For various reasons when people taste wine, we often try to share our perceptions. We describe what we taste and smell through description.
We use language to communicate. The way we do this is by using descriptors, i.e. words that communicate sensorial information, the physical qualities, visual qualities, aromatic qualities and flavor qualities of the wine.
We do this in a way that can be vague or specific but generally that is shaded between positive and negative, as we usually convey both our own experience and preferences simultaneously.
We do this by use of adjectives and by analogy. An analogy is a comparison between things that are not the same, but that share a similarity. I.e. this wine tastes like blackberry, this wine tastes like cat pee, etc.
It is generally accepted and understood that when we communicate that we taste cat pee, or blackberry, or horse sweat in wine, that we are using these descriptors as descriptors by analogy only. Not because there is actual cat pee in the wine.
Similarly most people understand that when we describe mineral characteristics, i.e. the flavor or aroma of rocks or soil, that we really do not taste actual rocks and soil. Rather we are using these descriptors by analogy to express the resemblance between two things that are unlike, wine and rock, in order to communicate a similarity from a sensory perception perspective of a wine’s attributes.
In addition we can use these descriptors to communicate perceptions other than flavor and aroma in wine. For many the description of minerality is a tactile sensation rather than a flavor, i.e. the physical/mechanical impression of wine as a textural impression in the mouth. For this aspect or perception of minerality in particular, flavor scientists believe it is created by the interaction of acid and tannin on the mucosal tissue of the mouth as well as by alcohol and other compounds such as dissolved carbon dioxide.
For clarity of understanding, flavor and tactile perception are two different things. An example is bitterness and astringency. Bitterness is a flavor, whereas astringency is a tactile sensation. Yet both perceptions are related because they generally derive from phenolics compounds in wine and both are perceived synergistically with acidity. Winemakers understand that the perception of tannin that contributes a specific level of bitterness and astringency in a particular wine increases as acidity increases. (Which is why fruit ripeness, tannins and acidity are very important at harvest.)
ROCKS IN WINE? There is a very long and historic tradition that claims that the perception of mineral flavors in wines rather than analogous and similar by way of resemblance, are actually the real flavor of rocks and soil, particularly from hallowed sites with centuries old marketing traditions. These beliefs predate basic understanding of plant biology and microbiology.
Plants do not uptake rocks and soil, no more than they uptake cat pee or black berry flavors. Plants uptake ions, which are used in plant metabolism. This uptake occurs through plant membranes and is mediated by embedded proteins whose expression is controlled by genes that are more or less concentration independent. They regulate nutrient uptake, not uptake of soil, rocks or cat pee.
I have explained this to numerous wine writers whose first response is to object because of the centuries old tradition of terroir being the flavor of minerality from these hallowed sites. Basic plant biology is juxtaposed with historical beliefs, especially those related to marketing mythologies. These beliefs were not based on reality but rather on the exigency of selling wine and creating regional brands over centuries.
These beliefs die hard and slowly. Please, just try to remember that you are not drinking cat pee and rocks. But rather a complex beverage with many flavors and aromas made from fruit that was converted into wine by yeast, bacteria, human intervention and time.
Describe away, but keep it real by understanding that descriptors are used to explain and describe similarities between things that are really not the same.