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    • Oenology
  • 2015

"Reflections on the elaboration of noble wine and the production of natural wine".

“Reflections on the elaboration of noble wine and the production of natural wine”.

PREAMBLE

The cultivation of grapes in wine-growing areas and the production of wine from them are the product of thousands of years of experience:

  1. The transformation of fresh grapes into wine is a spontaneous phenomenon requiring only intelligent supervision and judicious handling on the part of man, to the exclusion of any artifice akin to fabrication. Comments: This point is fundamental; it introduces the idea of naturalness and makes it more precise, rightly excluding the notion of fabrication. It is said that freshly picked grapes left in a container will fall prey to yeast. They transform the solid grape into a liquid. In both cases, the fruit of this transposition will be pleasant to consume, the major balance of bitter and acidic impressions having been transposed from grape to wine. Through these transformations, man assists and guides this birth.
  2. As such, even the most ordinary wine is not just a fermented beverage, but much more a biological medium, possessing the factors of its internal equilibrium and the microbiological and biochemical elements to guide its evolution. Comments: We must insist on the notion of biological medium, i.e. life. Like each of us, it will be born, grow and die. We’ll know it as a newborn, a youngster, an adult, an old man, and perhaps even as an expression of wisdom, if its birth permits. It’s the elements of his “body” that will evolve.
  3. Under well-defined ecological conditions, certain wines are capable of achieving an exceptional originality resulting from a multitude of as yet unknown factors. The natural character of wine affirmed in this way down the ages is a civilizational value that must be preserved, both for the scientific field of investigation it represents and to preserve it from sophistication and devaluation. Comments: Here, the idea of the environment comes into play once again; the fact that the vine grows in siliceous, clayey or chalky soil… whether it’s on a slope or flat… will shape the expression of the wine, stylizing it. Thus, natural wine is based on three notions: spontaneity, life and environment. It’s hardly surprising, then, that a civilization has accompanied this beverage, whose rhythm of life can be compared to that of man.

RECOMMENDATIONS

  1. Experience has shown that the quality of the finished wine is closely dependent on the quality of the grapes harvested. Research into the factors contributing to this quality must therefore begin at the viticultural stage, and not only in subsequent handling. Comments: We want to emphasize prevention: we don’t cure, we prevent. To achieve this, we need to follow the wine’s production in toto, from the vine to the consumer’s glass. Any error in the choice of grape varieties, vineyard management, plot location or vinification will have an impact on the wine’s expression.

THE RAISIN

  1. Grape quality in the production phase must be considered from two angles: intrinsic and technological. This means that the grape must have its own composition adapted to its performance. The grape has the following structure: skin, pulp, pips, brush, pedicel, with an average grape composition. White wine, like rosé, is made solely from the pulp, i.e. the juice, also known as “must”. Red wine is made from the whole fruit. The technological aspect must be adapted to the grape and not the other way around. All too often, we take into account the grape’s suitability for harvesting and transport, without considering the final product.)
  2. Intrinsic quality derives from the environment itself: it is mainly the result of the choice of grape varieties, including rootstocks, adapted to each production region. Comments: The idea here is to say that, depending on soil type, the engine, i.e. the vine, will be chosen; the environment imposes the “tool of expression”.
  3. Technological quality is the result of human intervention; it derives from all the production processes which, for a given grape variety, give it maximum substantial value. Comments: This is the work of man. Depending on his knowledge, he chooses the grape variety or varieties best suited to the environment, and then, taking this into account, in particular the climate, he helps the plant to develop by protecting it from crop pests.

These production processes consist of :

  • positive practices, in particular the selection of healthy varieties and strains, and cultivation methods;
  • preventive practices designed to protect vines and their fruit from damage caused by animal or plant parasites.
  1. In the search for the technological quality factors listed in the previous paragraph.

a) As far as cultivation methods are concerned, every effort should be made:

For floors :

