The Ultimate Question of Terroir ~  The Most Significant Vineyard Study

Correlating Soil Nutrients to Flavors

We all know quite well that a wild blueberry picked in the woods of Maine, or a tomato grown in a backyard with nurtured soils, or that ripe plum plucked from your tree in wild soils tastes nothing like the fruit and vegetables we now buy in our super markets.  The gene-splicing in these frankenfoods are a serious problem, but the major issue is that they are grown on shockingly mineral-depleted soils.  That fact and that alone is why there are no flavors present in these frankenfoods. 

Flavors derive from minerals.  It is a simple fact and nature's way.  Health derives from minerals.  All major experts on this subject agree that most of the diseases in this country, like diabetes which is now at epidemic proportions, and obesity (a mineral-starved condition) find their root cause in the mineral depleted soils that dominate our corporate farmlands.

And so it is with wine.  Almost all of the wine made in this country derives flavor stucture from oak barrels or chips and winemaking manipulation.  But with the newly evolving interest in "terroir" and the concept that the best wine is the "signature of the soil," what is actually known about soils and minerals and the relationhip to flavor in wine?  The answer: not much.

These questions which have much to do with this overarching concept of terroir and a "sense of place" were in part the questions that prompted the most significant long-term research efforts ever undertaken regarding the impact of soil types, nutrients, and properties in regards to wine quality and flavor perceptions.  This research found its ideal location -- Carmody McKnight Vineyards.  The understanding of this critical soil-terroir-wine quality relationship has long been pursued, especially in Europe.  In fact, for centuries; but because of newly developing technologies, this was now the time and Carmody McKnight was now the place.

The Most Important Vineyard Research Ever Undertaken

All of the major soil constituents (such as limestone, calcium montmorillonite, volcanic intrusion, etc.) known to profoundly support superior wine quality exist in the vineyards of Carmody McKnight and probably nowhere else.  This unique combination of soils coupled with ideal microclimates make the vineyard a one-of-a-kind laboratory on a course to vastly affect quality winemaking as we know it -- around the world.  For the first time the quality perception of wine - which has always been illusive and subject to varying personal interpretations was to be scientifically investgated with a constancy of parameters and vineyard and winemking controls that heretofore were not available.

This seminal study which correlates soil nutrients to flavors would not only confirm but analyze the process of minerals to taste perception -- the ultimate challenge of terroir. The Project Title: Assessing the Relationship of Wine Quality to Soil Type: A joint project between Cal Poly Earth and Soil Sciences & Food Chemistry, Food Science, Nutrition, & Statistical Departments, John Deere Global Ag. Services, State of California, Earth Information Technologies Inc., Motorola, and Carmody McKnight.

Carmody McKnight managed the varietal selections and winemaking processes.  The project is directed by Thomas J. Rice, Ph.D., C.P.S.S., Professor of Earth & Soil Sciences, California Polytechnic State University (Cal Poly), Earth and Soil Sciences Department; Joseph Montecalvo, Ph.D., Professor of Food Chemistry, Food Science and Nutrition Department Cal Poly, and the Department of Statistical Research, Cal Poly.  

The studies are a joint effort between the State of California, the above departments of Cal Poly, John Deere Global Ag. Services (with Mark Stelford, Ph.D.), Earth Information Technologies Inc. (EarthIT; Dan Rooney, EarthIT President) and Motorola, providing atmospheric and soil monitoring stations.

Professor Thomas J. Rice prepared the following project synopsis -- project title: "Assessing Wine Quality Relationships to Soil Types"

1.  Produce detailed soil map for Blocks 3-4-5 of Carmody McKnight vineyards.  (Use existing EarthIT information from June 2003 to revise previous soils maps conducted by the Cal Poly and the USDA).

2. Obtain soil physical and geochemical properties (to four feet) for the major soils in these blocks.  Describe each soil according to USDA standards, sample each morphologic soil horizon, and obtain geochemical data for all morphologic soil horizons.

3. Based on the soils maps and soils data, partition zones within the wine grape varieties  (Cabernet Franc-Bl. 3,  Merlot-Bl. 4, Cabernet Sauvignon-Bl. 5).  A wine grape plot sampling will be designed to sample grapes from the same variety on significantly different soils, all other factors being equal.

4.  Assess the wine grape quality parameters (inorganic and organic components).

5.  Statistically compare the "inorganic" wine grape parameters with the inorganic soil geochemical properties.  Statistically compare the "organic" wine grape parameters among the different soil types.  Dr. Montecalvo will conduct the wine property analyses to begin to determine the differences between the wines harvested on varying soil types, all other factors being equal (grape variety, climate, vineyard management, etc.).  A sampling regime will be conducted to capture changes/differences in the chemistry/flavor profiles.  The group will measure the most important "grape must" and "wine" organic and inorganic properties in order to distinguish differences among similar genetic wine grape varieties grown on differing soil types.

The result: Terroir has become a science!