GOWLAND, P.A., FRANCIS, S. and HORT, J., 2012. Does fat alter the cortical response to flavor? Chemosensory Perception. 5(3-4), 215-230
- CHEN, X., GABITTO, M., PENG, Y., RYBA, N.J. and ZUKER, C.S. 2011. A gustotopic map of taste qualities in the mammalian brain. Science. 333(6047): 1262–1266
- ELDEGHAIDY, S, MARCIANI, L, PFEIFFER, J, HORT, J, HEAD, K, TAYLOR, AJ, BUSCH, J, SPILLER, R, GOWLAND, PA and FRANCIS, S, 2011. Use of an Immediate Swallow Protocol to Assess Taste and Aroma Integration in fMRI Studies Chemosensory Perception. 4(4), 163-174.
- ELDEGHAIDY, S., MARCIANI, L., MCGLONE, F., HOLLOWOOD, T., HORT, J., HEAD, K., TAYLOR, A. J., BUSCH, J., SPILLER, R. C., GOWLAND, P. A. and FRANCIS, S. T., 2011. The cortical response to the oral perception of fat emulsions and the effect of taster status: J Neurophysiol J Neurophysiol. 105(5), 2572-81
- SANCHEZ-PANCHUELO, R.M., FRANCIS, S., BOWTELL, R. and SCHLUPPECK, D., 2010. Mapping human somatosensory cortex in individual subjects with 7T functional MRI. Journal of Neurophysiology. 103(5), 2544-2556
- MARCIANI, L., PFEIFFER, J.C., HORT, J., HEAD, K., BUSH, D., TAYLOR, A.J., SPILLER, R.C., FRANCIS, S. and GOWLAND, P.A., 2006. Improved methods for fMRI studies of combined taste and aroma stimuli. Journal of Neuroscience Methods. 158(2), 186-94
Prof Sue Francis
Phone: 0115 846 6518 Email: firstname.lastname@example.org
Dr Sally Eldeghaidy
Phone: 0115 8466003 Email: Sally.Eldeghaidy@nottingham.ac.uk