Category Wine Science

Sensing Minerality: an article in Wine Business Monthly

WBM April 2013 Cover

As some of you know, my professional training finds home in the rigors of philosophy. The discipline’s approach takes step number 1 as clarity–asking what exactly are we talking about becomes an integral aspect of any conversation.

Wine Business Monthly hired me to write a freelance article on the rather esoteric subject of minerality. It’s a topic, I believe, that is relevant to considerations of wine but has found issue from being used inconsistently. With that in mind, the article looks at interviews with people knowledgable on the subject, and at current scientific research on it to consider different ways the term minerality is being used, and what we know about the causes of the different qualities behind each of those uses.

If you’re interested in reading more, you can find the article in the current April issue of Wine Business Monthly, available beginning today.

Here’s the direct link to the article (you sign in at no cost):

There’s lots of other interesting stuff in the April issue including examination of how the heck Optical Grape Sorters work (I find this fascinating), and analysis of both the North Coast AVA and the San Joaquin growing region.

If you’d like to see the magazine in an interactive pdf, click here:

In the pdf version the Minerality article appears on page 28.


Copyright 2013 all rights reserved. When sharing or forwarding, please attribute to

One More Consideration of Colli Orientali del Friuli: The Role of Environment, Calcium, and Finally Minerality in Good Tasting, Good Aging Wines of the Appellation; Or, Let’s Make This Title As Long As Possible, Shall We?

In traveling through Friuli-Venezia Giulia, and tasting the wines of Colli Orientali del Friuli, I became fascinated with the fact that the region itself seems to support more natural approaches to vineyard maintenance and wine production. In closing my series on the #cof2012 visit to the appellation I want to indulge my own geeky tendencies and consider the way in which environment, soil, and specifically calcium intersect to encourage the possibility of this more natural approach, as well as the aging potential of the wines. Doing so will lead too to thinking on the controversial, and somewhat esoteric idea of minerality in wine.

Wine Growing Practices in Relation to the Surrounding Environment

Approaching Solder

Friuli-Venezia Giulia celebrates generally cool temperatures and drying bora wind that offer an ideal climate for growing grapes, plus the drying conditions that allow for maintaining healthy fruit. As a result, it is generally easier for wine makers in the region to use more natural practices in the vineyard since there is less need to intervene to avoid fungal or mildew infections on the plant. However, the region offers other natural supports for less interventionist and more chemical free wine production as well.

Many of the smaller wineries also take advantage of their other environmental conditions to develop a more natural wine making practice. As described to us by Ivan Rapuzzi of Ronchi di Cialla, by maintaining vineyards near forests, the pest-predator balance found in the forests is extended to the vineyards as well. That is, many of the pests that strike grape vines, causing detrimental effect for wine makers, can actually also be found among the plants and trees of a forest. The difference in the forest environment is that a balance of pest and predator is more readily maintained so that the overall health of the forest stands even in the face of including some various plant pests. Vineyards, on the other hand, are often designed in such a way that isolate grape vines from other plant life, and as such remove them from the kind of natural balance Rapuzzi describes of the forest. The result is that vines become more vulnerable to pests as they are also in these conditions isolated from the predators that would rid plants of their parasites. By planting grape vines in close proximity to forests the predator population of the forest is available to the neighboring grape vines as well, thus keeping troublesome pests largely at bay. Additionally, proximity to forests helps to keep temperatures well regulated for the steady ripening of fruit.

However, the overall environment found in temperatures, winds, and botanical balance are only a portion of the story for the wines of Colli Orientali del Friuli.

Considering Colli Orientali’s Soils

The View at Le Vigne di Zamo

The ponca of Colli Orientali originates from its years as an Eocenic sea bed. The waters reached almost to the southern rim of the Julian Alps, gathering a rich blend of minerals in their soils, and also a high concentration of organic materials as sediment gathered on the sea floor over time. When the sea retreated, the hills and valleys of the eastern side of Friuli (including both the appellations of Colli Orientali del Friuli and Collio) retained soils valuable for growing low yield grapes with concentrated flavors and rich mineral elements.

