Postmodern Winemaking Glossary
Anthocyanins Top
These are the phenolic building blocks which when extracted from grape skins give red wine its color. They are also critical to good red wine structure. These compounds act as the “book ends” on the polymerization process, so the more of these we extract from the grapes at harvest, the softer and finer the tannins will be. Anthocyanins are, unfortunately, not very soluble in wine, so they must be extracted in the form of copigmentation colloids. Since they are positively charged, anthocyanins cannot aggregate by themselves, but require monomeric (unpolymerized) tannins to be present to assist the formation of these colloids, which provide a temporary home in new wine for color compounds. From there anthocyanins can become a stable part of red wine through oxidative polymerization and aldehyde bridging, both artifacts of oxygenation. Excessive hang time depletes anthocyanins through field oxidation, and is thus deleterious to good structure and longevity. More about Anthocyanins
Anti-oxidative vigor Top
See reductive strength.
Aromatic integration Top
The phenomenon of merging together the complex elements of a wine or food into a unified “single voice” through refined structure. The resulting soulfulness is similar to that achieved by a symphony orchestra when all the musicians are in sync. We are moved by structured foods such as lobster bisque, chocolate and bearnaise sauce when a well prepared, fine particle size is achieved, resulting in the merging, for example, of the tarragon, fresh onion, mint and vinegar aspects into a single “bearnaise” flavor. Similarly, properly made wines never need to be over-oaked, obnoxiously vegetal, or unpleasantly alcoholic. Well structured wines can also be improved by microbial activity rather than exhibiting spoilage characteristics. More about Aromatic integration
Brix Top
Percent sugar by weight present in the juice of grapes. Easily read in the field by refractometer, it relates closely to resulting alcohol content after fermented to dry wine. Due to climatic influences of temperature, dew and rainfall which vary widely from place to place and season to season, brix is an unreliable indicator of ripeness, which is more closely related to the completion of Cycle Two metabolism. More about Brix
Cliqueage Top
The introduction of oxygen in tank or in barrel by instantaneous injection rather than the slow, continuous infusion that characterizes micro-oxygenation. The term derives from the “click” sound of a radio-actuated solenoid switch which cellar workers use to facilitate a timed burst of oxygen as they climb around the barrel stack and drop the diffuser into barrel after barrel, added to the “-age” ending that in French denotes a process (accented on the second syllable as in "montage"). The results of cliqueage are as opposite to micro-oxygenation as scorching is to simmering. Cliqueage pushes a wine along by breaking down its anti-oxidative power and polishing its tannin, while slow oxygenation builds structure and reductive vigor. More about Cliqueage
Coextraction Top
A technique for facilitating the extraction from grape skins of otherwise nearly insoluble flavor and color compounds which need assistance to form colloidal beads. The assistance comes from the infusion of monomeric phenols from tannin-rich varieties, often from white grapes. Garnacha in Rioja is assisted by co-fermentation with the skins of Palomino; Syrah in the Rhône with Viognier, Sangiovese with Trebbiano and Malvasia, mistakenly often supposed only to add aromaticity. Other materials such as untoasted oak, if well cured, can assist extraction, including teas of stems or seeds. Powdered tannins are polymeric and thus have no co-extraction benefits. More about Coextraction
Cofactor concentrate Top
A fraction prepared by ultrafiltration which has high co-extraction power. Press wine, high in tannic colloids, is circulated against a filter enough to exclude colloids until the end of the run when the concentration of retentate thickens to the point that the colloids merge into a tar and the small phenols which cement them come through into the permeate as a concentrate which may be added in very small amounts to a fermentation to facilitate co-extraction of flavor and color to enhance varietal and terroir expression. More about Cofactor concentrate
Colloids Top
Microscopic suspended beads which form in aqueous solutions, generally composed of materials which are not very soluble but which have affinity for each other and can build stable microscopic structures. Phenolic substances form colloids in wine, and almost all the color and tannin of red wine resides in its colloids. Young red wine forms unstable copigmentation colloids which assist extraction. Oxidative polymerization, if properly orchestrated, can transform these into stable colloids composed of short polymers containing pigment. The finer these colloids are, the more they assist aromatic integration and the resulting soulfulness.