  • maintain all the geophysical conditions of the microclimates, and develop practices designed to safeguard the natural vegetation environment, in particular by avoiding the drying out of soils and the destruction of their microflora;
  • encourage the maintenance and growth of humus and other growing conditions that naturally limit parasitism. It’s worth remembering that the vine, a permanent monoculture grown for thousands of years, is therefore more exposed than any other to the depletion and degeneration of its environment. Comment: soil elements are responsible for the main characteristics of wines: silica gives finesse, limestone body, clay firmness, excess humus “common”. If we wish to understand the expression of sincere “small” or “great” wines, a reflection of the places where they are produced, we need to be aware of these influences. Similarly, excess humidity increases the acidity of the wine, while cooling the earth, water bodies, forests and hedges, balancing air masses and protecting against prevailing winds, mark the character of wines.
  • Tampering with any one of these factors can alter the composition of the wine, and therefore its expression. Wine-growing sites must therefore be protected. Soil maintenance, whether mechanical or, in exceptional cases, chemical, must respect the quality and quantity of the soil’s microflora.)

For grapes:

  • Through planting density, pruning, and the choice and dosage of fertilizers, we aim for productivity that preserves the maximum specific characteristics of the grape, expressed in particular in red grape varieties by the “solids/liquid phase” ratio, without ignoring the need for profitability. Excessive mineralization, which raises the pH of the environment, and turgidity, which dilutes the constituents, are detrimental to the grapes’ technological quality. Comments: Depending on the region, there are between 4,000 and 12,000 vines per hectare. Not so long ago (a century ago), vines in Europe were planted in “mixed” densities of up to 20,000 vines/hectare. The introduction of animal traction created rows of vines to facilitate the passage of farming implements. Planting density depends on soil type and depth, and therefore on rooting potential. In poor, siliceous soils, planting densities will be low; in richer soils, where the root system develops, densities will be high. A high density also limits the plant’s root development, and therefore its aerial system, thereby regulating the vine’s load, i.e. its production.
  • Too high a load “dilutes” the grape, making it poorer. Among other factors influencing grape composition, man is responsible for pruning. After a great deal of experimentation, he succeeded in guiding his vine stock to produce a well-balanced grape that could be transformed into wine. Left to its own devices, the vine is a creeper. If left unpruned, it would produce a large number of impoverished grapes. A trellis that has already been pruned will produce a large number of bunches of grapes capable of yielding 6° alcohol. A well-managed vine to produce an 11° wine should be planted at 10,000 vines/hectare and pruned short, producing just a few bunches. To make the transition from table grapes to wine, it is therefore necessary to prune the vine in order to limit the number of bunches, thus concentrating on this small number the plant elements produced through photosynthesis. Pruning methods vary according to the region in which they are grown: Guyot, gobelet, etc. The nature of the soil and the distribution of the climate have inspired them. Pruning is a real “mode of conduct”, not a fantasy.
  • Fertilization – By providing the plant with an unsuitable soil solution, man can hinder its development and alter the characteristics of the wine. Today, the use of fertilizers must be guided by the results of soil analyses. Excessive fertilization leads to overgrown vegetation, which is responsible for the “common” character of wines. It also leads to imbalances in the soil that are detrimental to the plant (blockage, leaching of mineral elements, etc.).
  • Liquid/solid phase ratio. An interesting argument. Once again, wine grapes are opposed to “fruit grapes”. The latter will seek to attract the eye – large berries, for example – enabling a more voluminous presence on the palate. For wine, it’s the other way around. The substances responsible for aromas and color are fixed to the grape skin. The larger the grape, the smaller the ratio of skin to flesh. Aromatic potential is therefore reduced. This is a form of dilution. For a given grape variety and terroir, therefore, grain size should never be increased, either through the selection of plant material or through vineyard management.)

b) In the field of active prevention of parasitism, it is important to avoid the escalation of radically destructive treatment processes for a given parasite, which, through “biological imbalance”, leads to the recrudescence of other forms of parasitism. In this respect, viticulture should pay particular attention to the biological resources of integrated pest management.

It’s also important to avoid the use of susceptible treatments:

– to leave toxic residues on the grapes;

– alter the microflora;

– adversely affect its constitution by increasing berry volume or reducing skin constituents. In any case, it is essential that any residues (or their metabolites) from treatment of the grapes are fully metabolized or eliminated during vinification, without reducing or altering the hygienic value of the wine.

