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The Elements of Wine Tasting Wine is usually drunk during meals but it is much more than an ordinary beverage. Good wine excites the senses with its color and texture, and its infinite array of aromas and flavors. When wine is drunk for this kind of aesthetic pleasure, it becomes an aspect of gastronomy. Wine drinking is also a convivial activity with ancient social traditions. Shared with like-minded companions, wine can inspire thought and discussion. The purpose of tasting (as opposed to drinking) is to evaluate the quality of a wine, on the basis of sensory impressions. A laboratory analyst uses scientific instruments to measure the quantities of the various components of a wine; a taster uses his own senses to give an evaluation of their character and quality. This skill requires the use of the senses of sight, smell, taste and touch. The evaluation of a wine follows a set procedure which has four main stages:
Sight: The Visual Examination Our sense of sight is activated by light rays which pass through the crystalline lens and the vitreous body of the eye to the retina where light-sensitive cells called rods and cones transform them into electrical impulses. These are then carried by the optic nerve to the occipital lobe, the part of the brain responsible for the interpretation of visual stimuli. The aim of the visual examination is to evaluate color, clarity, fluidity and, for sparkling wines, effervescence.
Smell: The Olfactory Examination The sense of smell is the key to enjoying wine, because it enables us to perceive both aroma and subtleties of flavor. When we sniff a wine volatile scented molecules pass into the olfactory membrane at the top of the nose where the olfactory cells convert the molecules into signals which are transmitted to the olfactory bulb locates at the base of the skull. This organ enables the brain to perceive not only odors inhaled through the nostrils but also conveyed to it from the palate by way of the nasal passage at the back of the mouth. The objective of the olfactory examination is to judge the intensity, length and quality of a wine's aroma, and subsequently to identify and describe the character of the specific odors of which it is composed. Intensity Length Character
Flavor and Texture Taste and Touch: The Gustatory Examination Gustatory analysis begins in the mouth and involves the interpretation of three types of sensation: Taste - Tactile sensation - Aroma. Taste: Tastes are mainly detected by the gustatory cells of the papillae
located on the tongue. These papillae are formed by hundreds of cells
known as taste buds which react with substances in the mouth sending
electrical impulses via a series of neurons to parts of the brain responsible
for registering taste sensations.
Tartaric, malic and citric acid are natural
components of grape juice. Succinic, lactic and acetic acid on the
other hand are produced by fermentation. Total acidity in wine varies
from 4-10 g/1. The sensation of acidity is second in the taste sequence
with a time lag of about 2 seconds and a persistence of up to 12 seconds. Bitterness: this is detected mainly at
the back of the tongue by circumvallated papillae sensitive to phenolic
substances including quinines, and ethyl acetate. The bitter sensation
is the last to be perceived with a time lag of about 3 seconds and
persistence of up to 15 seconds. This lingering effect accounts for
the bitter aftertaste described in certain wines. Tactile Sensations Practically all of the oral cavity has some sense of touch, but the parts most sensitive to the "tactile impressions" of wine are the upper, centre part of the tongue and the soft areas of the palate, the pharynx, the larynx and the gums. The centre of the tongue contains fluiform papillae that feel rather than taste and transmit signals to the brain. "Chewing" on a mouthful of wine is a technique which helps to accentuate the sensations of texture, temperature, astringency, body and the prickle from carbon dioxide in sparkling wines. Texture: this refers to the fabric of a wine, the way it feels in the mouth, often described by general impressions of touch. It includes for example the sensation of smooth, rich viscosity which is typical of certain dessert wines and is caused by the combination of sugar~ glycerin and alcohol. Astringency: is the dry sensation caused mainly by the tannins present in young red wines. The ageing process reduces astringency, and as a. result it is much less evident in mature and older wines. It should not be confused with the bitter taste which on the contrary increases with the age of a wine. Temperature: refers in this context to the sensation of warmth created by ethyl alcohol, which increases with the wine's strength. Body: is a term which expresses the sense of weight of a wine in the mouth. The impression of full-body is almost like that of chewing on something solid. It is created mainly by the dry extract (i.e. the components of the wine which are left after the liquids have been evaporated) and alcohol. Prickle: a prickly sensation is caused by the presence of carbon dioxide which accentuates the acidity of white wines and the astringency of reds, while reducing the impact of sweetness. Aromatic Taste Sensations The basic tastes of wine in the mouth are complemented by the aromatic qualities sensed by the olfactory system by way of the nasal passage at the back of the mouth. These aromas are conveyed to the olfactory bulb as the taster inhales through the mouth and exhales through the nose. This effect is influenced by several factors. The temperature in the mouth, which is warmer than that of the air, causes a slight evaporation of the wine which releases volatile scent molecules. Saliva, which is secreted liberally during tasting, chemically modifies certain substances in wine through a process known as hydrolysis which makes them odorous. The intensity of the sensation can be increased by pressing the tongue against the roof of the mouth in a movement which compresses the wine, again liberating odorous particles. Tertiary (or post-fermentation) aromas: comprise what is usually known as bouquet. The formation of these particular aromas is an integral part of the evolution of fine wine and they are generally most intense in mature wines. They are the result of the chemical action of enzymes on the natural components of the wine, and in the case of barrel-aged wines, those acquired from the wood. Recognition and Description Is at the same time the most fascinating, poetic aspect of analysis and the most difficult since it requires an "olfactory memory" capable of storing and cataloguing a considerable number of smells (above all familiar, everyday ones) and matching them with those in the aroma of a wine. It is important to remember that the sensitivity of the olfactory organs decreases with prolonged exposure to the same odor, to the point that we are eventually no longer able to detect a given smell, a phenomenon, known as "assuefaction". Finish The term finish refers to the final sensations a wine leaves on the palate after it has left the mouth. It is a key element in evaluating the overall quality of a wine. The main aspects of finish to consider are aftertaste and length. Aftertaste
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