Copigmentation colloids Top
Young, unstable colloids formed in red wine during fermentation on skins from roughly equal quantities of monomeric uncharged phenolics and monomeric anthocyanins. More about Copigmentation colloid
Copper Top
An elemental metal which is used (generally dissolved in the form of copper sulfate) to react with sulfides, but which also acts as an oxidation catalyst, thereby short-circuiting reductive strength and diminishing longeveity. It is a goal of postmodern winemaking to eliminate the use of copper.More about Copper
Crossflow Filtration Top
(Also called tangential filtration.) Any of a family of tight (sub-micron) filtrations in which tangential flow is used to scrub the membrane to reduce fouling. In these strategies the majority of wine is diverted across rather than through the membrane and returned to the feed tank (retentate) while a small percentage of the feed flow passes through the filter (permeate). These include (in descending order of tightness) crossflow clarification, ultrafiltration, nanofiltration and reverse osmosis. The term is often erroneously employed as an abbreviation for crossflow clarification only.
Cycle Two Top
The second cycle of grape maturity, during which grapes transform themselves from a bird repellant to a bird attractant, the essence of ripening. Grapes complete Cycle One at about 12 brix (a ripe tomato is only 8 brix by comparison), so it is essential that they prevent consumption as a food for birds until the seed matures. Grapes accomplish this through strategies that render them invisible and undesirable: they are small, hard, bitter, low in flavor (except the bell pepper vegetal flavor camouflage resembling a leaf or stem), tart, harsh and green. During Cycle Two they transform in six to eight weeks into big, soft, sweet, flavor-filled, highly colored berries with softened tannins and low vegetal aromas.
The balance required to achieve good tannin structure includes adequate levels of flavonoid phenolics coupled with a good supply of unpolymerized anthocyanins from grapes which have experienced a healthy Cycle Two, were harvested ripe but not overripe, and were extracted properly into copigmentation colloids. Good color is the key to good structure. More about Cycle Two
DAP Top
Diammonium Phosphate, an inorganic fertilizer routinely added to fermentations to assure vigorous yeast activity and alleviate sulfide production, a cheap magic trick novice winemakers employ to please their bosses. Postmodern practice discourages its use. Sulfide production during fermentation is normal and seldom leads to sulfides in the resulting wine. DAP, on the other hand, leads to vigorous but incomplete fermentations and sidetracks yeast from creating a nutrient desert beneficial for control of secondary microbial activity in the cellar (IBM). If we feed the yeasts Twinkies, they won’t eat their oatmeal! More about DAP
Field oxidation Top
The practice of resolving tannins through extensive hangtime. Similar to micro-oxygenation, but without the precision which can be accomplish in the cellar. Micro-oxygenation seeks to build a tannin soufflé, impossible if the egg is already scrambled when it arrives in the kitchen! Instead of enhancing structural stability, aromatic soulfulness and longevity, field oxidation usually leads to premature fruit-forward characteristics followed by oxidation, VA, and dryness. Three weeks excess in the vineyard robs to a decade or more in the cellar. More about Field Oxidation
Flavonoids Top
A class of phenolic compounds uniquely extracted from skins and including red wine color (anthocyanins and polymerized pigment) as well as tannin building blocks.
Framing Top
One of the seven functions of oak identified in the postmodern system. For wines possessing a rich core of fruit, sweet oak can lead to imbalance. Rather, these wines should be cellared with wood which imparts structure and angularity. Several coopering approaches assist framing. Oak from pedunculated species, or grown in copse habit will tend to be rich in ellagitannins which impart framing. Light toasting (spiciness) or very heavy toasting (espresso coffee aromas) are useful for framing. Untoasted wood (coconut) and moderate toasting (vanilla) contribute sweetness and should be avoided for this purpose.
Hyper-oxygenation Top
Introduction of large amounts of oxygen to musts prior to fermentation. While all musts require oxygen to promote yeast health, hyper-oxygenation goes beyond this requirement and seeks to promote oxidative browning, polymerization, and precipitation of tannins, usually from white press wines. It has no relation to micro-oxygenation. More about Hyper-oxygenation
Ideal SolutionTop
In the late 19th Century, scientists constructed a simplified model, termed the dilute aqueous solution model, to crudely describe the behavior of such systems. The intention of an idealized model is to roughly predict solution behavior, which is then adjusted to observed phenomena through the addition of a patchwork of correcting terms. In practice, for a solution as complex as wine, this correctional work is usually neglected, and the assumptions of the ideal model are taken as a rough guide. Solution-based thinking has shaped the modern view of wine and how we work with it by bringing to bear the powerful tools of analytical chemistry, chemical engineering, and sensory science.