Comments: Everything that lives needs protection from its enemies. Vines, like other shrubs, are beset by microscopic fungi such as mildew, powdery mildew and grey rot, or insects such as leafhoppers, red and yellow spiders, cochylis, etc. Man must intervene to ensure the harvest. But the reason why we encourage people to avoid escalation is that, all too often, treatments are carried out out of habit, rather than on the basis of the real dangers associated with the conditions that favor the hatching and spread of these plant pests. Relying on integrated pest management is at least one way to avoid overloading the environment with synthetic molecules.

WINEMAKING

  1. At the end of the cultivation phase, the search for optimal grape maturity is the most important factor for rational winemaking. Optimum ripeness does not necessarily mean maximum ripeness or over-ripeness. Broadly speaking, in terms of saccharin richness and acidity, it is defined as the state of the grapes that is most likely to avoid the correction of musts, and to give a defined margin of composition to the wine. (In hot climates, this optimum state of ripeness is often exceeded, resulting in numerous winemaking difficulties: excessive alcoholic richness, insufficient acidity, fermentation overheating, wine deterioration, etc.).

Conunentaires: Optimum ripeness: Why do we insist on this aspect? Everything in wine is in balance: acid, astringent, sweet, burning, tactile elements… all bounce off each other to achieve balance and sensory coherence. If the soil is responsible for the wine’s style each year, the climate will modulate its silhouette. This is the case in most wine-producing countries, with the exception of Greece, where the climatic distribution is very similar from one year to the next. The vintage thus introduces two ideas: one about the age of the product and the other about its climatic silhouette.

  1. At harvest time, harvesting and transport procedures must deliver an intact raw material to the winemaker, so that he can vary the handling, selection and sorting of the grapes, as well as their possible use as whole harvests.

Comments: The grapes must be transported intact to the winery. There, depending on its condition and nature, it will be fermented after receiving appropriate care and handling.

  1. In winemaking, particularly at grape reception, it is important to use the most direct and simple forms of handling, always giving preference to those that avoid dilaceration of the stalks, brutal trituration of the skins and excessive aeration of the musts. This recommendation also applies to the devatting and pressing phases for red wines.

Comments: If the grapes were crushed in the vineyard, enzymatic and microbiological phenomena would alter the harvest. The introduction of mechanical harvesting is a concern for oenology. It is therefore necessary, throughout all the phases of grape processing, to avoid brutal actions responsible for bruising or tearing plant tissues).

  1. As a system for treating the harvest, winemaking processes should aim to safeguard the biological quality of the environment and provide the winemaker with control over it. Physical processes are preferred to chemical treatments, whenever they can achieve equivalent or improved results. The production of special wines (naturally sweet wines, yellow wines, sparkling wines, etc.) is unquestionably similar to natural methods when it consists of judiciously directing the particular evolution of these types of wines without any artifice akin to manufacturing.

Comments: In white grapes, we must also insist on the need to extract the juice from the grapes, removing only the pulp and not the juice from the solid parts of the bunch. It is important to avoid the introduction of foreign chemical compounds, and to prefer physical processes. This recommendation is complementary to the previous one.

  1. Any changes in must composition during the winemaking process should only be considered as corrective or palliative measures when the year’s climatic conditions have caused the harvest to be insufficiently constituted, unstable or unusual. These corrections should be carried out within the technological limits strictly necessary for correct winemaking conditions. Setting them up as a constant and systematic practice would constitute an abuse and a denaturing of the wine. On the other hand, only correction additives that are fully metabolized, integrated or eliminated by fermentation are acceptable. For this reason, it is generally preferable to correct the harvest beforehand, rather than the wine afterwards.

Comments: When climates vary greatly from one year to the next, we may need to correct either a lack of acidity or sugar, or an excess of both. In most people’s minds, it’s the correction of a “lack of sugar” that is most familiar. The idea of correction in the face of climatic conditions has nothing to do with the evolution known as enrichment, a practice that is reprehensible because, in this case, we are enriching a material impoverished by production errors. It’s the difference between helping a plant in difficulty in a gloomy climate and formalizing a lax attitude of which the authors have nothing to be proud of. We insist on the need for these corrective additives to be fully metabolized. This is important. If sugar is added, it is entirely transformed; on the other hand, the addition of concentrated must is a kind of coupage, since this concentrated must brings not only the sugar but also the other elements of the grape.

