Taste method. physiological bases of the gustatory method. flavoring substances

Taking food, a person not only satisfies hunger, but also receives sense gratification. The perception of taste is a complex concept that depends on completely unexpected factors. Professor Oxford University Charles Spence even created a special science that studies multisensory effects on the brain when eating food - gastrophysics.

A person's perception of a dish is influenced not only by taste, but also by color and smell. To improve them, there are many flavors, flavor enhancers, dyes. And this is not necessarily chemistry, on the contrary - modern cuisine strives for natural additives.

The palette of sensations

Tongue receptors are capable of recognizing salty, sweet, sour, bitter, pungent, astringent, tart, and pungent tastes. Also, during a meal, aroma molecules released by foods trigger a reaction in the olfactory centers. Both signals enter the brain almost simultaneously, and the neurons decode them. This is how the sensation of taste is formed. And that is why with a runny nose, when there is no sense of smell, it seems that the food is bland.

A number of factors help to add vivid impressions to a simple meal:

• The temperature of the food significantly alters the intensity of all flavors except sweet. Warm or hot drinks enhance the experience of food, while cold drinks not only make it bland, but also make you eat more.
• Flavors add variety to your food. In addition, they often have pleasant "side" effects. For example: Peppers and mustard help improve digestion.
• Tactile sensations can both bring additional pleasure and completely discourage the desire to try the product. Many do not tolerate slimy dishes, and the legs of insects, so beloved in Asia, will cause a gag reflex in Europeans.

Aroma takes a special place in the formation of taste. V recent times open kitchen in restaurants has become fashionable, where visitors not only see the cooking process, but also feel all the smells before their order is brought to them. Scientists have found that aromas can affect well-being. Fennel and dill will improve your appetite, while vanilla will cheer you up by relieving anger and anxiety.

His Majesty the Color

Nutritionists know a special technique that helps to normalize digestion - color therapy. However, nature has been using it for a long time: most ripe fruits are red, orange, yellow. How brighter than paint, the "tastier" the dish. However, the contrast of food with the color of the dishes should not be allowed, otherwise the effect will be the opposite. A light blue, purple, blue or black plate can ruin your appetite. This is why restaurants usually use neutral white dishes.

Although green is considered a symbol of health, children are wary of it. It is difficult to get a child to eat healthy greens: leafy vegetables, herbs, onions, cabbage. Kids love the variety of palettes, and manufacturers use this. To attract little customers, they try to add dyes of different colors to baby products. Bright dragees, cheerful flakes, colorful yoghurts - a riot of colors attracts kids. Parents, too, will not hurt to use this technique so that the child eats a healthy product.

Gastrophysics in action

Dietitians around the world are conducting hundreds of studies with unexpected results. Marketers use these discoveries to promote products. Their methods are sometimes surprising, but, oddly enough, they are effective.

• Music not only pleases the ear, but also affects the taste: the piano will make the fruit "sweeter", and low heavy sounds will add bitterness.
• Correctly selected lighting creates an aura that best suits the meal: soft light - romantic wines with light snacks, bright neon - cocktails and snacks.
• Employees of the London Museum of Natural Sciences conducted an experiment that fully confirmed: the food should be aesthetically pleasing on the plate. Therefore, presentation is a special part of serving food in a restaurant.

Food keeps you alive, and tasty food also cheers you up. For thousands of years, chefs have tried to invent new additives and cooking methods that make simple food a real treat. No wonder that gourmets eat only what they like, because dopamines and endorphins - hormones of joy and happiness - provide a positive attitude, making a person more confident and successful.

The simplest joy in human life is delicious food. It would seem that you go to the kitchen, open the refrigerator, spend some time at the stove - and voila! - aromatic dish already on the table, and endorphins in the head. However, from the point of view of science, all food intake from and to develops into a complex multifaceted process. And how difficult it is sometimes for us to explain our food cravings!

The study of taste buds is engaged in a young and still developing science - the physiology of taste. Let us examine some of the basic tenets of the teaching that will help to better understand our taste preferences and momentary weaknesses.

Human taste buds

Taste is one of the five senses of perception, which are very important for human life. The primary role of taste is to select and evaluate food and drink. In this he is largely helped by other senses, especially the sense of smell.

The taste mechanism is driven by chemicals found in food and beverages. Chemical particles collecting in the mouth turn into nerve impulses that are transmitted along the nerves to the brain, where they are decoded. The surface of the human tongue is covered with taste buds, of which an adult has from 5 to 10 thousand. With age, their number decreases, which can cause certain problems with distinguishing between tastes. The papillae, in turn, contain taste buds, which have a certain set of receptors, thanks to which we experience the whole gamut of taste variety.

They only respond to 4 basic tastes - sweet, bitter, salty and sour. However, today the fifth is also often distinguished - umami. The homeland of the newcomer is Japan, and in translation from the local language it means "mouth-watering taste". In fact, umami is the taste of protein substances. The sensation of minds is created by monosodium glutamate and other amino acids. Umami is an important flavor component of Roquefort and Parmesan cheeses, soy sauce, and other non-fermented foods such as walnuts, tomatoes, broccoli, mushrooms, and heat-treated meat.

A completely natural explanation for the choice of food is considered to be the socio-economic conditions in which a person lives, as well as the work of his digestive system. Meanwhile, scientists are more and more inclined to the option that taste preferences are determined by genes and heredity. For the first time this question was raised in 1931 during research, during which there was a synthesis of the odorous molecule phenylthiocarbomide (FTC). Two scientists perceived the substance differently: for one it was bitter and very odorous, while the other found it completely neutral and tasteless. Later, the head of the research group, Arthur Fox, checked the FTC on members of his family, who also did not feel it.