In 1882, Raoult’s Law stated that the volatility of a compound dissolved in an ideal solution is a function of its concentration in the solution and its natural tendency to volatilize (its Henry’s Law partition coefficient). This means that if wine is a solution, its sensory properties derive from the concentrations of substances dissolved in solution. The greater the concentration in the liquid, the more intense its odor and taste. If this relationship is exactly linear, the solution is said to behave “ideally.”
One of the precepts of solution chemistry ideal behavior is that the concentration (in, say, milligrams of material per liter of solution) is proportional to that found in the headspace, i.e. the aroma in the glass. We speak of a threshold as the average minimum concentration which a group of subjects can smell. When most winemakers discuss intensities of aromatic elements, they speak in terms of the dissolved concentration in the liquid, not the amount of material in the gaseous headspace they are actually smelling, which is more difficult to measure. The notion of a threshold expressed in this way pre-supposes that Raoult’s Law is approximately correct, an assumption which postmoderns emphatically reject as inapplicable to red wine. The presence of colloids is the cause of strong deviation from “ideal” solution behavior, and the source of aromatic integration and soulfulness.
Integrated Brett Management (IBM) Top
A strategy analogous to IPM, but applied to microbiological ecology in the cellar. This method seeks to stabilize wine through playing out potential microbial activity in the cellar so that stable wine can be bottled without sterile filtration. Brettanomyces yeast, which in conventional modern wines can impart objectionable earthiness, is controlled through a triple strategy involving complete fermentation to a nutrient desert, microbial equilibrium, and aromatic integration resulting from refined structure. Wines cellared in this way display the “good Brett” soulfulness often reported but seldom understood by modern enologists. More about Integrated Brett Management (IBM)
Integrated Pest Management (IPM) Top
The promotion of natural ecological balance of flora and fauna in the vineyard. Beneficial insects such as praying mantis, Anagrus epos wasps, and ladybugs are utilized to control pest populations as an alternative to absolute control through the use of heavy tillage, pesticides and herbicides. The resulting living soil appears to impart mineral flavors, anti-oxidative vigor and longevity to the resulting wines. More about Integrated Pest Management (IPM)
Lees Top
Yeast sediment. Usually divided into gross lees and fine lees. Gross lees are the first to settle, and often contain harsh and bitter materials. Fine lees, which settle later, can be sweet and cream-like. Suspended lees can be injurious to young red wine by attacking unpolymerized anthocyanins through adsorption as well as enzymatic degradation, resulting in drier tannins. The yeast cells in lees break down over time, and after the wine’s polymeric structure is complete, these can coat the structure, rendering tannins softer, fatter and more available. This process is analogous to the conversion of dark chocolate to milk chocolate by incorporating milk protein. Lees incorporation into wines increases their reductive strength.
Living soil Top
By eschewing tillage, herbicides and pesticides as much as possible, the vineyardist can foster a healthy soil ecology. A healthy earthworm population is a good indicator of soil health. Living soil supports the growth of mycorrhizal fungi, which are thought to facilitate uptake of trace minerals. Wines grown on living soil tend to have enhanced mineral flavors in the finish, reductive strength and longevity. The pursuit of a living soil doctrine is an effective, practical approach to these ends which every grower can adopt because it does not require the extreme restrictions mandated by organic certification. More about Living Soil
Malolactic fermentation Top
A secondary fermentation undergone by most red wines and some whites by the action of bacteria similar to those responsible for transforming milk into buttermilk and yogurt. These bacteria consume the natural grape’s malic acid and convert it into the less acidic lactic acid, along with byproducts such as diacetyl, which is the artificial butter flavor used on movie popcorn. Malolactic diminishes wine’s freshness and fruitiness, lowers acid taste, and raises pH. These effects are minimized if malolactic completes during primary fermentation, and contact with yeast will absorb diacetyl. If by contrast malolactic fermentation is delayed until wine is barreled down, its action can soften oak tannins.