  1. Among these corrective measures, CHAPTALIZATION, among others, is by no means a necessity, even in regions where it is constantly used. Ancient documents attest to the fact that, in the past, part of the nutritional and hygienic value of local wines was due to their low alcohol content, and that the majority of European grands crus acquired their fame with a significantly lower alcoholic strength than today. It has been proven that moderate chaptalization, limited to less than 2° enrichment, brings a definite improvement to wines obtained when the natural saccharine richness of the must is below the usual average. On the other hand, the escalation in alcoholic strength that is tending to become part of winemaking practices is a serious aberration that must be denounced, as it unbalances the constitution of wines, encourages alcoholism and feeds the propaganda of wine detractors. Comments: Chaptalization takes its name from CHAPTAL, who was the first to advocate the practice. There is a limit to any correction, and the one recommended (2°) is far from satisfactory. Excessive chaptalization penalizes the producer, as the wine acquires a burnt taste character and its aromatic expression is greatly attenuated. Allowing wine to be sold by degree is a serious mistake, as it has led to the gradual creation of alcoholic vineyards. But it’s not just sugar or concentrated must that can produce alcohol; grape varieties themselves can be responsible for the exaggerated presence of alcohol. We urgently need to stop accepting alcohol content as the criterion for wine’s value. Everyone is concerned, from the producer to the consumer. We need to return to an appreciation of wine on the basis of all its constituents, of which there are now more than 500.
  2. The duration of vinification, the way it is carried out, and the physico-chemical parameters to be applied are all inspired by the primary concern of extracting from the raw material the maximum intrinsic qualities it can give, combined with the highest natural capacity for resistance to alteration. The empirical practices of past centuries have already channeled this research within limits that it is important not to ignore. However, in the various wine-growing regions of the world, it is not certain that established, or even ancestral or reputedly traditional, practices have always yielded the best qualitative benefits that can be expected from this type of production. The production of table wines in particular, even if it calls on more powerful means, should not be dissociated from that of wines of origin, nor should it be directed towards the industrialization of anonymous products. This class of wine, consumed daily on a vast scale, requires particular vigilance in terms of hygiene and food value. The overcoming of routine, the more enlightened and methodical resources of technology, and the education of consumers through worldwide exchanges, still open the way to the improvement of many productions. Comments: Winemaking is a microbiological operation. The main phenomenon is alcoholic fermentation. Several breeds of yeast are involved in transforming grape sugar into alcohol. This is the main result. However, as the liquid phase changes from sugar to alcohol, substances contained in the red grapes dissolve, enriching the medium with polyphenols and aromatic substances in particular. At this stage of the wine-making process, since we are dealing with a microbiological act, it is necessary to control one factor: temperature. We must insist on the need to equip all wineries with thermal equipment to cool or heat, depending on the country, the grapes or their fermenting juice. The application of this knowledge is still a long way off. It is therefore certain that wine, if the conditions under which grapes are produced are not tainted by errors, will tend towards an increasingly sincere expression.

WINE STORAGE AND DELIVERY

  1. The storage phase for bulk wine after vinification represents the time needed for it to evolve before being released for consumption. This phase is inspired above all by the desire to preserve the wine’s initial qualities and not to compromise its evolution, by protecting it against the deterioration to which it is naturally subject. For table wines and vins de primeur, this phase is reduced to the time needed to clarify the wine. For ageing wines, it involves a maturation period that is a matter of use and experience.

Comments: When the wine is made, it has a more or less cloudy appearance and the sensory characteristics of a young wine, marked, for example, by a dominant bite or astringency. First, the wine is freed of suspended particles, mainly yeast and bacterial corpses, and small fragments of plant matter from the solid parts of the grape. The wine then clears, and the deposit – known as lees – settles to the bottom of the vessels. Racking, or decanting, separates the clear wine from its lees. In a second phase, the wine’s insoluble constituents, such as potassium bitartrate (or gravel) and colorants, are separated, giving the wine optical stability and eliminating certain “sharp” sensory characteristics. For many red wines with ageing potential, further stripping is required. They will be brought into contact with a precious auxiliary: oak wood. The size of the vessels – barrels or barriques – and the contact time vary according to the wines and their vintages. This phase is known as “wine ageing”. It’s an important and delicate process. It must enhance the wine’s expression without detracting from its originality.)