Thus, recently, scientists tend to think that some people perceive the same taste differently and that some are programmed to gain weight from french fries, while others can eat it without harm to their figure - this is a question of heredity. In support of this statement, scientists from Duke University in the United States, together with colleagues from Norway, have proved that people have different composition genes responsible for smells. The study focused on the relationship of the OR7D4 RT gene to a steroid called androstenone, which is abundant in pork. So, people with the same copies of this gene are disgusted with the smell of this steroid, and the owners of two different copies of the genes (OR7D4 RT and OR7D4 WM), on the contrary, do not feel any dislike.

Interesting facts about tastes

• Taste papillae in the human language live on average 7-10 days, then die and new ones appear. So don't be surprised if the same taste seems a little different to you from time to time.

• About 15-25% of people in the world can be safely called "super-tasters", that is, they have an extremely sensitive taste, since there are more papillae on the tongue, and therefore, more taste buds.

• Taste buds on the human tongue for sweet and bitter tastes were only discovered 10 years ago.

• All pure tastes are felt by a person in exactly the same way. This means that we cannot talk about several types of sweet taste. To taste, there is just one sweet taste, which, however, can vary in intensity: be brighter, richer or faded. The situation is similar with other flavors.

• Taste buds are most sensitive in the range of 20-38 degrees. If you cool the tongue, for example, with ice, then the taste of sweet food may no longer be felt, or it may change significantly.

• Good taste is formed in the womb. So, scientists have found that the taste of some products is transmitted not only through mother's milk, but also through the amniotic fluid while the baby is in the mother's stomach.

• American scientists conducted a study that found the dependence of taste preferences on the age and gender of a person. So, the majority of girls prefer sweets, fruits, vegetables. Boys, on the other hand, love fish, meat, poultry and are mostly indifferent to chocolate.

• During a flight due to high level noise in humans decreases taste sensitivity to salty and sweet.

• Cookies taste 11 times better when washed down with milk drinks. But coffee, on the contrary, "kills" all other sensations. Therefore, if you want to fully enjoy your dessert, it is better to choose the right drinks and consume coffee separately from other food.

Sweet

The sweet taste is perhaps the most pleasant for the majority of the world's population. No wonder the expression "sweet life" appeared, and not some other. At the same time, not only flour and confectionery products are sweet, but also products of natural origin. Together with this, they are also useful. Most sugary foods contain a large number of glucose. And as you know, glucose is the main metabolic fuel for the human body. That is why the taste buds easily recognize the sweet taste, and also simultaneously produce the hormones of happiness - serotonin and endorphin.It should be noted that these hormones are addictive. This is the explanation for the fact that we prefer to seize depression and stress with something sweet.

It is no secret that excessive consumption of sweets adversely affects the shape and condition of the skin. However, do not give up desserts altogether. Do not eat treats on an empty stomach and, whenever possible, try to replace them with dried fruits, honey, nuts.

Sour

The majority acidic foods includes ascorbic acid. And if you suddenly craved something sour, you should know that this may indicate a lack of vitamin C in your body. Such swings in taste may even signal an impending cold. The main thing is not to overdo it: you should not actively supply your body with this useful substance, everything is fine in moderation. An excess of acid negatively affects the functioning of the digestive system and the condition of the enamel of the teeth.

If a lot of acid is involved in the metabolism, the body will try to get rid of its excess itself. This happens in a variety of ways. For example, through the lungs by exhaling carbon dioxide or through the skin through sweating. But when all the possibilities are exhausted, acids accumulate in the connective tissue, which impairs the functioning of the digestive system and provokes the accumulation of toxins in the body.

The daily intake of vitamin C for adult men and women is 70-100 milligrams. It is especially abundant in sour berries (gooseberries, currants, cranberries), citrus and kiwi fruits, and fresh vegetables (especially bell peppers).

Pathways and centers of taste. The so-called string drum and glossopharyngeal nerve, the nuclei of which are located in the medulla oblongata, serve as conductors for all types of gustatory sensitivity. Many of the fibers are specific because they only respond to salt, acid, quinine, or sugar. The most convincing hypothesis is that the four basic taste sensations - bitter, sweet, sour and salty - are encoded not by impulses in single fibers, but by the distribution of the frequency of discharges in a large group of fibers, which are differently excited by the flavoring agent.

Afferent signals caused by gustatory stimulation enter the nucleus of a solitary bundle of the brainstem. From this nucleus, the axons of the second neurons ascend as part of the medial loop to the thalamus, where the third neurons are located, the axons of which are directed to the cortical center of taste.

7.2. Taste and perception

For different people, the absolute thresholds of taste sensitivity differ significantly, up to "taste blindness" to individual agents. The absolute thresholds for gustatory sensitivity are highly dependent on the state of the body, changing, for example, during fasting and pregnancy. The absolute threshold of taste sensitivity is assessed by the occurrence of an indeterminate taste sensation, which differs from the taste of distilled water. Differential thresholds of gustatory discrimination are minimal at medium concentrations of substances, but with a transition to high concentrations they increase sharply. So, a 20% sugar solution is perceived as the sweetest possible, a 10% sodium chloride solution as the most salty, a 0.2% hydrochloric acid solution as the most acidic, and a 0.1% quinine sulfate solution as as bitter as possible. Threshold contrast (dI /I) for different substances varies considerably.

Taste adaptation. With prolonged action of the flavoring agent, adaptation to it develops, which is proportional to the concentration of the solution. Adaptation to sweet and salty develops faster than to bitter and sour. Cross-adaptation was also found, i.e. change in sensitivity to one substance under the action of another. Sequential application of several gustatory stimuli produces gustatory contrast effects. For example, adaptation to bitter increases sensitivity to sour and salty, while adaptation to sweet sharpens the perception of all other taste sensations. When several flavors are mixed, a new taste arises that is different from the taste of the components that make up the mixture.