Maturity, red grape Top
From the grapevine’s point of view, true ripeness occurs at the completion of Cycle Two, at which point berries contain mature, viable seeds and optimum levels of color and flavor in order to attract birds. This point is characterized by cessation of sugar transport into berries and of malic acid respiration and by the commencement of field oxidation. Although past practice was to gauge maturity by monitoring sugar content (brix), The postmodern view advocates against this measure of maturity. Winemakers can assess maturity through berry inspection and sensory evaluation of juice, skins and seeds, as well as by analytical measures, particularly monomeric anthocyanin, polymeric pigment, and oxidative crosslinking. More about Maturity, red grape
Optimum maturity for winemaking is related to the desired style and the techniques to be employed in the cellar, particularly the desired longevity and the methods contemplated for resolving tannins. Optimum harvest time often does not correspond with desirable brix. Reverse osmosis is routinely employed to address excessive rain or sugar in berries.
Microbial equilibrium Top
The application of Integrated Pest Management techniques to the microbial ecology of the cellar. Controlled microbial competition is encouraged in order to stabilize wine prior to bottling so that sterile filtratration can be avoided. Cellar temperatures above 60oF and pH’s in the range of 3.6 to 3.85 are beneficial in promoting microbial balance. See Integrated Brett Management.
Minerality Top
A taste sensation characteristic of wines grown on limestone, shale, schyst or in living soil, which resembles the aftertaste of a half shell oyster or of a tiny electrical current in the throat. Minerality can be reproduced by the addition to conventional wine of very dilute tinctures of trace mineral dietary supplements. Wines with strong minerality generally possess more reductive strength than their conventional counterparts. More about Minerality
Microoxygenation Top
The invention of Patrick Ducournau, a vigneron in Madiran who in the early 1990’s sought a method to save the local variety tannat from extinction. Locals were attempting to globalize by replacing this highly tannic variety with more drinkable grapes such as merlot, so Patrick sought a method to tame the tannins, stumbling in the process upon a complete shift in understanding of wines true nature and leading to the postmodern school of wine élevage.
Patrick discovered that tannat had a huge appetite for oxygen, and if not exposed in youth to many times what a barrel’s skin could supply (about 1 ml of oxygen per liter of wine per month), would form dry tannins which would age poorly. The German introduction of stainless steel and inert gas, a boon for riesling, had thus undermined traditional vinification of reds, tannat being the most extreme example.
Working with Michel Moutounet, Director of the Faculty of Oenology at Montpelier, Patrick devised a system for precision oxygenation, metering in minute bubbles of pure oxygen and studying the effects. Treatment became divided into three phases. In Phase 1, red wines, depending on their tannins, could build structure and stabilize color at rates of 10 to 100 barrel equivalents (mls/L/mo.). Rather than becoming oxidized, they actually increase in reductive strength during this period. After malolactic and sulfite addition, Phase 2 preconditions the wine for barrel at 2 to 10 mls by refining structure and texture, balancing reductive vigor, and promoting aromatic integration. Phase 3 occurs post barrel, when some wines lack reductive strength to remain barrel but require final harmonization, for example from the raw tannins newly extracted from deep in wood where toasting cannot reach.
Recent competition from other companies selling oxygen dosers and diffusers but unwilling to teach the technique’s subtleties to winery clients has led to widespread misunderstanding about micro-oxygenation’s nature. Several vendors of oak alternatives promote the use of oxygen to replace barrels with tanks and to soften the harshness of poorly prepared oak products. Unlike its imitators, Ducournau’s company Oenodev has consistently stressed high performance equipment, intensive training, and a sophisticated understanding of élevage principles combined with labor-intensive attention to the wine.
Micro-oxygenation is employed throughout the world today to stabilize, enhance, balance, integrate and distinguish a wine’s true expression. This is essentially what the Aztecs taught the Belgians: the refining of cocoa powder into chocolate, through oxygenation (conching). The technique forces the winemaker into close and frequent interaction with the wine, during which issues of balance, timing, and purpose are constantly scrutinized. Its benefits for increasing quality and for acquainting winemakers with wine’s true nature far outweigh considerations of cost savings. While MOx can be utilized to soften and refine cheaper wines, its highest and best use is in to increase the flavor depth, soulfulness and longevity of the world’s top wines. More about Microoxygenation
Nanofiltration Top
Crossflow filtration in the range below ultrafiltration and above reverse osmosis, limited to the molecular weight range where monovalent ions can be separated from divalent, i.e. between 500 and 1,000 daltons. Since nanofiltration makes a separation in the middle of the wine flavor range, no applications of this type of filtration have been legalized in the U.S.. This term is erroneously applied to loose reverse osmosis applications below 150 daltons which strip more flavor than tight RO but can remove compounds which do not pass into tight RO permeate.
