The experienced taster, when called upon to give his opinion, looks at and attentively examines the wine. He then agitates it by shaking the glass, and, when necessary, places his hand round the glass in such a way as to warm the wine, thus favoring the volatilization of those matters which affect the olfactory organs; he then tastes it.
Sometimes the simple agitation of the wine by twirling the glass is not sufficient, especially when the sparkling and bouquet are to be particularly noticed. In this case the wine must be more thoroughly shaken, which is done by placing the palm of the left hand over the mouth of the glass, and then striking the bottom of it forcibly against the knee. This causes the wine to give off its odors, and in the case of sparkling wines its carbonic acid, more freely. The method, writes Ottavi, is not very polished or elegant, but accomplishes the purpose very well.
As can be easily seen the wine taster should preserve his senses, that is, those of smell and taste, with their utmost sensibility; this is only done by avoiding excesses of all kinds, for these in course of time are bound to diminish that sensibility, or to destroy it completely. Thus he must abstain from all highly alcoholic beverages, from strongly salted or flavored dishes, from tobacco in any form, and in general from everything that acts too energetically on the organs of the above-mentioned senses.
Physical indisposition, more especially affections of the nasal organs, the mouth, or throat, diminish or destroy all sensibility of the senses of taste and smell.
"Wine should not be tasted fasting, or it will taste weak and insipid; nor after drinking wine; nor with a full stomach. Moreover, the taster should not have eaten anything sour, salt, or bitter, nor anything which might change his taste; but he should have eaten a little, but not yet have digested it." -- Carlo Stefano.
The taster should not attempt to give his opinion of more than a certain number of wines at a time, as after having tasted a certain number the senses become temporarily much impaired and incapable of nice discrimination; nor should he judge of a wine after an abundant repast, as the various flavors of highly seasoned or sweetened foods have a great influence on the palate, and prevent it from judging a wine critically.
It is a well-known fact that after eating sweet fruit a wine seems to be rougher and harsher than it really is, whilst cheese, nuts, artichokes, etc., make it appear smoother and more delicate.
With piquant cheese, like Parmigiano and Roquefort more especially, which Grimod de la Reyniere has called "the tippler's biscuit," all wines seem good, or at least much better than they really are. It is also true that strong and badly tasting wines when drunk undiluted destroy the sensibility of the palate; people habituated to these wines end by being unable to find any taste in the fine wines of delicate flavor which are the delight of the connoisseur.
Tasters who are accustomed only to high-class wines, when they taste ordinary or low-class wines are apt to underrate them, if they do not reject them as altogether valueless, though they may be sound and clean tasting. On the other hand, tasters accustomed to ordinary wines almost always deem the prices paid for high-class wines excessive.
This suggests the importance of habit as a factor in the modifications which the taste may undergo. It may easily happen that the prolonged use of a substance may render the sense of taste obtuse, and that the tongue may become " saturated," as Brillat-Savarin says in one of his happy aphorisms. Thus, when the palate has become habituated to a taste, that which at first was intolerable becomes often pleasing and even necessary. Generally, however, habit educates the sense of taste and renders it acute.
Sometimes a taster is called upon to give an opinion as to the character, the good or bad qualities of a wine of a certain locality or of some particular producer or vineyard; in this case, even though he may be well acquainted with the kind of wine, to be able to give his decision with more confidence, he will carefully provide himself with a wine of the same type as that which he is called upon to judge; he can thus receive material aid by making a comparison.
Naturally, a taster who is used to the wines of a certain locality or country will be more easily able to detect the slightest differences between the wines of that locality, especially those differences in fine wines which distinguish wines produced by different vineyards even in the same locality, and when planted with the same varieties of grapes.
A taster should be very cautious in giving an opinion of a young wine, or of one whose origin is unknown, and of pronouncing on its intrinsic worth; the youth of the wine will often mask defects, which, later, become apparent.
When it is found necessary to taste several wines in succession, it is a good practice to eat a little dry bread between each wine, or to rinse out the mouth with a little fresh water, to neutralize the palate, so to speak.
It is always good to rinse out the mouth with fresh water before commencing to taste.
Before commencing the tasting, or rather the final tasting that on which is based the concluding judgment the wines should be sorted; for example, if the wines are of the same kind, but of different ages, it is best to begin by tasting the weakest, thinnest, or greenest wines, reserving the maturer wines and those which are more 'aromatic, smooth, or alcoholic for the last.
The same is true when there are many and diverse wines, as at an exposition. In this case the tasting proper should be preceded by an arranging of the various wines, a thing which is not done at all, or badly done as a rule, much to the detriment of the exhibitors. This selection should be based not on the labels on the bottles, or on the statements of the exhibitors, but on a preliminary tasting; in this way those who are to judge the wines will not be presented successively with different type's of wine, with wines of different qualities and ages together, and, as is unfortunately the case, sometimes with defective or bad ones.
There are tasters who are ready at any time to pass judgment on a wine; they will even taste directly after smoking. Their opinion, to say the least, is of little value.
A good taster is not always in condition to exercise his art, and for that reason must sometimes refuse to make a tasting when he does not feel in a state to judge critically.