The wines of Colli Orientali del Friuli are known for having superb aging ability, with the whites in particular matching the aging ability of those from Champagne and Burgundy. In meeting the Rapuzzi family of Ronchi di Cialla, Ivan discussed with us their own production history testing various techniques and their effects on wine as it ages. What they discovered from the practice was that the less the family intervened in the cellar the more readily the wines lasted well in the bottle over time. Ronchi di Cialla wines are known for doing quite well over extended periods, whether the wine be red, white, or a sweet wine. In their view, this reality confirms that the reason for Colli Orientali’s age-ability originates in the soils themselves, since it is clearly not merely a matter of the strength of individual grape types, for example.

Wine makers throughout Colli Orientali discussed their pride in the value that the soil imparts to their wines. The area consistently produces wine with a distinct mineral zing that shows itself readily in any of the lower intervention wines, and stands up against the more interventionist production techniques of other wine makers as well (that is, as Stuart George would put it, some wines have more make-up).

In considering both the sustainability in the bottle, and the mineral zing of the region’s wines, the wine makers regularly stated that it was the region’s soils that did the work for them, and that, in particular, the high proportion of calcium accomplished these feats.

The Role of Calcium in Root Development

The View from the Top of Ramandolo

Colli Orientali del Friuli celebrates a calcium rich marl, their ponca, which uniquely contributes to the quality of the region’s wines. The presence of calcium in particular stands as important here. Though the calcium rich soils of the eastern side of Friuli-Venezia Giulia are generally understood as too poor for grain or cereal type crops, the soils offer beneficial characteristics for grape vines.

Calcium plays a tricky balance in its benefits for vine growth. On the one hand, calcium rich soil does well at absorbing water during heavy rains (rather than rain simply running off the surface), while then retaining moisture for good periods after, during dry weather. The retention of water in this way allows the security of vine growth over time. However, on the other hand, during longer dry periods the cells of such soils dry up and shrink as the water evaporates, causing cracking and tightening of the ground (though not necessarily in a visible way). While the roots of the vines have been nourished by the water retention of the soil, they now are able to dive deeper through the earth that, due to its cellular shrinking, readily breaks up and makes room for the roots to move through. Thus, the vines receive the nourishment necessary to achieve basic root growth, and then have ease enough to achieve deeper root growth. In pushing into deeper earth, the vines are also forced to struggle in a way that impacts the production of the fruit, concentrating the juices of them and thereby also their flavors.

The benefits of calcium rich soils, however, extend beyond mere questions of moisture.

The Role of Calcium in Vine Development and Fruit Health

Vineyards at Solder

The presence of calcium in soil directly impacts the overall balance of minerals (essential plant nutrients) absorbed and utilized by grape vines, and plants more generally.

Calcium rich earth is generally more porous, or permeable at a small scale in a way that allows greater ‘openness’ (to speak loosely) within the soil structure. These small spaces serve to provide room for root hairs to more readily absorb nutrients directly from the earth itself. The more permeable the soil is in this way the less the plant must compete to take up the minerals needed and already present in the soil. That is, it is not enough for necessary minerals to be present in the soil. The proper conditions that support the plants ability to absorb those minerals must also be present. Soil permeability is one of those conditions.

Calcium also directly impacts the pH level of the soil, keeping the ground from being overly acidic. With more basic (less acidic) soils, vine roots are more able to take up necessary minerals that support the overall plant health and development. In this way, the presence of calcium in the soil allows plants to absorb a healthy balance of calcium, potassium, magnesium, and sodium.

The absorption of these minerals strengthens not only the overall health of the plant, but also the plant’s resistance to external pests. When absorbed by the vine, calcium strengthens the cellular walls of the plant itself, thereby reducing the potential impact of both external pests and enzymes, such as those caused by mildew or fungus. In testing of grapes, calcium actually shows at detectable levels within the fruit skin, and there has the effect of reducing the permeability (and also therefore the susceptibility) of the grape.

Testing has also shown that the absorption of minerals by the vine from the soils directly impacts both the acidity of the grapes, and so then also the pH of the wine itself. In this way, the mineral qualities of the soil do directly impact the sensory qualities of the wine as well–that is, the flavor and structure of the wine. However, the minerals within the soil also impact the degree to which a vineyard manager, and wine maker are able to achieve a less interventionist, and non-petro-chemical approach in making their wine. That is, in the case of calcium rich soils, it is easier for vineyard managers to use less interventionist vineyard maintenance, and to avoid petro-chemical treatments as the balance of the vineyard translates into the pest-resistance of the vines and fruit.