Nutrient desert Top
A key strategy of Integrated Brett Management which works in the vineyard to deliver harvested fruit with healthy nutrient levels so that a complete and thorough primary fermentation is possible without need for addition of chemical fertilizers. Wines containing in excess of 1.0 gm per liter of fermentable sugar are at risk for non-sterile bottling, but the consumption of micronutrients is equally important to creating a nutrient desert. More about Nutrient desert
Oxidation Top
The progressive deterioration of wine due to excessive exposure to oxygen over time. Late stages of oxidation may accompanied by loss of freshness in aromas, brown color, aldehydic or nutty aromas and coagulation of tannins into dry, grainy, dirty astringency and precipitated sediment. Paradoxically, early and skillful introduction of oxygen (micro-oxygenation) does not oxidize wine but rather increases reductive strength which inhibits oxidation and prolongs longevity. More about Oxidation
Oxidative polymerization Top
Certain types of phenolics (vicinyl diphenols, for you geeks) have the capability to form chains by consuming oxygen. Since the products of the reaction are more reactive than the original reactants, a cascade occurs in which young red wines consume oxygen at a rapid rate and use it to create a rich, light structure. Oxygen thus has the role of a wire whisk in a tannin soufflé. Monomeric anthocyanins are highly reactive with oxygen-activated tannins, and are readily incorporated into these chains. Since anthocyanins cannot themselves form polymers (they are not vicinyl diphenols), they terminate the polymer, like “book-ends.” The higher the anthocyanin content, the shorter the resulting polymeric pigment and the finer the texture. Oxidative polymerization results in hard tannins which can mature into high quality structure. More about Oxidative polymerization
Permeate Top
The filtrate passing through any crossflow (tangential flow) filtration.
Phenolic vigor Top
A broad class of organic compounds which contribute many of wine’s characteristics, including its color, texture and many of its flavors. For you chemistry nuts, a phenolic is simply any compound containing a benzene ring (six carbons in a ring connected by double bounds) with an –OH bonded to it. Red wine can be thought of as liquid chocolate, because its phenolics are almost identical, and because phenolics aren’t generally very soluble and exist in wine as tiny suspended beads called colloids.
Aside from many direct contributions to taste (especially bitterness) and aroma (especially from oak), phenolic structure influences aromatic integration of wine aromas and thus is the source of wine’s soulfulness. Phenolics are also a source of the reductive strength which protects wine during ageing.
Proper artisanal work with red wine requires a good balance of different phenolics such as tannins, anthocyanins and sometimes oak constituents. Heavily pressed wine fractions are sometimes blended into weak young wines to achieve phenolic balance. More about Phenolic vigor
Pigment, polymeric Top
Tannins and anthocyanins form into chains through oxidative or non-oxidative polymerization. Monomeric anthocyanins are vulnerable to attack by yeast enzymes, sulfite bleaching, precipitation and even oxygen itself, but polymeric pigment is stable and protected. Polymeric pigment forms colloids incorporating hundreds of chains. The longer the chains, the coarser the texture. The shorter the chains, the softer the wine and the greater its power for aromatic integration.
Postmodern winemaking Top
A philosophy developed in the 1990s in France which makes use of the benefits of 20th Century technological innovations, but also explores what was lost during the period when Scientific Enology sought to organize our knowledge of wine and perhaps let slip the ancient wine craftsman’s empirical expertise. In the eight millennia preceding the modern era, winemakers labored without the benefit of electricity, petrochemical herbicides and pesticides, or the theories of modern chemistry and microbiology. There were no sterile filters, inert gas, electric pumps, stainless steel tanks. There was no concept for yeast, for oxygen, for chemical preservatives. Wine was expected to be liquid poetry. Ben Franklin called it “proof that God loves us and desires us to be happy.” The Romans planted the vine all over Europe and harnessed its seductive power to stabilize an empire for a thousand years. Postmodern winemaking seeks to deliver once again this level of soulfulness. Our job is to steward our vineyards and perfect our cellar technique to bring forth the authentic expression of a distinctive terroir by crafting a refined structure which integrates its aromas into a single voice.
