The signals are decoded by the brain, and we perceive the taste of the food, which could be one of five distinct qualities: sweet, sour, salty, bitter and umami.
During this critical period of food manipulation, the tongue is sampling chemicals in the food, and when food chemicals activate taste receptors, signals are sent from the taste receptors to processing regions of the brain. Once a food enters the mouth, the tongue aids in the manipulation of the food, assisting breakdown and bolus formation before swallowing the food.
The primary organ responsible for the sense of taste is the tongue, which contains the biological machinery (taste receptors) to identify non-volatile chemicals in foods and non-foods we place in our mouth. The sense of taste presumably evolved to inform us about the nutritious or toxic value of potential foods. The likely mechanism linking fatty acid taste insensitivity with overweight and obesity is development of satiety after consumption of fatty foods. There appears to be a coordinated bodily response to fatty acids throughout the alimentary canal those who are insensitive orally are also insensitive in the gastrointestinal tract and overconsume fatty food and energy. The implications of fatty acid taste go further into health and obesity research, with the gustatory detection of fats and their contributions to energy and fat intake receiving increasing attention. Therefore, overall, with the exception of an independent perception, there is consistent emerging evidence that fat is the sixth taste primary. It has also been established that oral exposure to fat via sham feeding stimulates increases in blood TAG concentrations in humans. Others suggest that the fatty acid taste component is at detection threshold only and any perceptions are associated with either aroma or chemesthesis. Whether fatty acids elicit any direct perception independent of other taste qualities is still open to debate with only poorly defined perceptions for fatty acids reported.
#HOW MANY TASTE BUDS DO HUMANS HAVE SERIES#
Once the receptors are activated by fatty acids, a series of transduction events occurs causing the release of neurotransmitters towards afferent fibres signalling the brain. The most likely fatty acid receptor candidates located on TBC are CD36 and G protein-coupled receptor 120.
Indeed, psychophysical studies have confirmed that fatty acids of varying chain length and saturation are orally detectable by humans. Following the same logic, the breakdown products of fat being fatty acids are the likely class of stimuli for fat taste. The breakdown products of the macronutrients carbohydrates (sugars) and proteins (amino acids) are responsible for the activation of sweet and umami tastes, respectively. For fat to be considered as one of the taste primaries in humans, certain criteria must be met including class of affective stimuli, receptors specific for the class of stimuli on taste bud cells (TBC), afferent fibres from TBC to taste-processing regions of the brain, perception independent of other taste qualities and downstream physiological effects. Taste is the chemical sense responsible for the detection of non-volatile chemicals in potential foods.