Pinot Gris or Pinot Grigio

Which is better: Pinot Gris or Pinot Grigio? The grape variety is the same in both, just going by different names in different countries. But, there are substantial differences in aroma and flavor. Pinot Gris/Grigio does reflect a “sense of place”, a manifestation of the terroir in which it is grown.

The grape variety is widely dispersed throughout Europe’s winegrowing areas. In Germany, it is called Ruländer. In Burgundy it’s Pinot Beurot. Alsace used to call it Tokay d’Alsace, but that has been discontinued in favor of Pinot Gris.

Who cares whether American wineries call it Pinot Gris or Pinot Grigio? For a long time, Oregon’s strict label law mandated that the variety be labeled as Pinot Gris, even though wineries in the State’s southwestern Rogue and Umpqua Valleys wanted to call it Pinot Grigio. The reality in America is that the largest market for this wine, by far, is full-service Italian restaurants. And, they have a clear-cut preference that the wine be bottled in a Bordeaux-shaped, flint colored (clear) bottle, and labeled as Pinot Grigio, regardless of its aromatic and taste characteristics.

Origin of the grape

The grape variety apparently began in Burgundy, then was spread all over Europe by the Cistercian monks in the 12th Century. It is a color mutation of Pinot Noir, and scientists say the two are genetically indistinguishable. Clusters are a little larger than Pinot Noir, and the berry size is larger. The color generally is pink to mahogany. In some areas, a deep purple blush develops on the south side of the grapes.

Virtually all Pinot Gris/Pinot Grigio planted in America’s west coast states after 1987 is Colmar 46 and Colmar 52 clones. They were propagated from cuttings imported through Oregon State University by the efforts of OSU’s Drs. David Heatherbell and Porter Lombard, David Adelsheim, and Oregon winemakers’ close relationship with Alsace producers. Plantings that predate 1987 are an unknown clone, because they were propagated from Alsacien plant material smuggled into Oregon in the suitcase of one of the Oregon industry’s pioneers. Hence, they are referred to as “the suitcase clone.”

Where are the best ones made?

Let’s start with where the wines are made. The world standard of Pinot Gris quality is made in Alsace, France. Grown there, the wine is full-bodied, rich, complex, and tends to have relatively high alcohol content, around 12.5-14 percent. Some reviewers say the wine is “oily,” although I find that attribute difficult to define. Perhaps they mean that the wine has a thickness, or viscosity, like olive oil. The high alcohol can contribute to this tactile sensation. So, too, can the glycerol produced by the long, slow ripening period.  Pinot Gris often has a steely, or racy, edge to it, although the pH can be relatively high and the titratable acidity low. This feature must have something to do with the balance between tartaric and malic acids, as well as an unusually high citric acid content.

Flavors can be: green apple, pear, peach, apricot, fig, coconut, vanilla, anise, fennel, melon, lemon, lime, mineral, flint, and honey. Wildflowers can be present in the aroma along with the faint smell of the fruit esters responsible for the flavors. Frequently, the same terpene found in White Riesling lends pungency. Some have a discernible earthiness. In Alsace, identifiable oak flavors (woody, vanilla, smoke, etc.) are considered to be a flaw, and those wines are denied use of the vineyard’s appellation on the label.

To use a musical analogy, many of the best Pinots Gris have a purity and focus of flavor, highlighted by a citrusy character, that plays like a clear high note.

Most European Pinot Grigio is made in northeast Italy’s Friuli region, although some excellent examples are grown in the northerly Alto Adige region around Bolzano. Many wine-producing regions make unspectacular Pinot Grigio. The vines tend to be cropped heavily and the climate is warmer than in Alsace. Most Pinot Grigios I’ve tasted do not deliver the attributes usually given the wines by promotional literature. Typically, Fruili Pinot Grigios are lower in alcohol, 10.5-11.5 percent, lighter bodied, simpler and fruitier than those made in Alsace. Flavors include: green apple, peach and almond, frequently with a slightly bitter finish. There is a tendency for the wine to be thinner and perceived as “hot”, even though the alcohol level is not high.

So, what causes these differences? Let’s explore two factors that make up a large part of terroir: heat summation (temperature) and solar radiation (light). These are the two factors that drive photosynthesis in the grape leavers, the engine room for everything that ends up in the wine.

Selected Pinot Gris-Grigio Sites

Example Vineyards:

Four producing areas have been chosen to illustrate the differences. They are:

Alsace, FR – Gloeckelberg vineyard, acknowledged to be one of the best vineyards in Alsace. It is located ten miles north-northwest of Colmar, the Alsace wine capital, rising to the north above the tiny village of Rodern. The southeast slopes are 1,050-1,180 feet elevation. Soils are coarse sandstone and clay over dense granite. St. Hippolyte is the nearest town of some reputation. Another famous vineyard is nearby: Domaine Trimbach’s Clos Ste. Hune, within the Grand Cru Rosacker appellation. But, alas, Ste. Hune contains no Pinot Gris. Annual rainfall is relatively low, especially in the fall, as the area is within the rain shadow of the Vosges Mountains.