Reductive strength Top
This word has lots of other meanings, but in chemistry, reduction is simply the opposite of oxidation, and reductive strength is just a shorter way of saying anti-oxidative power or vigor. Reductive strength is measured as the rate at which a given wine can consume oxygen without a resulting buildup in dissolved oxygen (DO). Wine in a reduced state is closed in aroma and often produces sulfides, but these traits are not defects, since they indicate the wine’s ability to undergo prolonged ageing.
An important duty of the postmodern practitioner is to balance reductive strength, a complex task in which wine attributes must be matched with intended style, required longevity, and closure type. Stelvin closures, for example, do not dissipate reductive strength as readily as corks.
Anti-oxidative vigor derives from at least three sources: phenolic reactivity, lees stirring and mineral energy. Living soil practices promote mineral energy and flavors.
Phenolic reactivity can be promoted through balanced vines with a healthy Cycle Two, optimum maturity, and adequate extraction during fermentation. Excessive hangtime is particularly injurious to reductive strength, and three weeks beyond maturity can easily rob 90% of vigor and longevity. Paradoxically, micro-oxygenation can be employed in very young red wines to increase reductive strength and longevity. Later in development, reductive strength can be diminished through controlled use of oxygen.
Retentate Top
The portion of the feed wine which does not pass through a crossflow filter and instead is returned to the feed tank.
Reverse Osmosis Top
An extremely tight filtration originally developed for water purification with a wide variety of applications for achieving postmodern goals. Originally utilized in rainy areas to remove rainwater from musts and thus facilitate maturity in wet areas, its use is now widespread in dry areas to remove excessive alcohol, this facilitating harvest at proper maturity by uncoupling the picking decision from brix. In this application, RO permeate, which contains substantially no flavor or color, is distilled to remove high proof alcohol and then returned to the wine. Exact alcohol levels called “sweet spots” are routinely observed, and precise alcohol content within one tenth of a percent is critical to harmonious balance. Reverse osmosis can also facilitate microbial equilibrium in the cellar through its ability to correct volatile acidity which occasionally occurs during élevage.
Seven functions of oak Top
Apart from the physical benefits of barrels such as storage, slow oxygenation, settling and off-gassing, oak extractives supplement deficiencies in wines by providing five holistic functionalities and two sorts of flavorings. Proper choices of oak to suit a specific wine should account for its needs for copigmentation, anti-oxidative vigor, sweetness, framing and aromatic integration before considering the benefits of its curing aromatics and toasting aromatics contributions to flavor. Oak should not be considered as primarily a vehicle for aromatic enhancement without reference to the impact of a chosen wood on the wine as a whole. More about Oak
SoulfulnessTop
An inherent quality of an artistic product constituting a message, a vivid sharing transcending words, from an artist to an audience. It can be a cello performance, a cheese, a dance, a sauce or a wine that touches us profoundly. Soulful wines often contain diverse interblended conflicting elements such as earth, fruit and spice which intertwine and convey a feeling of profound depth which can be deeply moving for a receptive audience. While the essence of soulful wine is a deep connectedness, of feeling personally known and understood by another, this connectedness is also achievable alone through enlightened contemplation of everyday objects. The production of soulful wines requires deep personal attention which sets aside automatic, formulaic or cynical blending practices.
Structure Top
The physical nature of suspended colloids which contain substantially all the color and tannin of red wine. Structural finesse is a direct artifact of anthocyanin / tannin ratio and oxygen exposure. Skillful guidance of young red wine to achieve good structure is called “élevage.”
Red wine is not a chemical solution, but derives its flavor properties from its colloidal properties. Indeed, wine’s deviation from “ideal” solution behavior is a good working measure of quality. Good structure alters the aromatic characteristics of wines by sequestering aromatic compounds so that sensory thresholds are not obeyed. Well-structured wines can contain many times the supposed threshold of pyrazines (bell pepper), guaicols (oak char) and ethyl phenols (Brettanomyces) without objectionable aromatic characteristics. This phenomenon is referred to as aromatic integration. Red wines deprived of oxygen in their development or exposed to excessive hang time will make coarse colloids which readily precipitate and lack aromatically integrative properties.