Olfactory and gustatory senses

Perception of smells. Smell is an extremely subtle sense. A person can easily distinguish and memorize up to 1000 odors, and an experienced specialist is able to distinguish 10,000 - 17,000 odors. Along with the concept of smell, the terms "aroma" are used to denote a pleasant smell and "bouquet" to characterize a complex aroma "that develops as a result of enzymatic and chemical processes, for example, when aging wines and cognacs, when ripening rennet cheeses, canned fish types "Sprats" and "Sardines", when fermenting tea, roasting coffee beans, etc.

The olfactory organ is located in the nasal cavity. The olfactory epithelium is located on an area of ​​3 - 5 cm 2, has yellow due to the presence of dye grains in special sensitive cells located in the mucous membrane of the upper part of the septum, nasal vault and other parts of it. The olfactory epithelium, located in the upper part of the nasal cavity, is in direct communication with the oral cavity. Molecules of volatile aromatic substances in the oral cavity easily enter the nasal cavity through the nasopharynx.

A variety of smell occurs when the trigeminal nerve is excited, which has many endings in the nasal cavity. The nerves of the pharynx and tongue, the vagus nerve of the larynx and other nerves are poorly excited when exposed to aromatic substances.

The stimulating effect of certain odors on the ability to intensive physical or mental work, as well as the calming effect of certain odors on the nervous and other systems of a person was found.

Over the past 100 years, about 30 different odor hypotheses have been identified, but there is still no scientifically proven theory. The stereo-chemical and membrane hypotheses are more widely known. The latter explains the occurrence of odor by the permeability of the cell membrane to molecules of a volatile substance, but does not substantiate a wide range of perceived olfactory sensations. According to the stereochemical hypothesis, odor recognition depends on the correspondence of the size and shape of the molecules of the aromatic substance to the so-called particle geometry) to certain holes (pores) in the olfactory region of the nose. P. Martin (England) received the Nobel Prize for the hypothesis on the mechanism of the sense of smell. It is based on the interaction of enzymes activated by the molecules of the odoriferous substance with the corresponding coenzymes.

Along with unresolved difficulties in the theoretical interpretation of the mechanism of smell perception by the olfactory organ, there remains unsolved problem classification of odors. Several classification systems have been proposed, dividing odors into, 7, 9, 10, 11 groups, which, in combination, create existing shades. For example, the classification created by Crocker and Tsnderson (1927) divides all known odors into four groups:

Aromatic-floral (some ketones with a violet scent, as well as a musk scent);

· Acidic (elements of this smell are contained in formic and acetic acids);

· Burning smell (roasted coffee and furfural);

· Caprylic (goat, found in fusel oils, rancid fats, kerosene, gasoline, in the smell of decomposing corpses and animal secretions).

Most widespread received developed by Cupid in 1962 ᴦ. a classification that distinguishes seven basic, or primary, odors:

· Camphor (hexachloroethane);

Musky (musk, xylene);

Floral (a-amylpyridine);

Mint (menthol);

· Ether (ethyl ether);

Spicy (formic acid);

Putrid (hydrogen sulfide).

Ways to restore olfactory sensitivity

A glass of water is poured into an enamel pot, 2 drops of peppermint essential oil and a teaspoon of cologne are added to it, and then heated to a boil and breathing over steam for 3 - 5 minutes, making forced long breaths throughout the procedure. The course of treatment is 6 - 8 procedures daily or every other day.

Pour a glass of water into an enamel pot, bring it to a boil and add 10-12 drops lemon juice and 1 drop of lavender or peppermint essential oil. Breathe over the steam for 3 - 5 minutes each nostril, making forced breaths. The course of treatment is 10 procedures daily or every other day.

A coin in denominations of 1 or 2 rubles. smeared with honey, applied to the very middle of the back of the nose and fixed with a plaster. Better yet, use an old copper coin. You need to hold the coin for at least 30 minutes daily. Often, after 15 - 20 procedures, the sense of smell is fully restored.

Add 10 drops of lemon juice and cologne to a glass of water heated to 50 "C. Gauze or cotton cloth is soaked in this water and applied to the entire surface of the nose for 5 - 7 minutes. The course of treatment is 10 procedures daily.

Vietnamese balm "Golden Star" is left in the sun for several hours in a closed jar, then rubbed into the bridge of the nose and in the middle of the forehead. The course of treatment is 7-10 procedures daily.

It is helpful to learn to tense and relax your nose muscles. This exercise restores the sense of smell well. You need to keep the muscles tense or relaxed for at least a minute. It is extremely important to do the exercise every day for 10 minutes.

Warming up with a blue lamp has a positive effect on hyposmia. You can also use a conventional 40 W bulb. Put on your sunglasses, remove the lampshade from the table lamp, tilt your head back so that the light falls into the nasal cavity. The distance from the lamp to the nasal cavity should be no more than 25 cm. Carry out the procedure for 10 - 15 minutes daily or every other day for a week.

The well-known procedure according to the yoga system - drawing in warm salted water by the nose - also helps to improve the sense of smell. Add salt to a glass of warm boiled water at the tip of a knife. Closing one nostril with a finger, slowly draw in water from the open nostril until it is in the throat. Then the water is spit out. Do the same with the other nostril. You can release water not through the mouth, but through the nose. It is advisable to use all the water poured. The course of treatment is at least 10 procedures.

The described procedures can be varied as desired. Despite their simplicity, they are great at helping to improve the sense of smell.

Taste sensations... Smell perception is inextricably linked to the sense of taste. In analytical terminology, there are four basic types of taste:

salty- a sensation for which sodium chloride solution is a typical taste stimulus;

sweet- a sensation for which a typical taste stimulus is an aqueous solution of sucrose;

bitter- a sensation for which typical taste stimuli are aqueous solutions of caffeine, quinine and some other alkaloids;

sour- a sensation for which typical taste stimuli are aqueous solutions of tartaric, citric and a number of other acids.

Other types and shades of tastes are complex sensations of these tastes. The term “stimulus” is recommended to denote a substance or electrophysical effect that causes a gustatory sensation when interacting with chemoreceptors.

