Issue link: http://winesandvines.uberflip.com/i/122527
grapegrowing wines subject to counterfeit still rely on secret identifiers in the packaging for identification.) In summary, the complex relationships summarized above tend to undermine the idea that minerality is simply the taste of vineyard minerals in the wine. Tiny quantities of minerals in wine A critical difficulty for the idea that we taste the nutrient minerals in wine is the fact that their actual concentrations are typically minuscule. Potassium, being the primary mineral nutrient of vines, is an exception, but even this rarely exceeds around 1,000 parts per million (ppm), roughly 0.1% of the wine, and typically it is much less. In fact the total inorganic content of wines typically ranges between only 0.15% and 0.4%.5 The other main mineral nutrients present in wine are calcium, magnesium and iron, and these vary in concentration between a few tens and a few hundred ppm. Some wines have significantly less than this. In fact, if the nutritional content of wine was labeled in the way that U.S. law requires for most other foodstuffs, these minerals would be listed as zero. The other main nutrients—copper, zinc, selenium and the like—typically show concentrations measured in ppm at the most. Around 50 other inorganic components have been detected in wine, but most of these are trace and ultra-trace elements, with concentrations measured in parts per trillion. Such concentrations are so low that they barely exceed detection limits, even with modern analytical techniques. These tiny concentrations obviously conflict with the popular assertions that various wines are "mineral rich," "full of minerals," "laden with minerals," etc. Even so, minute though these numbers are, the real point is that these mineral elements have "PAY LESS FOR THE BEST!" ZB EMPLÉN ARRELS Trusted Source of the Premier Hungarian Oak 727 480-0914 727 255-4082 www.zbarrels.com Fine Wine Begins With Mueller ® Call us today at 1-800-MUELLER or visit www.paulmueller.com for all your winemaking needs! 66 p racti c al w i ne ry & v i ne yard MAY 20 13 no flavor anyway. Some may be detectable on the palate above a certain threshold, but usually giving an unpleasant sensation. In other words, coupling these minuscule concentrations with the fact that almost all minerals—in both geological and nutrient senses—are flavorless seems fatal to the idea of minerality in wine being simply the taste of minerals. Can we taste any minerals? Our mouths can only taste liquids. However, the geological minerals relevant to vineyards are solid and for all practical purposes are insoluble. Of the minerals common in vineyards only calcite (the constituent of limestone) has a significant solubility, but even here it is no more than about 47 ppm maximum. Hence, practically all geological minerals are tasteless. Licking a mineral or rock surface gives a tactile sensation, but this is not a taste. We cannot distinguish by tongue or by smell between freshly polished surfaces of different rocks (say limestone, granite or slate) or of minerals (say quartz, calcite or feldspar). The only significant exception to this is the mineral halite (sodium chloride, salt), which does dissolve to give the sensation of saltiness. Salinity, however, is to be avoided in vineyard soils, as is saltiness in wines. We perceive aroma (odor or smell)—with taste the other component of flavor—in our nasal passages. In order to reach the organoleptic receptors located there, a substance has to volatilize, that is, become vapor. Rocks and minerals cannot do this. The tendency for a substance to volatilize is indicated by a physical property known as vapor pressure, and this is substantial for many of the esters, ketones, aldehydes, etc., found in wine, which is why they are collectively called aromatic compounds. Their vapor pressure is measured in tens of kilopascals and more. In contrast, the vapor pressure of geological minerals and almost all nutrient elements is measured in a few tens of pascals at most. It is easily demonstrated that if we add mineral nutrients in the concentrations typical of wines, even to distilled water, we simply cannot perceive their presence. The business of drinking water quality has produced much relevant data. It is complicated, but the message is clear: even the lowest values for the detection thresholds in water are considerably higher than the ElectroSteam_June08 4/8/08 2:40 PM Page 1 concentrations normally found in wine.