NOTE: There are many English-speaking connoisseurs, critics and Masters of Wine who employ this term in a very different way. Their use does not address any physical arrangement in the wine itself, but rather an aesthetic mapping of the elements of balance, such as acidity, sugar, bitterness, astringency, and alcohol which work together in a pleasing and balanced manner. To them, a wine with good structure is one in which the elements together create a focused and harmonious whole as might the characters in a well-spun narrative or musical composition. The French oenologues with whom I have worked use the term structure in my physical sense as described above (indeed, that’s where I learned it), and I suspect that like the terms grappe (bunch) and raisin (grape), Anglos long ago simply misapprehended their French acquaintances and gave birth to an English usage that differs in its particulars. I will argue for the utility and predominance of my more literal usage, in which the structure exists in the wine itself and not as a human aesthetic theoretical construct. More about Structure
Sulfides Top
Stinky compound reminiscent of rotten eggs, diesel, onions, canned asparagus or wet wool. Sunlight should never be permitted to shine on a bottle of white wine, as a very short exposure can lead to sulfide production in the bottle.
Sulfide production by yeasts occurs for many reasons and is not always indicative of difficulties. The degree of sulfides is important to assess. Small amounts of sulfides will occur in healthy fermentations as consumption during fermentation creates a nutrient desert. Proteins are broken down to constituent amino acids to provide materials for biosynthesis of essential micronutrients. After fermentation, reductive strength from proper red grape maturity or from mineral energy will lead to sulfide production in barrel and even in the bottle. It is the winemaker’s task, through proper oxygen regimen, to balance this reductive strength against the intention for ageability. Small amounts of sulfides in wines intended for ageing are a positive sign which knowledgeable collectors will applaud. Such wines consumed in their youth will benefit from aerative decanting. More about Sulfides
Sulfites Top
A class of preservative compounds (unrelated to sulfides) added to wine in the form of sulphur dioxide to control microbial and oxidative spoilage.
Wine made without sulfides is the highest achievement of a skilled postmodern practitioner and can result in wine of great terroir expression, similar to the production of unpasteurized cheese. Most wines need sulfites. Certified organic wine is not permitted the use of sulfites, which accounts for its inconsistency. More about Sulfites
Sweetness Top
One of the seven functions of oak identified in the postmodern system. For wines possessing angularity and framing but which lack a rich core of fruit, sweet oak is a tool for achieving flavor balance. Untoasted wood (coconut) and moderate toasting (vanilla) are useful for this purpose.
Tangential flow filtration Top
See Crossflow filtration.
Tannin Top
The source of structure and texture in red wine. Tannin precursors, notably flavonoid skin extractives, can undergo carefully guided oxidative polymerization or if neglected on the vine or in the cellar, will polymerize spontaneously into less desirable forms. Tannins interact with salivary protein to form precipitates in the mouth which exhibit a variety of sensory impressions, different forms of astringency or harshness. Postmodern winemaking uses English names for these impressions which honor the terminology established by French tradition.
Very young red wine always has grainy astringency (thought to be composed of copigmentation colloids) which we refer to as “green” tannin, not to be confused with underripe or vegetal characteristics. If never allowed exposure to oxygen, these tannins migrate during ageing into the rest of the mouth, eventually transforming into “dry” tannins, which leave a coarse, grainy impression all over the tongue and cheeks and interfere with other taste impressions. Dry tannin is the only type of tannin perceived under the tongue in the back of the mouth. It is the result of overly polymerized tannin, and its aggressivity should not be taken as a call to age the wine. Dry tannin is unstable and prone to precipitate, hence a marker signifying poor ageing potential. Dry tannin can also be present in young wines if produced from grapes left too long on the vine.
In balanced young red wines, early and careful exposure to oxygen leads quickly transforms green tannin into an aggressive, sheet-like, grippy “hard” tannin which is perceived entirely on the top of the tongue, covering the whole palate back to the throat. This type of tannic aggressivity is a good sign, and such wines will improve with age.
