A glass, when it is shaped in particular forms is also known as wineglass, is a container whose purpose is to hold a liquid substance, wine in our case, and by watching its apparent simplicity, it can also be considered as an accessory having little importance: the only property it seems to have is the capacity to hold a liquid and an opening on the top in order to let this liquid get into the mouth; it does not seem to need anything else to do its job. However, despite its apparent simplicity, glass plays an essential and determinant role during wine evaluation, first of all, it plays a fundamental role during the evaluation of one of the most exciting and amazing aspects of a wine: its aromas. Last but not the least, the shape of a glass also contributes to develop, or better, to give a higher priority, to the perception of specific tastes and allowing all the others to be perceived next.

 While gustatory perception of a wine by means of a glass depends on the habits everyone has to introduce a liquid into the mouth, perception of aromas is accomplished, generally speaking, in the same way and with the same conditions by anyone. If you happen to watch a person while he or she drinks a liquid from a glass, you will notice that some of them suck the liquid, other allow the liquid to fall into the mouth, and others, with their lips almost sealed, suck with force the liquid into the mouth and, by doing so, they actually break the liquid mass with the result of a strong oxygenation of the liquid. The shape of the glass, compared to the gustatory perception of each person, greatly varies according to the ones who make use of it, just because of the habits and customs every one has to drink a liquid from a glass, except when exact instructions on how to use a glass are provided and these instructions are scrupulously followed.

 The fundamental importance of a glass is mainly associated to the perception of aromas, last but not the least, to the evaluation of its aspect as well. The vast availability of glasses on the market, coming in many and different shapes, is well known to anyone, every glass producer continuously introduces new kind and styles and most of the times they also end up to create a sort of confusion and doubts about when using that particular glass or how to use a glass with a particular wine. Glass has a determinant importance during the organoleptic analysis of a wine, this is absolutely true and indisputable. However, one can be puzzled by the fact that professional wine tasters, that is those competent people who should pay a scrupulous attention on setting and arranging the best conditions when they are about to taste a wine, do not make use of a wide variety of glasses. Every wine taster, at least the professional ones, agree on the fact that to properly evaluate organoleptic qualities of a wine, that is the particular activity which requires the best conditions possible for analyzing a wine, is accomplished with success by using only one and particular kind of glass and always having the same shape: the so called ISO tasting glass (See figure )

 If one considers the huge amount of glass shapes available on the market, each one surely having a proper function and purpose according to any particular kind of wine, it can be seen as a paradox the fact that the ones who professionally determine the quality of a wine always make use of the very same type of glass. Indeed, no matter how versatile and perfect it can be, this glass has a limit for the evaluation of the appearance of lightly-sparkling and sparkling wines, however, we will see later, this glass can be used with success for this purpose provided it is properly “modified”.

 The secret of the “success” for this glass is based on a long series of experiments and studies that finally led to the determination of the best and useful shape suited for the development of aromas and their best evaluation. One of the main researchers who allowed the definition of this particular and efficient glass is Mr. Jules Chauvet, a talented and esteemed wine taster and wine maker from Beaujolais, France, whose studies, conducted during the years of 1950 and based on the theory that volume to surface ratio of a glass has a direct connection with the development of aromas, have greatly contributed to understand the importance of the shape and of volume of a glass and led to the creation and determination of the characteristics and specifications of the ISO tasting glass. The typical shape of this glass is commonly referred as “stretched egg” and thanks to this particular and stretched shape and to its dimensions, result of exact and scrupulous ratios, wine aromas can better develop and express. Another fundamental characteristic of this glass is its opening, narrower than the body, which allow aromas to be concentrated in a more limited area and however sufficiently wide in order to allow the nose to accomplish a correct and useful olfactory analysis.

	ISO tasting glass filled at 50ml (1½÷1¾ fl.oz)

 The dimensions of this particular glass, loyal fellow of any wine taster, was defined and determined by the International Standards Organization, ISO, and are specified as shown in figure .

Dimensions of ISO tasting glass

 When this glass is correctly filled, that is when it contains a quantity of wine of about 50ml (1½÷1¾ fl.oz), wine creates a perfect hemisphere where the surface wine-air is in perfect relation, both logic and geometrical, with the volume of the wine under this level and a sufficient air space above it is determined in order to allow aromas to get fully developed, this process is also promoted by the sides of the glass that concentrate smells to the opening, therefore to the nose. Air surface to wine volume ratio has been carefully studied in order to prevent as much as possible the development of “coarse” aromas, giving a higher priority, so to speak, to refined and elegant aromas.

