Wednesday, May 24, 2017

A summary of the various dry white wine styles

In this series I examined the winemaker's challenge in navigating between the twin evils of reduction and oxidation in the construction of white wines; both faults but both having desirable characteristics as you move further away from the edges. The below chart illustrates the dry white wine styles that have been covered in this series. Below the chart are short descriptors of each of the styles along with links to the posts in which they are detailed.

According to Lukacs' research (Inventing Wine), modern wine did not arise until the advent of the relevant scientific and technological advances of the Enlightenment. Prior to that period, wine drinkers consumed oxidized, sour wines that were "fortified" with all manner of additives designed to either slow its decay or make it more "palatable." Lukacs points out that winemaking in the first half of the 20th century was a reprise of thousands of years past -- "a process of letting nature run its course."

But, beginning in the 1950s and 1960s, grape growers and winemakers began to employ new tools to attain specific "stylistic and qualitative ends." On the technical side, the introduction of temperature control and regular chemical analysis allowed greater control over the fermentation and this gave greater impetus to the concept that humans "could and should assume control" of the winemaking process.

Based on Clark Smith's interpretation of the history of that period, the "tools of 20th century winemaking" were stainless steel, inert gas, refrigeration, and sterile filtration (a product of nuclear energy) and this "modern winemaking revolution exploded out of Germany" in the form of Rieslings that were fresh, sterile-filtered, and completely without oxidative characters. According to Smith: "the idea of a light, sweet, fresh, fruity wine like Blue Nun was as world changing as color television." 

These tools and techniques allowed the introduction and use of a reductive style of winemaking. The essence of reductive winemaking is the production of wine without the presence of oxygen. Grapes are harvested from cool regions and the juice is fermented cold in closed stainless steel tanks. Juice is protected, as is the wine, through maturation and bottling. This method is particularly beneficial for grape varieties such as Sauvignon Blanc, Petit Manseng, Chenin Blanc, and Gewurtztraminer that are rich in varietal aromas that can be placed at risk in the face of oxidizing effects.

In the case of hyperoxidation, the deliberate introduction of oxygen into the juice causes enzymatic oxidation of the phenols. The process entails adding large amounts of oxygen to the juice, allowing it to settle, and then racking it from the brown precipitate just prior to fermentation. This oxidation will cause browning of the juice but the phenols will have been polymerized and will precipitate out.

Skin-contact white wines are recognized by a combination of their residence on the early part of the orange color spectrum, their earthy flavors, and enhanced mouthfeel. These characteristics are the result of macerating the skin of crushed and de-stemmed white grapes in their own juice (i) prior to pressing and (ii) under controlled time and temperature conditions.

White juice fermented on their skins are differentiated from skin-contact wines both on the basis of time -- skin contact wines are macerated for between 2 and 24 hours while the fermented-on-skin wine is macerated for weeks to months -- and phase within the production process -- skin contact is a pre-fermentation process while its compatriot extends beyond that to fermentation and, in many cases, maturation. These skin-fermented wines, more commonly known as "orange" wines, can be further broken down into two broad classes: traditional and contemporary.

With all of the advantages associated with stainless steel fermentation, oak had to have some overriding benefits for winemakers to continue using it as a fermentation vehicle. And it did. According to Ibern-Gomez, et al*., "Fermentation in oak barrels leads to wines with much more complex sensory properties, largely attributed to the phenols extracted from oak wood." Further, wine is aged in wooden barrels to: (i) enhance its flavor, aroma, and complexity through transfer of substances from the wood to the wine; and (ii) allow gradual oxidation of the wine.

The premature oxidation issue in white Burgundies has been identified by both Jancis Robinson and and Jon Bonne as the engine driving the change in Burgundy from 'buttery,' 'rich,' and 'toasty' Chardonnays to wines that are now characterized by (Jancis):
  • High levels of acidity
  • No trace of the toastiness of obvious oak
  • Leanness on the palate
  • The tell-tale flinty smell of recently struck matches.
I have named this style of winemaking oxo-reductive.

The final style-specific installment in my discourse on white wine styles was the non-ouillé (evaporative loss during aging not topped up) Savagnin wines of the Jura. These oxidatively styled wines are unique to both the region and the cultivar.

©Wine -- Mise en abyme

No comments:

Post a Comment