Alto-Adige, IT, Abbazia do Novacella – Alto Adige is where Santa Margherita Pinot Grigio, by far the most popular Pinot Grigio marketed in America, is grown. But, we have something better. The mountainside village of Varna, northeast of Bolzano, produces Pinot Grigio on a par with those of Cormons. Many say better. On this slope is the 12th Century Augustinian  Abbazia di Novacella, an abbey with a seminary, convent, boarding school, and relatively large winery. The wines support everything, just like it was during the Middle Ages in most of Europe. Soils are alluvial clay and gravel (glacier-deposited) over Dolomitic limestone. The elevations vary from 1,969 to 2,461 feet on a south-southwest-facing slope.

Friuli-Venezia-Giulia, IT, Cormons – The areas of Collio Goriziano and Colli Orientale del Fruili are generally among the best quality producers in the Friuli area. The hillside village of Cormons, within Collio Goriziano and twenty miles southeast of Udine near the Slovenian border, is selected. The terraced vineyards above the town yield some of the best Pinot Grigos in Friuli. The Southwest-facing slope varies in elevation around 325-670 feet. Soils are calcium-rich marl and sandstone.

Friuli, IT, Environs – The vineyards on the outskirts of Udine, the region’s dominant city, are chosen to represent the ocean of common Pinot Grigios in Italy. It is a broadly open basin from the north coast of the Adriatic Sea and framed by mountains to the east, north and west. The soils are alluvial from glaciers that once flowed down from Austria and Slovenia: clay, sand and gravel. Elevations run around 380 feet MSL.

Heat summation

The photosynthetic activity resulting from temperature energy is generally measured by heat summation. Simply, the indicator is the day’s average temperature over 50°F, summed from April 1 through October 31. For example, assume a day which has a high temperature of 80°F and a nighttime low of 60°F. The average daily temperature is 70°, (80° + 60°)/2, and that day’s contribution to degree-days is 20° (70°– 50°).

Heat summation has some weaknesses as an indicator of total photosynthesis. The most important is that it represents only one of the two factors that drive photosynthesis. The other is that most weather stations are at airports or in highly populated urban areas. This circumstance is becoming more prominent with time, because many rural weather stations have been closing, further skewing the compilation of temperature trends toward higher readings. Temperatures recorded in urban areas are elevated compared with nearby outlying rural areas by a phenomenon called urban heat island (UHI) effect. UHI results from: the heat generated by building heating and cooling systems; heat given off by concentrated vehicular traffic; and heat stored in paved areas and building roofs during the day, then radiated out at night. Airports also have UHIs, owing to their extensive paving and aviation engine exhaust, particularly on takeoffs. Figure 2 illustrates the relationships.

Urban Heat Island

Vineyards are not located in UHIs. Further, they are virtually all sited at higher elevations than the weather stations. Therefore, adjustments have to be made for the UHI effect and altitude differences, as well as the proximity to large bodies of water (cooling), and to reflect heat energy moved from one place to another by prevailing wind patterns.

Heat summations for the four selected sites are shown in Table 1. Attention is directed to the far right column, the estimated degree-days for each site. Note how Gloekelberg and Varna are around 1,900-2,000 degree-days. Cormons is estimated at 2,277 degree-days. Udine Environs stands out at 2,869 degree-days.

Heat Summation Adjustments

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To further illustrate heat summation patterns for the selected sites, Figures 3 and 4 plot the average monthly degree-days during the growing season. Figure 3 is the monthly sequence; Figure 4 accumulates the cumulative amounts as the season progresses.

The monthly distributions for Varna and Cormons are fairly symetrical, with Cormons higher than Varna. Udine Environs is markedly warmer than both, owning to its lower elevation.

The curve for Gloekelberg is significantly later in the season, i.e., skewed to the right. Therefore, the fruit develops later there, and undergoes final ripening when the temperature is cooler. Final ripening is the time when the fruit flavors and aromas develop in the grapes.

Monthly Degree Days

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We often hear about the long, warm, sunny autumns in Alsace. These curves document the reason why the wine benefits from the phenomenon.

