Scientists say they have discovered specific neurons in the brain that recognize five levels of taste: salty, bitter, sour, sweet and pleasant.
By Dr. Ashaq Hussain
While naming the five senses, it can be easy to forget taste. After all, sight, sound, touch and smell are happening almost all the time. Taste waits until we put something in our mouths. But taste is extremely important. It helps us determine whether something is good to eat or not, sweet, salty or the savory, Bitter or really sour?
According to a study, not all people enjoy the taste of food in the same way. Some of us want strong coffee in the morning and some of us object to it. We react differently to different foods, and scientists say it's not a matter of individual or personal preference. No doubt taste is a sense we use every time we eat, scientists are still trying to figure out exactly how it works. Chemicals from food hit tiny nubs on our tongue called papillae that hold taste buds. There, the chemicals fit like a key into receptors molecules that are like locks. When the receptors bind to a taste chemical, they activate the cell to which they are attached, sending a signal onward to the brain. Contrary to popular belief, scientists say that the process of tasting or enjoying food depends on our genes. It is said that our knowledge about this helps us to understand how our senses perceive taste and react to it.
Take a sip of lemonade and you taste an explosion of flavor. The sweetness of the sugar and the sourness of the lemons burst on your tongue. But the tongue doesn’t taste all by itself. It needs the brain to take chemical signals from food and turn them into what we sense as sweet and sour. Scientists are still unclear and didn’t quite understand how taste got mapped in the brain. If you are obsessed with the taste of lemons and can't stand sprouts, it means that you are a 'super tester' with 25% of the population. It also means that your tongue has the ability to recognize twice as many flavors as other people and that is why you are particularly sensitive to bitter tastes. Every taste is a constellation of brain cells, winking on in different patterns as an animal experiences a flavor.
Scientists have now discovered the existence of a 'thermal tester'. These are people whose ability to recognize taste in the tongue reacts to the heat of food. For example, ice cubes will look salty on the tongue while something hot will be sweet. People with a different type of gene are very sensitive to the smell and taste of coriander. The green coriander found in broths and salads gives them a taste of soap. It is a scientific fact that we use all our senses to eat or taste our food. Many parts of our tongue become active at the same time for how salty, bitter or sweet something is, while simultaneously its sense of nose indicates the smell of an object and the touch of a hand with it indicates how smooth, hard, soft, or creamy an object is and all these together form a taste. According to Charles Spence, a professor of experimental psychology, smell plays an important role in taste.
The role of the brain in food preferences and dislikes has been acknowledged by many chefs. They are of the view that the strong smell adds to the flavor and as such many big companies and restaurants are benefiting from it. The element that recognizes taste carries the taste and smell of food to the part of the brain located in the middle of the forehead so that the brain can decide to respond. Professor Spence at a recent conference of the Royal Society of Medicine said that color, brightness and atmosphere all influence our senses and mood and accordingly determine the taste of food. Counting the experiences, the red color of food enhances the feeling of sweetness of things. However, if the plate in which the food is placed has the same color as that of food, it has a different effect on the taste. It is also experienced that if it has music there while eating food, it also enhances the taste of food, even the crispness of the chewing makes it feel fresh, and the food companies take care of it as much as possible. Thus by knowing how our senses of taste work can be very useful for public health, according to a research the problem of using too much salt in our diet can be solved through future science of food, as it is possible to add an element to the diet that makes you feel salty but actually reduces the amount of salt in the diet. Research on the supernatant gene can also show why children are so stubborn about eating that they will eat one type of food and reject the other. Children are more sensitive to bitt erness and have different tastes than adults.
To conclude with it different findings reveal that touch, sight and hearing have what’s called a spatial or topographical map in the brain. If you touch a dog with your fingers, the feeling will go to one spot in the brain that processes the touch from those fingers. If you brush the dog with your arm, that will go to a spot in the brain nearby. Each area of the brain that processes touch is laid out in a predictable pattern. For touch, the hip is next to the thigh, then the knee, then the shin and then the foot. It is like a map, going from one plaace to another and likewise sight and hearing also have predictable maps. But smell is different. All the inputs from our nose go to the brain’s olfactory cortex (olfactory refers to smell) the area which is not organized at all. Instead of a map from one smell to another, it’s a scattered spray of brain-cell islands. This means that taste is probably organized in the brain more like smell than like touch. Taste patterns in the brain look like tiny islands in a vast sea or, as they fire in response to a taste, like winking stars in a dark brain sky. When a flavor hits the tongue, it activates a taste cell for sweet, salty, bitter, sour or umami (savory). That taste cell then passes the delicious message on to a brain cell so your brain knows whether the mouth tastes a cake or steak. The cells in your taste buds make direct contact with everything that ends up in your mouth where tongue is a constantly changing the landscape. The surface of tongue is covered with taste buds, and each bud is filled with a mix of different types of taste receptor cells. The base of each taste cell in the bud is linked to a long tail called an axon. That axon is part of a brain cell, or neuron, located in a bundle of cells just behind your ear. This cell bundle takes the information from each taste-receptor cell and passes it along. This allows our brains to taste the difference between apples and oranges.
Dr. Ashaq Hussain is Assistant Professor Chemistry (Selection Grade)
At Govt. Degree College Chatroo Jammu and Kashmir and can be reached at [email protected]