(35) Everybody its own, fourth part (part 4).

As per the title this is the fourth part on taste exploration, a technological in-depth view of the sense. More is to come but we are nearing the end of this serie.

Judgement …

We have seen in the few preceding posts all the different senses that the human body possess except taste in the classic sense of the word. Taste is not flavour as discussed before and we will explore this concept in this and the next few posts where I will describe the notion of flavour as experienced through our bodies.

Recap

We realised before (please visit the website for more information), that all our senses are correlated and processed in our brain. It is a marvellous instrument.

Touch is everywhere our body is;

our vision is well located and with the eyes, both of them, you have depth;

sound comes through the ears;

smell goes through the nose;

food goes through the mouth and gives us taste.

Now that everything is in place, it is time to start processing food… as taste.

The tongue, physical + papillae

Indiscriminate

I have broken down the general idea of taste into different parts, and we will examine the body parts that are responsible for most of the perception of taste first: the tongue and its multiple resources.

There is one particular point that I would like to convey here, it is that the tongue will taste what is put to it, good or bad, it has no choice, this will be made only after contact.

The tongue is very soft and placed at the centre of the mouth. All food is processed by it and analysed. Texture and taste sensations are transmitted to the brain by different cells. These specialises in specific taste. Their location has for a long time been sought to be located by group of sensitivity to a special taste. What is known now is that the taste buds in general analyse diverse tastes, but not all. Some would be more responsive to some taste contrary to some others, and vice-versa. Bitterness and saltiness are detected from the last 2/3 part of the tongue.

It has been found out that some sort of receptor is more adept than others to analyse particular taste. These are called papillae and are divided in three kinds, and a fourth: the filiform papillae that do not have taste buds.

While most papillae are situated on the tongue , quite a few are to be found elsewhere within the mouth. Some are situated on the soft palate, and some others are all over the mouth really (pharynx, epiglottis, and at the entrance of the oesophagus as well). They combine with normal nerves to give a three-dimensional sense of texture coupled with taste. However, they are only a complement to the most numerous of the tongue, the prime sensory organ of taste.

Papillae are cells. They are connected by nerves to the brain which is very nearby. At the other end of the cell microvillus can be found. These are sensory transductions. Groups of papillae forms what is known as taste buds. Taste buds are numbering in average 4600 per tongue and more than 7000 for all over the mouth.

Some people have more taste buds and are able to taste more of the food, but do not usually appreciate green vegetables or fatty foods, they are the supertasters and represent more than 20% of the general population. In the same way children are more responsive to food and if they are described as picky eaters, it is only because of their ability to discern more acids and bitters.

Saliva, produced by the body, helps by its composition, mainly water, electrolytes and enzymes, the degradation of food into its components; in turn they will interact with the diverse taste buds for analysis. Saliva is as well very important for starch and fat digestion, and of course the good health of teeth and the mouth in general by pH control.

The taste buds are here to transmit the sensation of taste to the brain, they react to the food that we ingest. The initial chemical reaction provokes an important response from the cell through the nerve. The nerve transmission then decreases. Different aspect of the food can then be analysed and interpreted as taste layers.

The first reaction describes the stronger basic taste, and then the second and following reactions are concerned with the nuances and after effect of the food in the mouth. Intensity of the reaction is dependent upon the taste that it analyses, and detection thresholds are different upon the taste that is analysed.

Saltiness and sweetness have a high threshold, and then comes umami and closely behind sourness. However, bitterness has a very, very low threshold. It is normal due to the fact that this taste is associated with poisons.

Another important factor is thermal variations. Warmth brings sweeter sensations as opposed to coldness which is associated with bitterness and saltiness. It has to be noted as well that too cold or too hot and you do not really taste food but have a sensation of burning. Food at body temperature or slightly higher is well analysed by humans.

Three nerves bring taste communications to the brain. The facial nerve connects together the anterior two-thirds of the tongue to the brain; the hypoglossal nerve does the posterior tongue; the glossopharyngeal nerve connects the throats and palate areas to the brain. The trigeminal nerve is concerned with touch, temperature, and pain. They all combine together in the brain stem, which is primary concerned with awakening, stimulation, and identity.

The nerves messages are then assimilated within the brain proper with the impulses of the olfactory nerve to create a sensation of flavour. This is then interpreted in the temporal lobe and the cingulated gyrus dealing with emotions.

Lastly, all the above nerve transmissions combine in the frontal lobe of the brain, right above the eyes. There the experience is evaluated and categorised.

Intranet

We can distinguish five basic tastes from the mouth and fat. These are: sour, acid, salty, sweet; with the addition of savouriness, umami in Japanese.

Umami was discovered in 1909 at the Imperial University of Tokyo by Kikunae Ikeda, this taste is concerned with amino acids and rich protein food, and it translates as “delicious taste”.

Sweet taste is well known and liked as the body needs energy and finds it in abundance in sweet food.

Acidity is easy to recognise and is needed by the body, it is found in many foods and in many guises.

Salt is the base of life, as well as water and fire! Too salty however and the taste is repulsive, too much salt and it can be bad for the body, and will be rejected, many minerals are assimilated through this taste.

Sourness is a warning taste as most poisons are sour; in this category most medicines are sour, and the taste is well memorised generally. A pleasant taste is a harmonious combination of a few different tastes, as cited above, but well balanced.