Recently, alkaline and astringent have been added to the four types of flavors. Alkaline occurs from chemical irritation of the oral mucosa and is not caused by specific taste buds. A typical stimulus for the alkaline taste is an aqueous solution of sodium bicarbonate, and for an astringent taste, an aqueous solution of tannins.

Taste sensations are perceived with different speed... The most rapidly arising sensation of salty taste, then sweet, sour, much slower - bitter. This is due to the uneven distribution of taste buds.

The outer perceiving part of the human taste organ is represented by taste buds, which are located in the so-called papillae (kidneys) of the tongue. Individual bulbs are also scattered in the mucous membrane of the soft palate, the posterior wall of the epiglottis, and even on the lateral walls of the larynx. The total number of taste buds can reach several thousand.

Taste receptors are susceptible to rapid death and neoplasm. With age, the number of taste buds can decrease by two to three times, which leads to a strong decrease in taste.

Taste receptors on the tongue have a pronounced specificity. At the very tip of the tongue and along the edges there are large mushroom papillae, each of which has 8-10 bulbs. The sweet taste is most felt at the end of the tongue, salty at the edges of the front of the tongue, and sour at the edges of the back of the tongue. At the base of the tongue are grooved papillae, each of which has 100 - 150 taste buds that perceive a bitter taste.

The organ of taste (tongue) of a person is a chemical analyzer. The mechanism of its functioning is that the substance, dissolved in water or in saliva, penetrates through the gustatory pores to the bulbs, in which chemical irritations are converted into nerve impulses that are transmitted along nerve fibers to the central nervous system.

The chemical receptor on the tongue is protein. Immersion of the tongue in the solution is usually not sufficient to induce a taste sensation. In this case, there is a sensation of touch, sometimes cold. Taste perception occurs better when the tongue touches the walls of the vessel, and living the tongue against the palate facilitates the penetration of the sample solution into the pores of the taste buds of the bulbs

There is no generally accepted theory of taste, since the mechanism of functioning of the cells of the taste organ is not well understood. The existing hypotheses are based on physicochemical, chemical and enzymatic prerequisites. A certain relationship has been established between the chemical nature of the flavoring agent and the sensation of taste it causes. But substances of different structures can have the same taste and, on the contrary, substances of the same chemical. natures have different tastes. Not only sugars are felt sweet, but also many amino acids, saccharin. The protein tuamatin, which has a molecular weight of 22 thousand, consists of 207 amino acid residues and is 8 thousand times sweeter than sucrose, has been isolated from plant raw materials.

With the exception of sodium chloride, which has a purely salty taste, all other salts have a more or less mixed taste. The quality of the salty taste is mainly determined by the anion, and the intensity of the taste is determined by the cation. At a sodium chloride concentration (mol / l) of 0.009, the solution has no taste, in the range of 0.01 - 0.03, the solutions have a sweet taste of varying intensity, 0.04 and above - salty. At a concentration of potassium chloride (mol / l) 0.009 - 0.02, solutions have a sweet taste, 0.03 - 0.04 - bitter, 0.05 - 0.1 - bitter and salty, and starting from 0.2 and higher - salty, bitter and sour. Potassium iodide has a bitter taste, potassium bromide is salty-bitter, calcium chloride is bitter.

The intensity of the organoleptic sensation of table salt in fish is 0.4 - 1% lower than in a solution of the corresponding concentration.

Sour taste is caused by inorganic acids, as well as organic acids and their salts. Sour taste depends mainly on the concentration of hydrogen ions. For organic acids the intensity of the sour taste sensation exceeds that expected with the corresponding concentration of hydrogen ions.

Typical bitter substances are the alkaloids quinine and caffeine. Many mineral salts, most of nitro compounds, some amino acids, peptides, phenolic components of smoke and smoked meats have a bitter taste.

Threshold concentrations of compounds in aqueous solutions and products do not coincide, and this must be taken into account in technological workings. Some substances can mask or, conversely, enhance the taste of other food components. Mixing base flavors, as well as changing their intensity, can cause such complex complex phenomena as rivalry of tastes, compensation of tastes, disappearance of repeated tastes, contrasting tastes, and other sensory sensations.

Influence of factors on taste and smell.Adaptation is the adaptability of the organs of taste and smell, which consists in a decrease in their sensitivity caused by prolonged exposure to a stimulus (continuous or repetitive) of the same quality and constant intensity. When the stimulus stops acting, then there is a restoration of gustatory and olfactory sensitivity. In contrast to sight, the organs of smell and taste are subject to rapid adaptation. The adaptation to odors in humans is more pronounced than To tastes. In particular, a person usually does not smell his clothes, his home, his own body.

G.A. Wux gives information about the development of adaptation of the organ of smell to odors. So, the time, which is extremely important for adaptation to the smell of certain substances, will be as follows (min): iodine solution - 4, garlic - 45 or more, camphor - 2 or more, phenol - 9 or more, coumarin - 1 - 2, essential oils- 2 - 9.2, cologne - 7 - 12.

In some cases, with repeated exposure to very weak stimuli arriving sequentially one after the other v significant periods of time, the sensibility of the organ of taste or smell can increase and persist for a long time. This phenomenon is usually called sensitization.

Increasing sensitivity is achieved with the help of stimuli, the intensity of which is equal to the threshold, as well as due to the activity of the taster himself. The interval between repeated stimulus exposure depends on the type of stimulus and the sensory abilities of the tasters. For example, for hearing and vision, this interval should be 3 minutes for one taster and 1.5 minutes for another. Sensitization is characterized by the persistence of maintaining this property.

G.A. Vuks notes that experimentally induced sensitization of smell can be retained for 7 - 22 days and then recover from a few workouts. To increase the sensitivity to a certain stimulus by an average of 60 - 70%, you need to feel its effect on the corresponding sensory analyzer for 30 - 35 minutes with an interval of 1 - 2 minutes.

sensitization in relation to the code smell entails a slight increase in sensitivity to other odors.