  1. In the field of table wines and primeur wines, early marketing is a practice to be encouraged for all types of product favored in their youth by original primary aromas, but unsuitable for aging. In some cases, premature bottling of these wines before natural physico-chemical stability has been reached requires special stabilization treatments prior to bottling. In these cases, as in the case of winemaking, physical processes are preferred to chemical treatments for equal effectiveness.

Comments: Wines offer us three main stages of expression: primary, secondary and tertiary aromas. The last two phases are acquired in the bottle. The bouquet is a complex expression of the wine after a more or less long maturation in bottle, i.e. in a reductive medium; these impressions are marked only by the origin due to the terroir, the grape variety having faded before the imprint of the environment. Most table wines, as well as the original primeur wines, are sought after for their primary impressions, as their suitability for this slow maturation in bottle is not one of their properties. In order to bring the wine to bottling, it is advisable not to rush anything; the wine must “follow its life”, and man should only help it in this process by avoiding any introduction of exogenous substances.

  1. Any kind of treatment should be limited to the effectiveness necessary for the presumed consumption time of the wine. It is important that the quest for microbiological or chemical stability does not degenerate into an escalation of forced safety: asepsis is to be preferred to antisepsis, and ambient conditioning to chemical sterilization. Delivering wines that are devitalized or polluted with additives that are foreign to their own constitution is a disservice to the cause of the wine.

Comments: This paragraph complements the previous one. It emphasizes the notion of care as opposed to treatment. Consumers also play a role here. By criticizing the presence of small deposits in wine, they have in many cases forced the professional to go too far in stripping wines to prevent them from ending up in the bottle. Knowing the wine, understanding it, being aware of its evolving and therefore unstable state, of its sensitivity to cold and heat, should make it possible to excuse a few visual defects that are easily eliminated at the moment of serving by the graceful gesture of decanting.

  1. As far as ageing wines are concerned, storage methods should aim to achieve natural chemical and microbiological stability. As far as possible, the production of wines whose transformation processes have not been fully completed, and which therefore require forced conservation procedures, should be avoided. Furthermore, treatments aimed at preventing oxidation, ensuring microbial stability or maintaining limpidity should preferably be carried out using neutral physical processes or natural products that can be eliminated without residue.

Comments: The finality of wine takes on even greater force here. The role of man in ensuring that processes run smoothly is recalled. Air contact is the enemy of wine, apart from a few special wines such as sherry or Jura vin jaune. Wetting, i.e. keeping containers full, is an essential practice in wine maturing. The recent use of inert gases in oenology to avoid contact with air is a famous achievement. This avoids the abusive use of sulfur dioxide.

  1. For all types of wine production, technological research should focus on developing the study of environmental conditions in wine, with a view to eliminating or inactivating instability factors by the most natural means, rather than neutralizing them through artificial means. (Comments: It is the product in its environment that dictates the care to be given to the wine. We need to move away from the idea of a technological wine with a common character).
  2. On the other hand, public education should be geared towards giving primacy to the substantial, gustatory and hygienic qualities of wines, rather than to factors of appearance, such as clarity or stabilization obtained to the detriment of the preceding qualities. We should not be afraid to assert that wine, provided it has retained the characteristics of a biological environment, is subject to EVOLUTION, and that a slight modification of its appearance, without altering its characteristics, is less harmful than any treatment aimed at blocking this evolution. Comments: Helping the public to learn about wine is a necessary task. Reminding them of the role and importance of tasting, and showing them that this analytical approach is within their reach, are part of the actions that need to be taken. We must never forget that the purpose of wine is to be drunk, and therefore to give sensory pleasure without causing health problems, and obviously without abuse. Learning to discover a wine in its youth, to follow it through its still closed secondary expressions, and finally, after many years, to feel that long-awaited bouquet, that impressive language of the vine, is a work full of humanism.
  1. Without ignoring the economic necessities which compel wine-producing countries to authorize the use of additives for preservation and stabilization, the Académie Internationale du Vin expresses the wish that all wines with defined hygienic qualities, obtained through natural processes, be brought to the attention of the public. Comments: Every wine has its own physiological effects. This diversity of wines cannot be over-emphasized, as it prevents addiction and hence abuse. There is a real need to help every wine-producing country to present genuine wines. Since no two environments are alike, each wine will retain its own style, never competing with its neighbor, but complementing its partners.