The cumulative heat summation curves depicted in Figure 4 do a good job of showing us what these seasonal profiles do for the timing of harvest. It is not possible to infer that perfect ripeness occurs at a common accumulation of degree-days for every location because other factors come into play. Among them is the phenomenon that the vine’s leaves cease photosynthetic activity when the temperature exceeds 95°F and transpires water in order to survive by evaporative cooling. The tipping point varies slightly from one variety to another, but 95°F is typical.

Cumulative Degree DaysBut, we can infer some generalizations. For example, Gloekelberg (Alsace) develops more slowly than the Italian site.

The heat units for Udine Environs are substantially warmer than the other three sites, bringing a much earlier harvest when the temperature is warmer. Thus, the grapes are hustled through final ripening too rapidly to develop the same complexity of flavors. The elaboration of compounds causing aromas and flavors is more complete the longer it takes for final ripening.

Solar radiation

The review of heat summation does not cover the whole environment analysis of the causes for grape flavor development. The other is light energy, or solar radiation. As mentioned earlier, both factors drive photosynthesis. How important is each, relatively speaking? Results of light box tests  done at UC-Davis in the 1960s provides evidence that light energy is about 30% more important to the photosynthetic rate than is temperature, especially for the range of conditions in which we find most vineyards.. For example, an increase of 5% in photons of light energy produces 30% more carbon dioxide respiration, the measure of photosynthesis, than a 5% increase in temperature. (See the citation of Table Wines” in the “Sources Consulted” listing. Incremental analyses of the curves for the two variables were performed by the author.) Conversion of the light energy from photons to watt-hours/sq.meter/hour was necessary to utilize currently available data for solar radiation.

Fortunately, the European Union sponsors a website,, which provides a large amount of solar data for use in solar panel design. Their database, heavily-based on satellite imagery as well as “ground truth” stations, permits access to data, recorded and estimated, for any set of map coordinates, i.e., latitude and longitude. Therefore, it is possible to get data for specific vineyard locations, regardless of proximity to weather stations.

Direct solar radiation is also known as beam radiation, direct solar irradiance and direct solar insolation.

Solar radiation data for the five vineyard sites are presented in Table 2. Values are for horizontal flat plate collectors, in Kilowatt-hours/m2, summed for April through October:

Horizontal Flat Plate

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Direct solar radiation measured by a horizontal flat plate collector is a calculated figure. The flat plate measures radiation in all forms as they impinge on a horizontal flat plate collector. The term for this measure is “global”. Global includes direct, diffuse and reflected forms. Diffuse radiation is measured by a separate sensor and deducted from global, then the direct, or beam, radiation is calculated from the remainder by trigonometry.

Monthly Direct Solar Radiation

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Were it not for several factors, the amount of direct radiation would reach its apogee on June 21, the summer solstice, when the sun reaches its furthest northern position relative to earth. Only Rodern and Cormons show this feature in Figure 5. Udine Environs and Varna do not because of high cloudiness in June.

The solar curves reflect the fact that solar radiation decreases as latitude increases, or moves further to the north.

Cumulative Direct Solar Radiation

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We see a different seasonal pattern for solar radiation than we did for heat summation. The curve for Gloekelberg is not shifted to the right as was temperature. That means solar energy contributes less to photosynthesis in the fall months than was true for temperature. This is a factor that further slows the ripening of the Alsace vineyard during final ripening.

The data for Gloekelberg shows an unusually low amount of radiation during the month of July. This is not an anomaly or data error. Alsace experiences an abnormally large amount of cloudiness in July. These are multi-year averages.

In like manner, Varna receives lower-than-expected radiation in June.

Cormons receives more radiation than Udine Environs during the middle of the season because its higher elevation keeps it above cloud cover in the valley.


This brief analysis does not produce statistically significant proof of the relationship between climate factors and wine quality. The attribution of quality was trusted to reputable wine writers. The sample size is very small.

No, the examples were chosen as representative of what is achievable in Pinot Gris/Grigio quality for each of the regions. Funny thing about vineyards and climate conditions . . . If one vineyard produces a certain quality and other characteristics, chances are most of its neighbors produce similar wines, given capable winemaking.

I think this exercise illustrates the difference between Alsace and Italian Pinot Grigio sites: a longer growing season with cooler temperatures during final ripening yields a much more complex and concentrated wine. It also makes the case for correlating quality with heat and solar radiation. But then, we already knew that, didn’t we? Wines are at their best when the grapes are grown in a marginal climate that brings the fruit to acceptable ripeness in most years.

Sources consulted

  • General Viticulture; A.J. Winkler, J.A. Cook, W.M. Kliewer and L.A. Lider; University of California Press; Berkeley, CA. Revised and enlarged edition. 1974;  pp 98-99.
  • Pacific Northwest Solar Radiation Data; UO Sola Monitoring Lab, Frank Vignola, Director; University of Oregon; April 1, 1998.