Sensitization to red tends to reduce sensitivity to green, and in some cases to yellow. Sensitization to green color results in decreased sensitivity to red, ᴛ.ᴇ. along with the selectivity of the obbl, it is possible to simultaneously change the thresholds of other colors. This phenomenon is typical of taste: sensitization of one of the basic tastes affects other basic tastes. However, these patterns have not been fully studied. For example, sensitization to bitter has been found to simultaneously increase sensitivity to sweet taste, and sensitization to sweet taste improves sensitivity to bitter taste. Salty sensitization can decrease sensitivity to sweets in some tasters and increase it in others.

According to the profile of the taster, one can observe increased sensitivity to certain chemicals... There are cases when a laboratory assistant performing a chemical analysis of the mass fraction of table salt in a food product, over time, could sensibly accurately determine the salinity of the product. Similar cases are known in the alcoholic beverage industry, when the taster, thanks to the sensitization of the taste and smell analyzers, determines the alcohol content in beverages with high accuracy. In the perfume industry, tasters are selectively sensitive To certain smells.

Individual susceptibility to odors and tastes. Some people have a lack of smell in relation to either all odorous substances, or to one substance, or to a group of substances. This phenomenon is usually called anosmia and was found relative to butyric acid, trimethylamine, hydrocyanic acid, skatole alcohol and a number of other substances.

Anosmia is more common in men (about 20%), less often in women (about 5%). It is believed to be inherited by descendants of the same sex. Anosmia maintains a normal sense of smell for many common odors. In most cases, a person does not realize that he has a partial lack of smell. Extremely great importance this phenomenon has in the selection of specialists in sensory analysis.

Loss of smell must be due to injury from illness, traffic accidents, or medication. Diseases of the nasopharynx often lead to a decrease in the function of smell: chronic rhinitis and chronic inflammatory diseases paranasal sinuses - sinusitis, frontal sinusitis, sphenoiditis, rhinovirus infections. The sense of smell can be reduced due to adenoids, polyps in the nose, curvature of the nasal septum.

Cases of decreased olfactory sensitivity to all or individual odorous substances are not uncommon. This phenomenon is usually called hyposmia. Much less often there is an unusually high human olfactory sensitivity either to all odorous substances, or to one substance, or To group of substances. This phenomenon is usually called hyperosmia.

Hallucinations of the sense of smell are also possible, manifested in the fact that a person senses a smell, which in reality does not exist. This type of damage to the sense of smell is usually called spontaneous sense of smell or by parosmia.

Lack of gustatory sensitivity to either all flavors, or To to one substance, or to a group of substances, it is customary to call ageusia. Reduced gustatory sensitivity to all or individual substances is usually called hypogeusia, and an unusually high sensitivity - hypergeusia. The perverse ability to feel a taste that is not characteristic of a given substance or group of substances is denoted by the term parageusia.

Scientists believe that the behavior of the taster can be predicted based on the type of physique. It is noted that tasters with a thin and fragile body structure (leptosomics) have twice as many taste aversions as full and squat tasters (picnics).

The results of studies on the influence of gender, age and pH of saliva on the taste sensitivity levels of the taster are ambiguous. It was found that the pH values ​​of saliva correlate with the taster's susceptibility to bitter solutions and bitter taste of food products. After tasting, the acidic reaction of saliva, as a rule, decreases, and its alkalinity increases.

Several studies have compared the levels of taste sensitivity with the social status and cultural level of the tasters tested. Thus, in groups with low characteristics of status and culture, high thresholds for recognition of basic tastes were observed. The Japanese are considered the most subtle in terms of taste perception. It was found that genetic taste analyzer disorders are more common among Europeans and only 6-10% of such disorders are observed in African blacks.

Individual differences the thresholds of sensitivity in humans are significant: for the sense of smell 1000: 1, for the organ of taste 64: 1. A small (not exactly accounted for) part of the population is completely devoid of sensitivity to taste or smell.

Influence of age. WITH with age, the sensitivity to odors decreases in a logarithmic sequence. This extends not only to the sense of smell, but also to sight, hearing, taste and touch. It is believed that a person loses up to 50% of visual acuity and hearing by 13 - 15 years, the ability to perceive smell and taste - by 22 - 29, tactile sensitivity - by 60 years. The age factor is not decisive. Taking into account the dependence on natural data, lifestyle, nutrition, habits, nature of work, fitness of sensory organs with age, a person may increase the sensitivity of smell, taste, touch, much less often - hearing and vision.

Smell memory and representation - it is the ability of a person to recognize those smells with which he previously had to meet, ᴛ.ᴇ. memorize and recognize a known smell. Usually, a person is able to distinguish from several hundred to several thousand different smells. Qualified tasters must be able to recognize at least 10,000 odors. Experts develop their abilities through exercises and can distinguish up to 17 thousand varieties of smell. The ability to remember odors varies greatly among humans. Masking odors are cases of suppression of one odor by another. If two or three odors act on the olfactory organ at the same time, it may happen that none of them will show its real properties, and the perceived sense of smell will be vague or not perceived at all.

Compensation for odors and tastes. Compensation is characterized by an increase, decrease or disappearance of the sensation caused by the main taste or smell, and is associated with the presence of small amounts of a substance of a different taste or smell. Distinguish between positive and negative compensation. In the first case, the main taste or smell is enhanced by the influence of another taste or smell, in the second, the main sensation is weakened.

For example, fructose turns out to be sweeter in acidic environments, and glucose feels less sweet with increasing acidity. The palatability of sugar mixtures is not a simple summation of the sweetness intensities of the components. Typically, the sugar mixture is less sweet than the calculated sum of the ingredients.

With the simultaneous exposure to two different taste impulses, the feeling of a weaker one may disappear. Salty, sweet, sour tastes easily disappear.