The Question of Minerality in Wine

Vineyards at Betulle

While scientific studies have clearly shown that the minerals within the soil directly impact the pH of the grapes in a manner that persists in the wine produced from that fruit (allowing for variations from production choices, of course), controversy around the question of a wine’s so-called “minerality” remains. What is important to point out here, in the midst of this particular discussion, is that minerality as a descriptor of a wine’s particular qualities is not necessarily a claim of the literal minerals present within that wine. That is, there are at least two different concepts operating here–on the one hand, the role of literal minerals on wine, and, on the other, an idea of a flavoral and textural quality experienced as something like minerals, which we reference as minerality.

Let me give away the beans and cheese of the point I’m going to make, and then make my argument for that point. Here it is, the beans and cheese: My point is that these two things–literal minerals, on the one hand, and minerality in wine, on the other–might have a direct correlation such that literal minerals in the soil are tasted as minerality in the wine, but whether that turns out to be the case, or not, in stating that one tastes minerality, one need not also be claiming that there are literal minerals being tasted. (The question of a possible link is not yet proven and many people because of that argue the correlation is not there–such a claim, however, is sloppy science. Science has not disproven the link.)

Now let’s turn to the clarification of this point.

First, let us consider the role of literal minerals on wine. It is without doubt that differing soil types carry different minerals, which are not only necessary for the growth of any plant, but also that those minerals within the soil directly impact the way in which that plant grows. Further, the mineral presence of the soil, and the soil permeability, not only allow for plant growth but also distinctly impact the quality of the fruit grown by the plant. In the case of wine, the pH levels and chemical balance found within the fruit are a result of the way in which the plant is able (or not) to take up calcium, potassium, magnesium, and sodium from the soil. So, the minerals of the soil simply are relevant to the wine that is produced from vines growing in that soil. Notice, however, that this is not a claim that we literally taste the individual minerals themselves in any direct way. (In fact, the results of most studies would seem to indicate that the levels of any of these four minerals in wine is too low for us to detect as anything like specific flavors.)

Second, let us consider the idea of minerality in wine. We can understand the word minerality, loosely speaking, to reference a sensory experience of something like the flavors and scents of particular minerals themselves, without that experience having to have a direct link to those literal minerals. It is often considered a peculiar description because it seems as though we don’t go around eating, tasting, or smelling the kinds of things wine tasters reference when discussing the notion of minerality. To understand what I mean, we can simply list off different examples of wine terms that are types of apparent minerality: the smell of chalk in champagne; the taste of river stones in a cool vintage Brunello; the scent of petrol in Riesling; the flavor and bouquet of graphite in a rich Bordeaux. In such cases, the term minerality is meant to capture a sensory experience had through the smelling and tasting of a particular wine, a sensory experience where we feel as though we are recognizing something very much like chalk, river stones, petrol, or graphite.

There has been much discussion (much of it argumentative) recently (and indeed for a long time) on the seemingly esoteric notion “minerality.” Many of the arguments depend on a mistake of concept–that is, they assume that the description “minerality” is being stated as a claim of actual mineral levels of the wine itself; and, further, that if there is no such link to actual minerals, then the concept minerality must be faulty. Such a link would depend on testing the wines themselves for those mineral levels. However, continuing to utilize the idea of minerality as a description of a particular wine’s qualities does not genuinely depend upon whether or not there is an actual link between the experience of something like mineral scents and flavors, and there being those actual minerals present in that wine. This is a mistake of assuming that our subjective language of experience can only be supported by systematic scientific legitimization. That is not only false, but also a misunderstanding of (a) the purposes of science, (b) how we experience the world, and (c) how we communicate such experience with each other.

As is no doubt obvious by now, I am fascinated by such questions as, is there a link between minerality in wine and minerals from the soil that wine’s vines were grown in? I honestly want people to continue scientifically studying this. Or, as another question, which I’ve addressed in this post, in what way does calcium impact the growth of vines and the qualities of the wine those vines produce? But, I am equally as fascinated by our own experience of the world, and how we communicate and share with each other such experience.

As an example, scientific studies have pointed out that apples, potatoes, and onions have a chemical make-up that should mean they taste the same. My experience of these three foods, however, is something more like tart and/or sweet for apples, earthy and watery for potatoes, and sweet, sharp, and/or biting for onions (it is apparently the smell of these foods that causes us to distinguish them). In the wines of Colli Orientali del Friuli, however, I taste a minerality I can’t help but love.