I’ve been thinking about what drives changes in wine styles—consumer demand, winemaker experimentation, the influence of critics and writers, some combination of these?
Take for instance the popularity of high-alcohol Napa Cabernet and Chardonnay beginning in the mid 1980’s. In the 1970’s the best producers in Napa seemed intent on emulating French wine styles. Alcohol levels were typically around 12.5% and apparently Napa wines tasted similar to French wine. In the famous Judgment of Paris tasting in 1976, many of the judges mistakenly identified the California wines as French. Yet, by the late 1980’s, Napa wines were exhibiting increasing alcohol and fruit ripeness.
What is the explanation of the change? Global warming likely doesn’t explain the dramatic explosion in fruit ripeness over the course of just a few years.
One explanation might be that consumers wanted these riper styles. The mid-1980’s saw a substantial increase in wine consumption in the U.S. including many novice drinkers who tend to prefer the sweeter, smoother wines made from riper grapes. But I doubt these novice drinkers were drinking premium Cabernet or Chardonnay. Low priced budget wines would not have had high alcohol since wines above 14% would have been taxed at a higher rate and technology for removing alcohol did not yet exist. In general, I think consumers respond to and reinforce trends; they don’t create them.
Of course, on this issue of ripeness and high alcohol, the influence of the wine critic Robert Parker is relevant. Parker famously preferred rich, ripe wines and criticized the complacent, old-school winemaking that he thought still had too much influence in France. Parker started his newsletter in 1978. But he was not particularly well known until 1982 when he attracted attention as the only critic proclaiming the substantial virtues of that vintage in France. As consumers embraced his 100 pt. scoring system, winemakers began to make wines aimed at garnering high scores leading to rich, sumptuous, powerful wines that would dominate the market for decades.
But many of the wine making reforms advocated by Parker—riper fruit, lower yields, better sorting, and more new French oak—had already been advocated by Emile Peynaud, the influential French oenologist who used his position at the University of Bordeaux to promote what came to be known as the International Style, essentially wines with the qualities endorsed by Parker. The impetus toward riper fruit was already in the works before Parker came on the scene.
Also during the late 1980’s, phylloxera was discovered in Napa, and many wineries replanted with new rootstock and clones that produced sugar more easily. New trellising systems were put in place that brought more sunlight to the grapes and modern yeasts were developed that were more efficient at converting sugar to alcohol.
There is a certain logic to ripeness especially for California that in the end might explain this massive shift in wine styles. If California could compete with Bordeaux and Burgundy by producing ripe fruit more consistently, why not go even further with what California does well? Unlike Bordeaux and Burgundy, Napa has lots of sun in summer extending well into the fall. Sun is California’s competitive advantage. Why not make it their signature? In other words, if you’re looking to capture a variation that sets you apart from your competition, for California, ripeness is the path of least resistance.
No doubt Parker had a great deal of influence, but I think a larger factor was a natural evolution, a tendency built into wine grape growing in California that winemakers captured and advanced.
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While I agree with your final conclusion, i.e., critics influenced winemaking but it was also an evolution brought on by consumer preference and viticultural changes, I feel compelled to clarify a couple of statements you made. First, higher alcohol wines did not begin in the ’80s. They began in the ’90s. In fact, the ’80s were known as the “food-wine” decade in which the pendulum swung far in the direction of lean, high acid wines that supposedly were more food friendly. The riper style of the 90s was due in part to a rejection of these “food” wines.
Secondly, I have analyzed enough older wines to know all those 12.5% statements on labels are pretty much meaningless. Vintners put 12.5% because that was the midpoint for 11 to 14%, a tax class. Labeling law dictates you can be +/- 1.5% when under 14% as long as you don’t label it over 14% or under 11%. 12.5% was convenient.
Finally, your comment about modern yeasts being more efficient in producing alcohol is not true. Yeasts have not become alchemists, discovering a way to produce more alcohol from a gram of sugar than is chemically possible. Decades ago the OIV adopted .594 as the standard conversion factor for grams of sugar to ethanol. Louis Pasteur suggested a conversion of .61 in the late 1800s. While certain strains of yeasts have been found that shunt some of the carbon down other metabolic pathways, resulting in a lower sugar to ethanol conversion, no strain has been found that can magically make more alcohol than Pasteur’s proposed maximum.
Michael,
Thanks for your informative comment. I wasn’t drinking much wine in the 1980’s so I have little first hand experience with that decade. When I was poking around looking for data on alcohol levels in the 1980’s I found contradictory reports. But most of what I was reading seemed to suggest alcohol levels were creeping up by the end of the decade. So I went with the late 1980’s. Parker was by that time well known and listened to. I entirely agree about the flux in alcohol statements on labels. But without a personal hydrometer that’s all we have to go by. And I didn’t intend to say certain yeasts produce more alcohol. I was pointing out that modern yeasts were more efficient, converting sugar more quickly with fewer stuck or troublesome fermentations. In theory, at least, that should lead overall to higher alcohol since getting to dry happens more often.