When the smells of two chemically non-reacting substances are mixed with each other, a mutual weakening of these smells may appear, ᴛ.ᴇ. their mutual compensation. A large number of odorous substances have been found, the odors of which are mutually compensated.

It is not allowed to suppress defamatory odors and tastes in food products that characterize negative signs of quality (for example, when using stale raw materials, fats with signs of oxidation, components with defamatory odors, etc.).

Flavoring modifications. A tropical plant is known as a sweet taste inhibitor Gymnema sylvestre, ĸᴏᴛᴏᴩᴏᴇ grows in South India, Ceylon and the tropics of West Africa. Fruit of another tropical plant Miracle fruit modify the sour taste. For example, lemons acquire the taste of sweet and sour oranges. The flavor modification effect lasts for 30-60 minutes. Fruit properties Miracle fruit used in winemaking to soften the sour taste of wines, as well as in the bakery and confectionery industry.

Secondary, or residual, the taste appears after the product has been tasted lasts for a while and differs from the characteristic taste. Aftertaste usually reduces the consumer value of the product. The appearance of a long-lasting bitter secondary taste is characteristic of fat rancidity.

Flavoring contrast can be a source of error in sensory tests. For example, ordinary water, especially distilled water, seems sweetish if a salty taste is felt before tasting it. A sour taste seems more sour and even unpleasant if it is preceded by a sweet sensation. The phenomenon of taste contrast can distort the results of evaluations of aged wines if sweeter wines were tasted before them. For the same reason, you should not evaluate light-salted products after strong or medium-salted products. Taste contrast is extremely important to consider when determining the order of submission of samples for tasting.

Taste illusions. L. Bartoshchuk found that after tasting the artichoke, clear water feels sweet.

Concept taste harmony characterizes the desirability of sensations and is associated with the compatibility of different tastes. Sweet and sour, salty and sweet harmonize well, it is more difficult to get a harmony of bitter and sweet, it is almost impossible to combine bitter and salty, as well as bitter and sour tastes. Taste harmony develops during the maturation of wines and canned food. Knowledge of technology, organoleptic laws and experience with food products contribute to the creation of taste harmony.

Influence of color on taste. It is noted that red solutions are perceived to be sweeter than colorless sweet solutions of the same concentration. Yellow and light green colors increase the subjective acid rating. Experiments at the University of Tartu have shown that thirst quenching is achieved soft drinks best if they are light green. Complex associations often arise between color, taste and smell.

For example, dark green increases the intensity of taste and smell, yellow gives a denser smelling sensation, and red and light green makes odors easier to perceive. Blue colors different shades cause sensations of a bitter taste and unpleasant technical nuances in the smell. G.A. Vuks has compiled a semantic map, which can be used to describe the smell and taste of different food products. In particular, the taste raspberry jam described in terms of: warm, heavy, soft, etc.

The influence of external factors. The sensibility of smell and other sensory perception changes under the influence of external conditions... The degree of air purification, temperature, relative air humidity, room illumination are especially important; for example, in an odorless (deodorized) room, the sensitivity of the sense of smell increases by 25%. So, as the temperature rises, the intensity of the smell increases. The optimum temperature is 37 - 38 "C. A further increase in temperature does not increase the intensity of the odor, but, on the contrary, decreases it. Temperature fluctuations in the odorimetric laboratory cause significant errors in the results. High relative humidity favors better perception of odors. on general state central nervous system and indirectly on the sense of smell of a person.

Other factors also affect the taste and smell of tasters: for example, the shape food product͵ state of hunger and satiety, associations, personal motives and authorities.

Olfactory and gustatory sensations - concept and types. Classification and features of the category "Olfactory and taste sensations" 2017, 2018.

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TASTING MECHANISM

During tasting, a number of physiological stimulants of the senses are used, which are the components of wine that cause taste and smell. The terminology of this process requires some clarification.
A stimulus, or pathogen, is a physical or chemical agent that causes stimulation, excitement, and response of specific sensory receptors.
Sensation is a subjective phenomenon, a reflex resulting from stimulation of the organoleptic apparatus.
Perception is sensory awareness, the interpretation of sensations, it is the experience acquired by the taster that allows him to interpret sensations. This implies the need for special training of the taster, so that he always keeps in mind big number memories of various sensory sensations. This is the reason why the pungent sensation of taste by experienced tasters seems to be indispensable in winemaking today. More detailed coverage of the issue of sensations is given in the works (Magnan, 1965; Wedel et al, 1972).
Other definitions of interest to the taster are sensation and identification thresholds. The threshold of sensation, or detection, is the smallest value of a stimulus that arouses a sensation. It corresponds to the minimum amount of sensation-producing product, although it may not be identified. For example, 18% of people sense 0.5 g of sucrose per 1 L of water, but they can accurately identify it only at a concentration of 1 to 2 g per 1 L of water.
The identification threshold, or recognition, exactly corresponds to the minimum amount of recognized and identified product.
These thresholds depend on the severity of the taste sensations of people, this is precisely what is one of the important qualities when selecting tasters.
Wine tasting is an expression of the sum of sensations perceived simultaneously or sequentially. When wine is consumed without sufficient attention, these sensations merge into one whole. Analytical tasting aims to separate, arrange, and finally identify different sensations.