 The ISO tasting glass, whose specifications have been defined in the first years of the 1970, must be made of transparent glass, no color, and it will be made of “half-crystal”, that is having a percentage of lead of about 9%. Dimensions should exactly be as the ones indicated in figure and its capacity will be of 210 ÷ 225 ml (7½ ÷ 8 fl.oz). Besides being transparent and having no color, this glass must not have any decoration or facets: its aspect will absolutely be smooth and clear in order not to distract the taster during the evaluation of the appearance of a wine as well as not to present the wine under a false aspect. This characteristic is valid for any glass used for drinking wine, not only to the ones used for the evaluation of wine. Despite the fact this glass seems to be so perfect, according to the description we gave so far, it is actually not well suited for the evaluation of the appearance of sparkling or lightly sparkling wines. This glass has been designed in order to allow the full development of aromas and it has a proper surface to promote this, however this surface is too wide and cannot properly keep carbon dioxide (CO₂) of sparkling wines, the effect is that carbon dioxide is rapidly released and the “perlage” does not last that long. This is the main reason why, for example, sparkling wines are usually served in “flûte” glasses, which have a narrow diameter and the carbon dioxide is released more slowly and therefore lasts longer. The ISO tasting glass can be properly used with success in tasting sparkling wines, their aromas will surely be enhanced and developed, provided this glass has a little emery point, of about 5 mm (a little less than a quarter of inch) in the bottom and in the center of the body. This “trick” will properly allow the development of carbon dioxide.

 After having bought a ISO tasting glass, it can be easily found in wine shops or in shops who sell glassware, you need to properly wash your new glass before using it. As a general rule, and this rule will be valid and used every time the ISO tasting glass is being washed, soap will never be used. To understand the reason of this apparently unhygienic rule, one should consider the characteristics of soap. The first drawback is represented by the perfumes found in every kind of soap; these perfumes, surely pleasing, would be easily perceived during the olfactory analysis of a wine, in particular, in any delicate and light wine. One should remember ISO tasting glass has been designed in order to promote the full development of the aromas in it, of course, this principle is also valid for any other smell found in the glass, not only the ones of wine. The second drawback in using soap is represented by the thin and invisible film which is left on the side of the glass, in particular on the inner sides of the glass, and this film will drastically alter the surface tension: the wine will “slip” more easily along the sides of the glass therefore altering the result of part of the analysis of the appearance. So, no soap and therefore no dishwasher.

 The first wash of your new tasting glass starts by rinsing the glass with hot water, and then it will be washed with pure vinegar. Make sure vinegar will wash every part of the glass, in particular the inner side, wash your glass accurately and thoroughly with your hands and with fingers wash the inner part of the glass. Also make sure not to use too much strength or twist movements as the glass could easily break. The best way to hold a glass while it is being washed is to grasp the body of the glass with the palm of the hand and having its stem between the forefinger and the middle finger, while washing it on the inside and on the outside with the other hand. It is strongly not advised to hold the glass by its base, or even worse by the stem, because twists and strength used to handle the glass could easily break it. After having washed the glass with vinegar, this operation will remove any fatty substance and residuals of production, a thoroughly rinse will follow, still using hot water and this will eliminate any trace of vinegar including its strong odor. Final rinse of the glass should be done by using distilled water in order to wash away any calcareous trace as well as chlorine which could be present in the water used to wash the glass. The glass should be drained by leaving it upside down. In case distilled water was not used for the final rinse, it is advisable to dry the glass by using a clean cloth in order to completely remove water which could leave calcareous traces. When using a cloth, particular attention must be paid to any possible smell of it, usually odors of the soap used to wash it. The best thing to do is to always use the same cloth, hopefully used for drying your tasting glasses only. In this case, the cloth must not be washed with soap in order not to leave any unwanted soap odor in the glass.