It is interesting to be able to analyse the combination of wine and dishes, as the complementing wine will be the best one which will create the balance with the food. Therefore, the perfect dish has to be eaten without any wine as this would un-balance its taste and harmony. Obviously, this will be different from one person to the next as this is a body function, therefore controlled by each individual brain, experiences, backgrounds and prejudices.

• Transmission of the feeling of taste – per categories

Salt is sodium chloride; the detection threshold is very high at 0.01M.

Sourness is acid, this is detected because these are protons and they interact directly at cellular level with the cellular membrane. The detection level is medium at 0.0009M.

Sweetness is glucose, or sucrose (combination of glucose and fructose, and other carbohydrates). The detection is slower and more indirect than the other tastes, but the consequent impulse is strong and long lasting. The detection level is very high at 0.01M.

Bitterness causes a direct internal cellular reaction. The threshold is very low at 0.000008M.

Umami taste is detected via depolarisation of the cell at detection. This is the taste of certain amino acids, monosodium glutamate, and Soy sauce. Detection threshold is medium at 0.0007M.

Temperature sensation is defined by all the components in the mouth but is not a taste per se; pungency, very temperature-like, is often provoked by spices like ginger, black pepper, chilly, turmeric; whereas mint, menthol, or even camphor gives a feeling of coldness.

It is debated if fat could be classed as taste as it is more of a body function than a taste per se; as our body recognises fat when ingested but usually other tastes will be bound to the fat.

• The lingering effect of food

Commonly referred to as aftertaste, this could very be the ultimate definition tool of good food. In fact, when the aftertaste is well balanced and pleasant, then we can say that the food is good.

A typical food with a primordial quality defining after-taste is wine; you can definitely recognise good quality product this way. On the other hand, when a food is repulsive, you are left with a very unpleasant memory, and then the effect of after-taste is instructive: do not repeat this (remember taste is not flavour).

• Alterations of food

Some foods are made with artificial sweeteners. These substances are actually much sweeter on the tongue than natural sugar for the same weight.

Saccharin was discovered in the U.S.A. in 1879 at John Hopkins University of medicine by accident; as well Cyclamate was discovered in 1937 at the University of Illinois and Sucralose was found out at King’s College, London; aspartame is a recent discovery also contrary to stevia with have been known scientifically for over five centuries in Europe.

A World of Discoveries

Taste, like any human sense, is dependent upon each individual history. Appreciation starts early, babies and young infants learn to accept upon guidance almost any food. However, it has to be said that babies have a higher sense of taste than their parents and react quicker to bad sensations. If reticent, it suffices to let the child try repeatedly some food for it to be accepted, and remembered in later life, even if the baby does not like the food and eventually does not eat it.

However, if forced to taste and eat some food that is not liked at first, then rejection will be imprinted in the baby’s mind. Interestingly the body can dictate what food you like and when you feel like eating certain food, pregnant women are an excellent example of it. This is a natural function which try to make your brain realise that you need to ingest a certain category of food.

A percentage of the population, just above twenty, have less taste buds but are not overly affected by this discrepancy, however they are not passionate about food and only dislike a few. Accidents can happen and create ageusia, total loss of taste from the tongue, but this is extremely rare. More often hypogeusia occurs, a reduced ability, or dysgeusia, that is a distorted sense of taste, and can be created when you have a cold. Age, like for any bodily function has a detrimental effect on the function of taste.

Fascinatingly, taste changes over time. When young you will prefer simple soft taste, then you develop your taste, you begin with white wine, and change to complex reds. It is a natural progression. Therefore, the more you taste and the more you can analyse and recognise, the more you will tend to go for complex tastes. The other side of the coin in this instance is that it is difficult to go back and accept readily simple tasting food once you have sampled extraordinary food.

Geography is an important factor of taste. Depending on where you live in the world your body would have been engineered to recognise more easily certain food than others; and to react more to others as well. In the future, hopefully, this will diminish as population movement intensifies.

Obviously, the more you concentrate on food analysis, the more you can perform it adequately at a correct level. This does not mean that you are a “super taster”, just that you can educate yourself sufficiently to do something well. Nonetheless to say that people working with food have an educated palate and a high level of sensation, at least this is true of people who succeed in their field of choice.

Highly sensitive tasters are said to take more time to think problems through. Contrary to this, the “under-tasters” are more reliant on logic to solve their problems. This is directly related to the side of the brain concerned with food analysis. The more you use your brain the more you can use it! But this is not the subject, and this is not proved beyond doubt anyway.

In a restaurant or in a shop you will meet food educated persons well-rehearsed to talk about their own products. You should try to take advantage of this and discover new sensations. This will not work all of the time, but when circumstances and people are right, and open to each other, exchanges are possible and both parties will grow and develop *.

Evolutionary Examination

We have concluded the physical side of the senses analysis. Hopefully you now have a good grounding of the knowledge, and we can progress, in the few next posts, on the intelligent development of the understanding of the senses.

On a personal note *: when people learn to appreciate each other they benefit more from the association of their abilities, when people are free and educated, they mostly feel more able to partake and give opportunities to other people. When people have freedom of government and can think for themselves, their society is productive and happy, life feel good, it is worth doing and living…

And remember, give life to your taste buds, and above all, enjoy real cheese.