In a previous article, we have reviewed what was governing the value of wine, and therefore why should a natural wine find a place in our economies. We defined natural wines as green wines and the new green as transparent. So not only do we have now to define what really is a natural wine, but to explain why – and how – it is transparent. Is this because, to find their place among an ocean of over branded products, they have to fit their best digital dress to seduce a virtual audience, loosing their genuine and magnificent contingency ? Or is their “transparency” a contrario the actual result of their essence?

Since “organic” and “biodynamic” wines are produced from organically or biodynamically grown grapes, natural wines, not only are made from organically or biodynamically grown grapes, but also in the most natural possible way in the cellar. This by far, is not obvious with conventional wines in which you can put a lot of “additives” when in the cellar to correct almost all wine’s attributes, even if made with organic grapes(1). These additives considerably influence acidity, stabilization, mouth-feel factors such as tannins and flavours. And some winemakers are monitoring these elements chemically and technologically on an industrial scale, so they are in a position where they literally build a wine from -almost- scratch (i.e. erasing any climate influence and variations on grapes and wine quality coming from the vintage, or soil deficiency). Moreover, they most of the time completely sterilise the soils, slavering them to clinical death for years by killing almost every living organisms and kicking down biological cycles.

An important step to note in the right direction is that the current EU law has recently evolved and the definition of “bio wine” has finally emerged after years of struggle, but is still quite permissive and for instance allows SO2 levels that are far above what a natural wine maker would accept. The new EU law, voted in March 2012, in force from August 2012, is an addition to the bio vine growing process certification. The winemaker will have to be already certified as a bio vine grower and show the european bio logo as well as the official certification body and mention “bio wine” on the bottle. But while new EU rules confine SO2 usage to 100mg/litre, 150 mg/litre and 370 mg/litre for red, dry white and sweet wines respectively (2), with some organic and biodynamic certifying bodies being a little more stringent, natural wines rules are the stictest of all, with most producers allowing under 30 mg SO2/litre for reds, 40 mg/litre for whites and 80 mg/litre for sweet wines, with some growers allowing none at all. This just to talk about SO2.

But this is only figures. And natural wines stand far beyond figures, on the vertical paths of philosophy. Especially when this philosophy has been existing from before humanity was even able to write or read. Especially when this philosophy is leading to purity and honesty of expression. As Pierre Jancou, a famous French natural wines specialist, says: «It might be a Grand Cru Burgundy or a Vin de Table, a pure pinot noir or a blend of ten different cépages, and might cost £5 or £5ooo, […] natural wines taste of the grapes from which they are made and the place where they have grown». A terroir can’t be built or relocated, it just has to be respected and understood. And some winemakers, through biodynamic, express their terroir at their best. Natural wines therefore are the direct and pure expression of their terroir, something unique, by definition.

As Nicolas Joly from La Coulée de Serrant and “La Renaissance des Appellations” once said :« to achieve zero technology in the cellar, you need to be an artist in the vineyard». This ability to transcript and pass through their wines such a synthesis of uncountable factors, the mix of which being different every year, makes the wine grower an incomparable and invaluable intelligence of nature. Natural wines transparency is the result of this. A genuine and simple expression of life complexity, orchestrated by human intelligence. Because of this genuine quality, natural wines are a major reference to understand how to build sustainable value with respect to – and the help of – the environment.  And this transparency has a taste: the Garden of Eden’s one.

(1) list of  additives and processes allowed by EU law :

acidity correction:
Depending on what the winemaker wants the wine to taste like, acidity can be rectified by either raising (warmer climate) or altering it (cooler climate). Acidity is an essential attribute in wine, defining its structure and balance. Too much or too little acidity have major impact on its tasting perception and ageing behaviour. Properly grown grapes contain balanced tartaric, malic and citric acids. Their quantity lowers as grapes ripen, so time of picking is a key decision for the vine grower. Deciding to harvest earlier will preserve more natural acidity , while picking grapes later  allows more fruit maturity and more potential alcohol, with a reduced acidity. Acids commonly used for acidification: tartaric acid, malic acid, citric acid or a blend of all three. Additives commonly used for de-acification: Calcium carbonate, potassium carbonate or bicarbonate.

fining agents (stabilization):
Fining is the process where a substance (fining agent) is added to the wine to create a chemical reaction with the suspended particles, producing larger molecules and larger particles that will precipitate out of the wine . Fining can remove soluble substances such as polymerized tannins, coloring phenols and proteins; some of these proteins can cause haziness in wines exposed to high temperatures after bottling. The reduction of tannin can reduce astringency in red wines intended for early drinking. Many substances are used as fining agents but there are two general types of fining agents — organic compounds and solid/mineral materials. Since fining is common, there is the risk of valuable aromatic molecules being precipitated out along with the less desirable matter. Some producers of premium wine avoid fining, or delay it in order to leach more flavour and aroma from the phenols before they are removed. Nonetheless, fining is reckoned less harsh than filtration, with its advocates believing that it better mimics the natural clarification and stabilization process. Other stabilization processes like ageing or fermentation in oak barrels will form protein complexes with the oak tannins and precipitate out the undesirable particles. Protein fining is commonly used to remove excess of tannins associated with astringency and bitterness. Here are the different types of fining agents for winemaking:calcium bentonite, carbon filtrationcasein, colloidal silicon dioxideegg albumin, gelatine, isinglass (sturgeon bladder), polyvinylpolypyrrolidone (PVPP, E1202)

tannins (mouth-feel and ageing):
Tannin is the substance in wine that creates an astringent, dry mouth feel. Tannins occur naturally in grape skins and stems, as well as in many other plants. The amount of tannin naturally occurring in wine depends on the grape skin’s thickness and time of the must’s exposure to the skins. Since some grapes have thin skins and white wines are not fermented with grape skins at all, tannins are lacking in many wines. Because of this, tannin powder can be added to the must at the start of fermentation to add a drier mouth feel to the finished wine. Tannins are a polymer (similar molecules join together to form a chain) of either a flavonoid or non-flavanoid phenol. Young wines are mostly composed with dimeric (chain of 2) or trimeric (chain of 3) tannins, but these polymerise (join together) to form chains of up to 8 or 14 units when wines are ageing and substantially modify the flavours development. Tannins can be monitored through many ways during the wine making process: addition of stems to the crush, extended maceration periods, harder pressing, maturation in oak barrel and other various new practises. Wine makers usually add powdered tannins in warmer regions but also in cooler climates like Burgundy. Oenological tannins come from a variety of sources including oak (both American and European, toasted and untoasted), chestnut, grapes (both skins and seeds), exotic woods (such as tara and quebracho) and gall nuts. Tannin addition usually happen early on in the vinification process. There are many reasons why tannins may be added, and a vast array of different products are available on the market for specific purposes such as to reduce the perception of astringency or bitterness, modify mouthfeel, fix colour or ‘correcting’ raisined or sun-damaged fruits. A subject of great current interest is microoxygenation, which has had a remarkably high take-up worldwide over the last decade considering that there are so far few experimental data backing up the claims of manufacturers of microxygenation devices and service providers who offer this technique to winemakers. It’s likely that oxygen applied at the right time and in the right quantities can have a beneficial effect on the mouthfeel and structure of red wines, but as yet there’s no clear evidence as to the sorts of tannin modifications that are taking place. It seems that microoxygenation is an important tool in tannin management, but winemakers currently have to ‘fly blind’, relying on guesswork and frequent tasting to judge when enough is enough for the particular wine they are working with.

For more info about winemaking processes, please see this useful and very well documented link.

(2) IFOAM EU Information on SOresidues in organic wine