 As we have a properly cleaned tasting glass, we can start using it. The very first thing to do before using it is to make sure the glass does not have any extraneous odor, for example, in case the glass has been kept in a box made of cardboard, it may happen to find a smell of cardboard on the inside of the glass. Always smell your glass before using it and make sure it has no odors. In case the glass has some extraneous odor, it can be quickly rinsed with water and then it will be dried. In case the glass cannot be rinsed because of lack of water, here it is a useful “trick” that can save your glass. Blow in the glass and then breathe in its inside. Smell the glass again: it is likely odors have been attenuated or, in best cases, they are disappeared.

 Before tasting a wine with your glass, it is advisable to rinse it with wine. This simple procedure will prepare the glass to receive wine and to eliminate any possible odor from the inside of it. Start pouring a small quantity of wine, the very same wine to be tasted, and holding the glass by the base and the stem, never by the body in order not to smear the glass, rotate it in order to let the wine to completely wet the inside. When the glass is perfectly wet with wine, empty the glass and discard the wine. As soon as this operation is done, the wine to be tasted can be finally poured into the glass. The right quantity of wine to be poured should be 50 ml (1½÷1¾ fl.oz), anyway not more than 60 ml (2¼ fl.oz), in order to make the best use possible of the technical characteristics of the glass, the characteristics that allow a proper and efficient development of aromas. Anyway, the glass should not be filled with more than 100 ml (3½ fl.oz) of wine: besides diminishing the development of aromas, it also makes difficult to swirl the glass without not spilling the wine out and therefore it cannot be properly oxygenated. For your reference, the glass in figure is exactly filled with 50 ml (1½÷1¾ fl.oz) of wine. This level is also shown in figure : it should be noticed that this level corresponds about to the point where the body of the glass reaches its widest diameter.

	How to grip the tasting glass

 After having poured some wine into the tasting glass, we are ready to take it and to start evaluating the wine. Even though the act of taking a glass with the hand could be seen as obvious and banal, indeed there are some ways that should be used every time this special glass is held with the hands, this grip also applies to any other wineglass. Let's see how not to hold a glass: a glass will never be held by the body. Despite any consideration that could be said about the scarce elegance of holding a glass by the body, there is another and more important fact that should be considered by anyone who is going to taste a wine: the heat of the hand would warm the wine and, as we learnt in the previous issue, temperature is a determinant factor for a proper evaluation of wine. Besides this, it would make things difficult during the analysis of the appearance of a wine, as the hand would not allow the wine to be seen. Another reason that would be considered when holding the glass by the body is that the olfactory analysis would be altered by any possible odor of the hand and these odors would surely disturb the whole process and some aromas of the wine could also be ignored. In consideration of all the above, the first rule to be followed when holding a glass is that the hand must be held as far as possible from the body of the glass and therefore from the nose. The tasting glass, or better saying, every wineglass, must be held by its base or by the part of the stem near the base. The preferred grip is by the base, with the thumb over the base and near the stem while the forefinger is held curved under the base. Figure shows the correct and right way to grip the tasting glass.

 A correct grip of the tasting glass makes things easier when the glass is to be swirled in order to promote the development of the wine's aromas. This important movement is achieved by rotating clockwise the hand holding the glass, in order to have the wine to go up to the side of the glass; this operation will increase the surface of the wine in contact with air and by doing so a better and increased oxygenation of the liquid is obtained as well as a better development of the aromas. (See figure ) The curved shape of the sides prevent the wine to spill out from the glass, provided this movement is not achieved with much strength. Holding a glass in this way also allows a more comfortable and easy movement of the wrist, in particular, when the glass is to be tilted in order to assess the color and the tint of wine.

 When correctly filled, the height of the body of the glass allows to keep the nose at the right distance from the wine and, when correctly held, the glass allow the hands to be kept at a sufficient distance both from wine and nose. A very important characteristic of this particular glass is the diameter of its opening. As can be seen in figure , the opening is narrower than the body and it is sufficiently wide in order to have enough space for the nose and prevent too much air to be inhaled from the outside of the glass therefore ensures that most of the air inhaled comes from the inside of the glass. This characteristic, determined in this glass by an exact ratio, is generally common to any wineglass: the body is always larger than the opening and the sides are always curved in order to concentrate aromas to the opening and therefore to the nose.

 Sometimes it may happen that there are no more fresh glasses available to taste a determined number of wines. In this case one may use again glasses already used, provided they are rinsed with some wine, the wine to be tasted, as explained above, in order to eliminate any previous taste or aroma in the glass left by the previous wine.

