Fragrances determine our life, as well-known gastronomy and wine expert Guy Bonnefoit in his book "Fascinating Wine & Flavors" writes: The human skin has a surface of about two square meters and has up to 300 odor components. Depending on the physical condition and mood, the odors change as well. A dog can make a precise distinction between people who are well-disposed and anxious to meet it. Every mood has its own smell. You can smell happy. An experienced country doctor reports that he is able to recognize certain illnesses when entering a sickroom. Every disease develops its typical "scent". Diabetes smells fruity, diphtheria sweet, typhoid after baked bread and gout after lion cage or pet shop (end of quote).
The sense of smell is the ability to perceive gaseous substances or substances dissolved in water at the molecular level. Again taste the smell is one of the chemical senses. The ability is only detected in vertebrates and insects. Odor sensations are much more emotionally charged than any other sensory organs. This means that immediately a rating in pleasant (smells) or unpleasant (smelly) takes place. In behavioral biology, the odor has a special meaning in terms of food intake, reproductive behavior and recognition of enemies. Odors promote the appetite and the formation of digestive juices. And the statement "that you can not smell someone" is much more than just a pun.
Scientific experiments have shown that in the partner selection, the smell unconsciously has a great importance. Odors also play an important role in memory and associative brain processes. Smells become olfactory over the yellow olfactory mucosa (about 2 x 5 cm²) in the uppermost part of the nasal cavity just below the brain. Fragrances are not only nasally (orthonasal, pronasal) when inhaled through the two nostrils, but also retronasally exhaled from the oral cavity through the nasopharynx to the olfactory mucosa and perceived. It depends on the amount of an odorant when it is perceived. This is called Perceptual threshold (Border).
Around 20 million scents absorb the fragrances. A dog possesses ten times more olfactory threads, that's about 200 million on 2 x 25 cm². These absorb the smell, act as receptors and pass them on to the olfactory bulb. Here they are first perceived and forwarded to the brain for "dissolution". Women have about 50% more nerve cells in the olfactory bulb and therefore a better sense of smell. The olfactory brain (rhinencephalon) lies as a delimited part below the right cerebral hemisphere and is connected to the limbic system (limbis = addition). This is responsible for all emotional processing such as love, sexual arousal, fear and anger. As in the wine also numerous pheromones (Sexual fragrances), wine may well be considered aphrodisiac Act. At the olfactory perception are however two sensory Involved systems. This is beside the olfactory also that trigeminal (concerning the sense of touch) system.
A severe limitation is a cold, in which one perceives the taste directions, but no odors. Odor impressions are falsely often the taste attributed. Because while enjoying food and drinks as well as of course Weingenuss These impressions of the tongue and nose, which are first received in the brain, combine to form an overall impression, so that the definitive origin can no longer be comprehended. The combination of taste and smell sensations creates a complex variety of sensory nuances. The human tongue is downright primitive with its six taste directions opposite the nose. Richard Axel and Linda Buck were awarded the 2004 Nobel Prize in Medicine for a detailed understanding of the sense of smell. The two US researchers showed that humans can absorb, remember and differentiate around 10,000 odors.
To detect the smell, the concentration of the fragrance must be about 50 times higher. Fragrances can belch the gates of memory. But civilized people have forgotten how to identify odors precisely. Because we do not need this anymore as in primeval times, where survival depended on it. In addition, according to one hypothesis, the human being, as he "straightened up", lost some of his sense of smell and at the same time increased the performance of seeing and hearing. Nevertheless, the nose is still much closer to our psyche than the eye or the ear. In the wine cause the numerous flavorings the fragrance impressions. Of the University of California became the so-called aroma wheel developed with the help of which these fragrances can be identified. In normal breathing, only a small portion of the fragrances reach the receptors. That's why you have to go to one wine review "sniff" with your nose deep in the glass. However, this should not be done too intensively, otherwise the fragrances will pass the olfactory mucosa and will not be absorbed there.
At the end of June 2014, the following press release was issued by the Technical University of Munich (TUM): "Odor code of food decrypted". Scientists from the TUM and the German Research Center for Food Chemistry (DFA) conducted a meta-analysis of the odor pattern of 227 food samples. The study clarified and identified the molecular fragrance signatures of foods. More than 10,000 different volatile substances are found in food. But only about 230 of them characterize the aroma of the most common foods. And only three to 40 of these key flavors encode the typical and distinctive fragrance of a single food from pineapple to roast meat to Wien . For example, the scent of sour cream butter is coded by a combination of only three key molecules, 12 being the fresh strawberry and the leader in the field cognac with 36.
The chemical odor codes are translated into olfactory stimuli when eating food. This requires the key odorants to interact with one or more of the 400 olfactory receptors in the nose. Prof. Thomas Hofmann (Chair of Food Chemistry and Molecular Sensing) notes: "The combination of just a few key aromas creates an authentic sense of smell. However, the odor quality of the combinations is not determined by the individual components. In the perception and neural processing of the odor patterns, the individual aroma components do not simply add up. Rather, the individual information is translated into a new fragrance form. Given the combinatorial nature of the chemical flavor code and the plethora of around 400 odorant receptors, the number of perceivable odors appears to be nearly unlimited. "
The identification of odor codes opens up completely new possibilities for biotechnological applications. For example, at the breeding It may be helpful that the aroma codes of crops and fruits are known at the molecular level: In the past, breeding was less on the sensory quality than on the increase of earnings and area performance aligned. The findings also provide the scientific basis for the next generation of bio-aroma production, which exploits the potential of optimized biosynthetic pathways in plants for the industrial production of high-quality food odorants.
The current odorant mapping also allows the natural reproduction of aromas with increasing precision. This brings completely new applications in mobile communication systems such as the transmission of odor news with the smartphone or even in the development of bioelectronic noses within reach. (Publication: Andreas Dunkel, Martin Steinhaus, Matthias Kotthoff, Bettina Nowak, Dietmar Krautwurst, Peter Schieberle and Thomas Hofmann; Genuine Odor Signatures of Nature, Perspectives from Food Chemistry for Future Biotechnology, Angewandte Chemie).