Why are wines becoming more alcoholic?

Lang Wines Background: Too much alcohol? In recent years an ongoing discussion has developed regarding the apparently increasing alcohol content in wine. There are strong views on both sides of the debate; some wine writers and critics prefer the recent trend towards bigger, higher alcohol "fruit-forward" wines and others hold to the more traditional and relatively more delicate food-friendly wines.

Alcohol in wine is a natural product of fermentation. Sugar in grapes is converted into alcohol and carbon dioxide by yeasts; as grapes ripen, the weight of the sugar in the grape increases; the grapes become sweeter. The measure of sugar in grapes is ‘degrees Brix,’ the percentage by weight of the sugar in the juice. The higher the Brix at harvest, the greater will be the weight of sugar in the fermenting must and the higher will be the alcohol in the finished wine. The conversion factor of sugar into alcohol is approximately 0.6, i.e., multiplying the degrees Brix (percentage sugar) by 0.6 will approximate the alcohol content by volume in the finished wine. For example, winegrapes harvested at 22 degrees Brix, fermented ‘dry,’ (no sugar remaining), will result in a wine of 13.2% alcohol (22 X 0.6=13.2). For a wine to reach a 14.9% alcohol level now more frequently seen on wine labels, a harvest sugar of 25 Brix must be attained (25 X 0.6=15%).

Until recently, throughout its thousands of years long history, wine has been made using a ‘grandfatherly’ approach; winemakers made wine the way their fathers and grandfathers made wine. In France this tradition became codified into law. Their Appellation d’Origine Controlee (AOC) system regulates and controls virtually all aspects of French viticulture and enology. Entrepreneurial innovation and experimentation were suppressed by decree to protect and maintain a conformance to what was once a superior status quo. However, as Emerson said, “A foolish consistency is the hobgoblin of little minds.” As a defensive protection, the AOC was as rigid as the Maginot Line and just as effective. While the French comfortably basked in what became a false sense of superior permanence, the new world in Australia, South Africa and California began to experiment, innovate, evolve and improve in both the vineyard and winery.

Changing Times: The avuncular "...little old winemaker" of 1960s advertising was being replaced by University trained enologists, pro-active viticulturalists and modern technology. Appreciation of wine in the United States and elsewhere began to transcend the market offerings of ‘red burgundy’ and ‘Chablis;’ the maturing post-war generation of ‘baby-boomers,’ introduced to imports of Mateus and Lancer’s Crackling Rose in college, entered the work-force and began demanding wines of increased quality; they were willing to pay more for wines made from varietals by wineries utilizing more sophisticated winemaking techniques.

Lang Wines The historical marker for the beginning of that transition is the founding of the Robert Mondavi Winery in the Napa Valley. By the 1970s, evolution had accelerated into revolution. While changes in European viticulture and winemaking were restricted or even prohibited by AOC constraints, in California and other ‘New World’ regions, a synergistic science-based partnership began forming between grape growers, winemakers and academic research. In the winery, impossible to clean concrete and wooden open fermenters were replaced with temperature-controlled hygienic stainless-steel tanks; variable wild yeasts were suppressed in favor of selected yeasts with known, desired properties and fermentation effects; many recently developed specialty yeasts have a higher tolerance to the alcohol they produce and remain productive in higher alcohol fermentation conditions. Pumps, hoses and all winery equipment is now hygienically clean, made of stainless steel, glass, food-grade plastics and other inert materials. Advances in filtration, chemical analysis and sterile bottling rooms have reduced the need to ‘sulfur’ or otherwise treat the wines for preservation. Many potential wine ‘faults’ have been virtually eliminated by clean technology. A consumer can still buy a wine that he doesn't like, but it has become increasingly rare to buy a wine that has spoiled.