Our picture of the chemistry of this rapid transformation has only recently begun to emerge. When the monomeric flavonoids extracted during fermentation into copigmentation colloids are assisted to oxidatively polymerize, their sensory effects are radically altered within a few days. This process may be assisted prior to malolactic through Phase I micro-oxygenation. Surprisingly, this transformation is accompanied by an increase in reductive strength, which results in a temporary closing of the aromas but also increases the prospects for longevity.
As hard tannins evolve in the presence of oxygen, they diminish their grip on the upper palate (“firm tannin”) and begin to “melt” from the back palate forward. Tannins in this intermediate stage, melted in back and firm in front, are called “round.” Such wines show they have additional ageing potential and are on the right path to tannin resolution to “melted” (sometimes also called “soft,” “plush,” or “velvet” tannins) as they reach maturity. Melted tannins exhibit great aromatic integration and are generally quite stable. Properly resolved tannins are not a sign of imminent demise or poor longevity. Harmonious wines are capable of palatability in youth without sacrificing ageworthiness.
Oak tannins are perceived as a finely grained “parching/numbing” astringency on the top of the tongue in front but back from the tip. They contain the anesthetic eugenol, which causes a numbing hollowness in this region, surrounded by fine, parching aggressivity. Because of their position on the tongue, oak tannins are easily confused with firmness or roundness.
Threshold Top
A term from modern sensory science which denotes the minimum aroma or taste intensity at which 50% of a group of subjects are able to detect or recognize a specific compound. At low levels, subjects are able to pick out a spiked sample as different, but cannot identify the difference, and thus both detection and recognition thresholds are spoken of. For example, the recognition threshold for the sweetness of glucose in water is around 0.5%, but subtle flavor changes result at much lower concentrations. In aroma work, gaseous concentrations are much more difficult to measure than concentrations in solutions. Accordingly, aroma thresholds are generally expressed as solution concentrations. Insidiously hidden in this way of speaking is the assumption that aroma volatility coefficients are similar among wines. This has led to much consternation in explaining the differences in sensory assessment related to both recognition and quality judgment in wines containing Brettanomyces-related notes. For wines with vegetal pyrazines, alterations in structure using micro-oxygenation lead to large, consistent and predictable alterations in threshold while having no effect on composition, clear proof of non-ideal solution behavior.
Ultrafiltration Top
A family of crossflow filtrations used to move tannins within the winery rather than buying artificial phenolics from non-wine sources. It replaces fining and does not strip flavor. Nothing is wasted, and there are no effluents to dispose of. UF operates in the 1,000 to 250,000 dalton range, thus tighter than sterile filtration and considerably looser than reverse osmosis. While the former seeks to remove only suspended solids including yeast and bacteria, and the latter seeks to retain all but tiny molecules such as water, ethanol and acetic acid, UF separates dissolved solids from the suspended colloids that comprise tannin structure. It is useful for removal of browning and reduction of tannin to soften press wines without the volume and flavor losses of conventional fining with proteins such as egg white, gelatin, casein and isinglass.
UF byproducts include Xpress and cofactor concentrate. XPRESS is a concentrated tannin retentate which can be added in tiny amounts to wines lacking in structure. Late in the concentration stage, small compounds which comprise the glue that holds phenolic colloids together permeate through the UF filter in concentrated form. Added in small quantities to deficient red wine fermentations, this cofactor concentrate material aids extraction of color and flavor.
Veraison Top
The transition of red grapes into Cycle Two during maturation marked by the emergence of red anthocyanin color. More about Veraison
Vineyard Enology Top
Distinct from viticulture, a winemaking presence in the vineyard is necessary to ensure that harvested grapes are well-imbued with the building blocks of good wine structure, health, and character. We seek to present the distinctive terroir expression of each unique vineyard setting through enhancement of soil ecology, vine balance and careful maturity assessment. Through skillful artisanship in the cellar with an eye to structural finesse, we can optimize aromatic integration, harmonious balance, anti-oxidative vigor, and graceful longevity if and only if vineyard enology has met its goals. More about Vineyard Enology
Xpress Top
The concentrated retentate of an ultrafiltration of heavy press wine. Xpress may be added when fresh in very small amounts to improve the structure and aromatic integration properties of weak red wines. Micro-oxygenation may be desirable to refine the structure of resulting wines.