 After having used the tasting glass, a thoroughly and accurate wash is needed in order to keep the glass in perfect state and condition for the next tastings. We already talked about how to wash a tasting glass for the first time; the same rules also apply to this case with the exception of some small differences. In this case vinegar will not be used, the glass will washed with hot water only. Washing the tasting glass in this way is enough in order to remove any trace or smell of the wine. Particular attention should be paid to fingerprints and lipstick traces, however it is advisable for ladies not to use any lipstick during a wine tasting in order not to alter the sensorial perception of aromas and flavors. In case this traces are hard to remove, we can use the same procedure used for the first wash of the glass; it can be washed by using some vinegar. After having washed your glass with vinegar, an accurate rinse with hot water will follow and the final rinse will be done by using distilled water.

 After having washed the tasting glass, the next thing to be done is to dry it. In case distilled water has been used, the glass will be left upside down in order to completely drain. This is the best way to dry a glass and it should be preferred to the use of clothes because they could leave some odors in the glass, mainly odors of the soap used to wash them, as well as leaving lints on the inner sides of the glass that would disturb the evaluation of the appearance of a wine during the next tasting. Cloth is to be used only when the glass has not been rinsed with distilled water, and in case a cloth has to be used, it will be better to use one that does not leave lints and has been washed with the least perfumed soap possible. The best solution is to make use of a cloth exclusively destined to this purpose, in this case the cloth can be simply washed with hot water and no soap, as the sole operation of drying clean glasses does not get it dirty.

 Rinsing a glass with distilled water is a good way to remove any possible trace of chemical compounds that may be dissolved in water, such as chlorine, any possible water's odor as well as calcareous traces present in water. If the tasting glass has been washed with calcareous water and it would be left to drain, the sides would be stained with whitish calcareous stains, surely not much attractive as well as not useful when the wine's aspect is being evaluated. This is the reason why a cloth may be used to dry glasses not rinsed with distilled water, however, it should be remembered a cloth may leave lints as well as odors in the glass.

 After the tasting glass has been properly washed, particular care must be taken for its storage and it must be kept in a proper place. Any place, including furniture, boxes, containers having strong smells must be avoided in any case, because such odors would be transferred to the glass as well. In case you choose to keep your glasses in a piece of furniture or in a container, such as a box, the glasses must be kept upright. In case glasses are kept in special containers, such as a case, it is best to make sure this does not have any odor, in particular chemical odors. However, before using any tasting glass, it will always good to smell it and make sure it does not have any odor, to be more clear, the tasting glass must have no odors. In case a tasting glass has some extraneous odor, it is best to do what we already said above. In case tasting glasses are not used for a long time, it is good to regularly wash them from time to time, anyway, they will be thoroughly washed before making use of them and they will also be rinsed with wine.

 Even though the methods illustrated so far for taking care and keeping a tasting glass to its best condition may be considered as maniacal and excessive, bordering paranoia, one should remember that thanks to this important tool a wine can be properly evaluated; this is the main tool for anyone who wants to seriously evaluate the organoleptic characteristics of a wine, therefore it must always be kept in best conditions and state. A bad glass will surely alter the evaluation of a wine and it will not allow a proper, honest and objective job to be done. Every professional wine taster, however any wine taster who deserves to be considered as a professional, takes excellent care of its tools and the ISO tasting glass is the main wine taster's tool. To make things clearer and to understand this concept, let's suppose a wine taster is about to evaluate a wine having light and delicate aromas. Let's also suppose that the wine is being tasted in a glass washed with soap and kept in a piece of furniture used to keep foods having strong smells. As a first consequence, the delicate and light aromas of that wine will not be perceived at all as they will be hidden by all the other smells present in the glass because of a bad care, moreover, the wine will be considered to have “improbable” aromas for its type, odors that could also be considered as defects, whereas those smells are not present in the wine at all.

 The ISO tasting glass is an essential tool for the proper evaluation of a wine and for a proper organoleptic analysis, it was expressly studied for this purpose and it is derived from a long and hard research; however when it is not treated with proper care, the only thing it can do is to do a very bad job, surely not because of its fault, but surely because it has been treated improperly and the only one responsible for this is the owner. A serious wine taster is also a person who takes excellent care of his or her tasting glasses.