Vineyard Contributions: The wine we drink is grown in the vineyard. Advances in proactively managing vineyards have greatly increased vine-health and thereby grape quality. World-wide viticultural research and experimentation in the last fifty years has led to improvements in varietal cultivars, rootstocks, vineyard siting, and all vineyard cultural practices. Clone selection has developed desirable berry and cluster sizes to optimize skin to juice ratios. Vine spacing and precisely monitored and controlled drip irrigation systems, combined with inventive trellis systems for canopy control and leaf removal enable grower to exert far greater control and influence over variables that affect wine quality and flavors. Actively managed and properly sited healthy vineyards permit the extended maturities that result in higher sugar levels (brix) while maintaining desirable acid balance. Watch for greatly increased use of drones to monitor all aspects of vineyard health and performance.

Wine Quality: The successful application of research and science in the winery & vineyard has permitted the art of winemaking to flourish. Whereas in the past, much winemaking talent was expended dealing with faults, negative variables of wild yeasts, non-sterile conditions & less than perfect fruit, today’s winemaker, in those wineries & regions that have adopted the advances in knowledge, technology and vineyard cultural practices, can concentrate his or her art and talents on making the best possible wines from the best possible fruit. The impact of this revolution in technology and knowledge on wine quality has been extraordinary.

A major by-product of this broad-based quality advance in winemaking is the general increase in maturity of the winegrapes at harvest. In past years the ‘desired brix’ for most red wines was generally in the 23 brix (percent sugar by weight) range which when fermented ‘dry’ (no residual sugar), would result in a finished wine with an alcohol of 13.8% by volume. The federal tax on wine is increased for wines above 14% alcohol, so there was also some motivation for wineries keep their wines below that threshold. However, as the CPI and wine prices have risen over the years, the wine-tax has remained constant and the relative tax expense for wines exceeding 14% alcohol has decreased.

Lang Wines Increasing Brix: Approaching harvest, degrees Brix (percent sugar) can be increased in two ways. Sugar is added to the grapes on healthy vines as a natural process during ripening; proactively employing modern viticultural techniques has had a significant effect on vine health and productivity. Extended "hang-tine" can naturally add sugar to the grape. However, Brix will also rise if the grapes lose weight due to moisture evaporation or translocation; late season hot weather can desiccate the leaves and grapes on vines that have expended their seasonal energy and access to water; this reduces the water content in the grapes by evaporation and is evidenced by shrivel or raisining grapes. Because the water (juice) in the grape is lost, the weight of the cluster is reduced. Since the weight of the sugar remains constant in the now lighter cluster, the degrees Brix will increase; raisins are sweeter than grapes. In the past, overripe grapes would begin to shrivel or raisin or even sunburn in late season hot spells, resulting in flavors described negatively as "overripe," "raisiny," "pruny" or Porty."

Acid levels would also decrease and the pH of the juice would rise, all conditions on the negative side of the desirable qualities ledger. Many premium vineyards, planted with carefully chosen clones and incorporating advanced cultural practices, now produce fully-mature ripe grapes that attain 25-degrees brix or more at harvest without shrivel or raisining. They produce wines with alcohol approaching or even exceeding 15%; some refer to these wines as "fruit-bombs." However, extended maturity at many vineyards can now be attained while maintaining good acid ratios and appropriate pH levels; although not overripe or flabby, wines from these balanced high maturity grapes also provide more intense flavors, often characterized as ‘fruit-forward’ wines. Extended the hang time also increases the risk of crop damage from early rains.

Conclusion: Yes, "too much alcohol" will "...drown the flavors," but so will too much oak or too much acidity, or too much of any single wine component. However, within the range of alcohol in the great majority of the wines we consume, i.e., between 12.9% & 14.9% alcohol by volume, the actual alcohol difference between a 14.9% "high" alcohol wine & a "lower alcohol" wine of 13.9% is actually very minimal, equal to perhaps only 0.25 ounces of alcohol, the amount found in only an additional two (2) ounces of the lower alcohol wine. The sometimes passionate debate regarding alcohol levels in wine will continue for many more vintages and may never be resolved.

Bob Lang
Lang Wines

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