Many of our senses participate in the tasting, the perceived sensations come from various types of stimulation of our sensory perceptions: visual, olfactory, gustatory, to which tactile (tactile) and thermal receptors of the oral cavity must also be added, as well as general chemical susceptibility that causes sensations of irritation character or, as an extreme case, pain.
When they taste wine, take it by mouth, it must be borne in mind that the perceived sensations come not only from the organ of taste, but also from the organ of smell. The nose participates in the creation of these sensations even more than the tongue, and therefore, under the word "taste" of a substance, it is customary to understand the sensation that is actually perceived, first of all, by the sense of smell. During tasting, the warmth of the mouth, the movement of the cheeks, tongue, the slight inhalation of air that some tasters produce, even their normal breathing, send volatile substances into the nose, which make up the aroma and bouquet of the wine. Swallowing movement that is difficult not to do when tasting, causing
slight compression of the oral cavity, in the same way, sends vapors of the substance into the nasopharynx and contributes to the perception of odor. Part of the nasal cavity still perceives the sensation of wine when, after tasting, the liquid is exhaled from the mouth or swallowed and the liquid is exhaled through the nose. At this moment and during many subsequent exhalations, they perceive a smell that has permeated the mucous membranes of the mouth.
During the tasting, it is not difficult to get rid of the olfactory sensations so that only taste sensations remain in the full sense of the word; if you pinch your nostrils while tasting, you have to wonder how poorly the taste is perceived; in these conditions, one cannot even say that one can taste the wine. This occurs with a cold.
Thus, in the complete absence of the sense of smell, perception disappears. Usually in such cases it is said that "the taste is lost", when in reality it is about the sense of smell.
As already mentioned, taste in the generally accepted sense of the word also includes the olfactory sensations perceived by the internal pathways, while taste as such is only that part of the taste sensation that is perceived by the tongue. The term "bouquet" is understood as a set of sensations perceived by the nose or mouth during the tasting.
Table 2.1 provides a list of the senses and sensations associated with tasting, which are grouped according to rational terminology.

Visual sensations

Sight is the first of the senses through which tasting is performed. The visual sensations give an idea of ​​the color (intensity, hue) and transparency (haze, shine) of the wine. But the appearance of the wine also speaks of other qualities: its fluidity, selection carbon dioxide, the influence of the phenomena of capillarity on the walls of the glass, depending on the percentage of alcohol. These are elementary data that prepare and in many ways facilitate the judgment of wine with the help of other senses. Cloudy wine often gets bad grade taste. The color indicates the age, state of the wine. It is very difficult to taste wine without seeing it and therefore it can be confused when blindly tasting dry white low-acid wine with rosé or red wine containing little tannin. Illumination can have an indirect effect even on the acuity of smell: with sufficient illumination, odors are perceived better.

Table 2.1
Sense organs associated with tasting

Organs	Sense organs and sensations caused by them	Perceived characteristics
	Vision- visual sensations	Color, transparency, fluidity, gas evolution	Appearance
	Smell (anterior nasal passages) - olfactory sensations		Smell
	Smell (posterior nasal passages) - olfactory sensation	Aroma in the mouth Taste	Taste
	Sense of taste Taste sensations	Taste in the true sense of the word
	Mucosal reaction Chemical sensitivity	Astringency, astringent taste, pungency Tingling
	Tactile sensations	consistency, fluidity, oiliness	Touch
	Thermal sensations	Temperature

Olfactory sensations

These sensations are of the greatest importance for the tasting. The olfactory organ is located in the upper part of the nose (Fig. 2.1). The nose itself is not
organ of smell in exact meaning of this word, it is just a channel for access of inhaled air to the olfactory mucosa. There are three shells in the nasal cavity, one above the other. The olfactory mucosa is located at the level of the middle shell on the other side of a narrow slit with an opening of 1–2 mm, called the olfactory slit.

Sensitive mucous membrane, thin and smooth, yellow pigmented. This macula is very small in size (approximately 2.5 cm 2). On its surface are thin lengthenings of neurons, or olfactory cilia, which are washed by mucous fluid.

Rice. 2.1.
1 - lower shell; 2 - middle shell; 5-top sink; 4 - the olfactory mucosa.

The shape of the olfactory organ makes it possible to understand that the mucous membrane is somewhat away from the path of the inhaled air, and, since access to it is possible only through a narrow gap, during normal breathing, only a small part of odor gases can enter it. The amount of odors entering this shell increases and thereby enhances the sensation, making successive breaths through the nose, "sniffing" the tasting drink and inhaling its smell through the nose.
Loss of smell caused by a runny nose is a consequence of the closure of the olfactory gap during tissue inflammation and tissue swelling.
The gustatory sensation is inevitably accompanied, although it is at first difficult to distinguish it, with an olfactory sensation. Most of our food products give off odor-rich vapors that enter the nasal cavity with the inhaled air and play a decisive role in creating the sense of taste. The smell is caused by contact of the sensory field with material particles that are in negligible quantities. This phenomenon is periodic, like breathing. It is felt during chewing movements with the mouth and manifests itself in in full by the end of swallowing, since the walls of the pharynx at this time represent a vast area for the evaporation of wine.
Human sense of smell is distinguished by exceptional subtlety. In terms of its sensitivity, it is much superior to chemical reagents. Smell is much more multifaceted and more sensitive than taste, and smell is much more complex than taste in the full sense of the word. If they can be reduced to just four elementary sensations of taste, then smells are the result of a significant number of elementary sensations. Of the many classification systems, odors can be reduced to nine main groups: animal, balsamic, forest, chemical, spice, empyreomatic, floral, fruit, vegetable. They are all present in the smells of wines, but wines best brands have a complex aroma or bouquet that is difficult to analyze. An experienced taster, upon careful examination, recognizes in them a mixture and sequence of pleasant smells, reminiscent of the smell of a flower, of a particular fruit, distinguishes oily, sour, aromatic and other tones in them. Most often, one or another aroma prevails in the bouquet of wine. But a mixture of many, mutually complementary odors forms a single whole, a new aroma, in which it is difficult to isolate its constituent elements.
When mixed, various odors are masked, mutually destroyed. For example, experiments show that the threshold for identifying an odorant by smell shifts dramatically when it is mixed with other odor-producing products.
The following observations regarding ethyl acetate, a substance that gives wines affected by acetic acidity, a specific character, are an example of olfactory interference. In an aqueous solution of ethyl acetate, its smell is easily captured even at concentrations from 25 to 30 mg / l. In a 10% alcohol solution, the threshold of sensation shifts, the smell is detected only at a concentration of 40 mg / l, therefore, its own smell ethyl alcohol masks other odors. This example shows why too high alcoholic content can reduce the bouquet of a wine. If any other ester is added to the ethyl acetate solution fatty acid(for example, ethyl enanthate, which, moreover, does not exist in wines), then only the content of 150 mg of ethyl acetate in 1 liter allows it to be identified. Finally, in wines, the smell of ethyl acetate appears only when its content reaches 180-200 mg per 1 liter. The more complex the mixture of odors and the more intense they are, the more the specific aroma of ethyl acetate is drowned out.
The harmonious fusion of normal wine aromas explains the impossibility of enhancing the bouquet with artificial smells. Such an attempt is illegal and condemnable. In addition, it does not end with success, since when artificial substances are added in small quantities, their smell drowns in the totality of wine smells without any result; if a certain threshold is exceeded, this smell becomes dominant and gives an artificial tone, which is immediately determined by a trained taster.
It has been shown above that, in tasting, the sense of smell is involved in creating the impression of taste. Such sensations are called gustatory and olfactory sensations. Of course, odorous substances are also involved in the formation of taste sensations, body sensations, oiliness. If the wine is deprived of all aromas by treating it, for example, with coal powder, it will immediately lose its body, although the fundamental equilibrium of the wine will hardly change.

