Tiptoeing Around the Perception of Alcoholic Warmth in Domestic Pinot Noir

I have been wrestling of late with the issue of perceived warmth or even heat in domestic Pinot Noir. I believe this perception should be a component of a tasting note. I find that many reviewers, including those writing in the major wine magazine publications, either fail to comment about perception of alcohol in Pinot Noir wine reviews or downplay its importance. Alan Meadows in the Burghound, is a notable exception.

Whether to report the awareness of alcohol (alcohol content in wine is mainly ethyl alcohol, next in importance to water) in a wine is a matter of degree. A subtle warmth is often present on the finish of domestic Pinot Noirs when the alcohol percentage (ABV) is 14.2% and above. This is certainly acceptable and not considered a flaw. However, if the wine finishes with perceived heat or even lip burn, the wine is considered alcoholic, out of balance and flawed, and should be appropriately downgraded. Supertasters are more sensitive to alcoholic heat and may be more likely to report even a mild sensation of warmth (I am not a supertaster).

Beyond the undesirability of the sense of alcohol in wine, there are a number of negative outcomes of high alcohol. If the alcohol is high relative to acidity and astringency (riper grapes have lower acidity and higher pH levels), the wine will taste excessively soft, heavy and flabby. Alcohol, being highly volatile, will negate the enchanting aromas and palate of Pinot Noir, especially as the wine warms in the glass. A study published in the scientific journal PLOS One (“What Can the Brain Teach Us about Winemaking? An fMRI Study of Alcohol Level Preferences,” March 18, 2015) used MRI imaging to compare reactions of human subjects to matched pairs of red wines of high- and low-alcohol content. Significantly greater activation in the brain regions responsible for flavor processing and food reward was found for low-alcohol wines in comparison to high-alcohol content wines. The authors concluded that low-alcohol wine induced greater “attentional exploration of aromas and flavors.”

The higher the alcohol, the less the chance the wine will be balanced. The ABV in wine never changes over time in the bottle, so if a wine is high proof, the sense of alcohol will increase over time as the wine ages and the fruit dissipates. Higher alcohol wines imply advanced ripeness of grapes at harvest, and this increases the risk of Brettanomyces and bacterial-induced volatile acidity (VA) during vinification. Wines with significantly elevated ABV simply do not compliment food, and raise the specter of undesirable health consequences from potentially excessive alcohol consumption.

I have always considered it important to incorporate the ABV of a wine in a tasting note, and, I believe I was the first wine writer to do this many years ago. That said, the absolute ABV is not as important to the taster as the sensory experience. It matters little that a wine is 13.0% ABV or 14.9% ABV if the wine is perceived as hot.

I have also attempted to incorporate available harvest Brix data in my reviews. Brix is the relative density of dissolved sucrose in unfermented grape juice. If all the sugar in grapes is fermented, the sugar to alcohol potential strength is as follows: Brix 21.5º = ABV of 12.1%, Brix 22.5º = ABV of 13.0%, Brix 23.7º = ABV 13.6%, Brix 24.8º = ABV of 14.3%, and Brix 25.8º = ABV of 15.1%. Variations may occur if water additions or alcohol-lowering equipment is employed, both unlikely with domestic premium Pinot Noir producers.

Recently reported before publication pioneering work by Australian scientists at the Australian Wine Research Institute has led to the discovery of yeast strains that preserve the flavor of fine wine at lower alcohol levels. Certain yeast strains (non-Saccharomyces strains) were shown to produce a 1.8% ethyl alcohol reduction in both Shiraz and Chardonnay wines. This is exciting research that could greatly benefit the wine industry.

A very informative article appeared in 2011 in the Journal of Wine Economics (“Too Much of a Good Thing? Causes and Consequences of Increases in Sugar Content of California Wine Grapes”). Probably most wine enthusiasts were unaware of this review, and since it has relevance to this discussion, I will summarize the important points in the article.

The authors begin with the premise that the sugar content of California wine grapes has increased significantly over the past 10-20 years, implying a corresponding increase in the alcohol content of wine made with those grapes. They cite data that show that the sugar content of California wine grapes at harvest increased from 21.4º Brix in 1980 (average across all wines and all regions) to 21.8º Brix in 1990 and 23.3º Brix in 2008. This amounts to an increase of almost 7 percent over the most recent 18 years and 9 percent over 28 years. Since sugar converts directly into alcohol, this indicates that a corresponding 9 percent increase in the average alcohol content of wine occurred. This change could be attributed to a number of factors but change in climate was not as significant a variable in this study as the demand for more intense or riper-flavored wines, the so-called “Parker effect,” which resulted in longer hang times.

When data from the Liquor Control Board of Ontario was examined, it was found that label claims systematically understated the alcohol content of California wine and this was thought to result from a perception that higher alcohol content diminishes the consumer value of certain wines. A 1% margin of error is permissible in wines with an ABV above 14.1% such that wines with a labeled ABV of 14.1% may actually be anywhere from 14.2% to 15.1%. The fact that so many California Pinot Noirs have a 14.1% ABV on the label supports the notion that wineries fudge a bit to avoid the undesirable perception of higher alcohol content.

I looked at the average of reported ABV of California Pinot Noirs reviewed in the PinotFile from six recent vintages, 2008-2013. There were several interesting observations.

1 Average ABV range was relatively consistent for each vintage except 2011 when this cool vintage showed a noticeable drop in average ABV, especially for cooler regions such as Anderson Valley, Sta. Rita Hills, Sonoma Coast and Santa Cruz Mountains.

2 Over this six year period, there was not an escalation of ABV in any region. This indicates that California Pinot Noir, at least over the most recent six vintages, did not show the increase in average ABV that has been reported for all red wines as a group in California.

3 Santa Lucia Highlands Pinot Noirs had a significantly higher average ABV in every vintage.

4 Marin County and Santa Cruz Mountains had the lowest average ABV in every vintage (tied with Sonoma Coast in 2011).

5 The Russian River Valley and Santa Lucia Highlands, both warmer Pinot Noir growing regions, showed a more consistent average ABV over the six vintages than the other cooler regions.