Taste sensations

The receptor organs of taste are located in the papillae of the tongue. The cells that are sensitive to taste and are grouped into taste buds are very unevenly distributed on its surface. However, of the four types of papillae, only the grooved papillae, located on the back of the tongue, and mushroom papillae, which are located mainly at the tip and have papillae that are sensitive: to a specific taste, are involved in perception (Fig. 2.2). Nerve fibers that transmit signals to the brain excited: taste cells form three cranial nerves (lingo-pharyngeal, lingual, trigeminal). The center of perception-taste in the brain is located near the motor centers for chewing and swallowing. The perception of taste is closely related to these: functions.
It is assumed that there are only four elementary tastes perceptible to the tongue: sweet, sour, salty and bitter. All tastes that a person perceives necessarily fall into these four categories. One and the same substance can have only one taste, or it can present simultaneously, and sometimes sequentially, several elementary tastes.

Rice. 2.2. Distribution of mushroom, filamentous, layered and grooved papillae and perception papillae of four elementary tastes on the surface of the tongue:
1 - sweet 2 - salty; 3 - sour; 4 - bitter; 5 - grooved papillae; 6 - leafy papillae; 7 - threadlike; 8 - mushroom.

When a complex mixture is tasted, consisting of substances that have four elementary tastes, then it is perceived as one whole. Depending on the taste, the duration of the excitement from the wine can be different. The taste of sweet is felt immediately, bitter - it develops gradually: it grows and is perceived slowly, after the liquid is removed from the mouth. These facts are important to know because they explain the aftertaste experienced during tasting. The first impressions of taste received are very different from the last ones, and this difference must be carefully noted in time. The first taste impressions can give a sensation of sweetness, be pleasant, but then gradually give way to excessive bitterness, an unpleasant aftertaste.
Differences in the speed of perception are related, according to at least, partly with the fact that different tastes perceived in different parts language. The sweet taste is felt only with the tip of the tongue, sour - with the sides and part bottom surfaces tongue, salty - the edges, but by no means the middle of the tongue, bitter - only rear end tongue and only during swallowing. Most of the surface of the tongue is insensitive. On the other hand, it should be noted that in the mouth, taste in the proper sense of the word is perceived only through the tongue. Lips, cheeks, palate, which do not have taste buds, give only tactile or heat sensations.
There are four elementary flavors concentrated in wine, of which the main ones are sour and sweet. In addition, one cannot ignore the concentration of mineral salts in wine: the salty taste that they impart is clearly felt, although in wine it is masked by other aftertastes. However, there is no doubt that the mineral salts contained in wine give it a fresh flavor. On the other hand, a slight bitterness, accompanied by moderate astringency, - required quality good red wines. These flavors owe their origin to certain polyphenols. Other normal wine constituents may be slightly bitter (eg, butanediol-2,3). In addition, there may be wines in which bitter taste predominates as a result of defects or microbial diseases in the wine.

Persistence

Aftertaste refers to the final taste that persists for some time after the liquid has been swallowed or removed from the mouth. Feelings of this kind, lasting for a more or less long time, are usually called persistence or aftereffect. They can be of gustatory, olfactory or general chemical nature and are of great interest in terms of determining the class and quality of wine. Aftertaste is also called a final sensation that is different from the previous ones. It is usually bad.
Wedel and co-workers (1972) define the intense persistence of a scent: "Taken together, from which a sense of persistence is formed, careful observation of olfactory sensations shows that after a period of some equal intensity, it decreases sharply." Therefore, we agreed to designate the term "intense stability of aroma" this very first period. The taster can measure its duration in seconds. The unit of measurement is the codalia (from the French caudal - tail); it corresponds to 1 sec of toughness. The authors suggest using this unit of measurement when classifying highly distinguishable wines. They provide five classes corresponding to the following number of codalia: up to 3, from 4 to 6, from 7 to 9, from 10 to 12, more than 12. The method is tested and requires confirmation.

Other sensations

These sensations include chemical, tactile, heat, and less commonly - painful sensations... The listed sensations are perceived a large number corresponding receptors scattered throughout the mouth. The taste of a rather concentrated alcohol, pungent and scalding, relates more to the reaction of mucous membranes than to taste in the proper sense of the word. The same can be said for the tart or astringent taste of some polyphenols, which produces an unpleasant metallic taste. In fact, these impressions are transmitted to the brain by the wrong nerves that transmit sensations of taste in the proper sense, in addition, the tongue and cheeks are extremely sensitive organs of touch. They create impressions of temperature, consistency, volume, viscosity, oiliness.