That sounds like a curious question at first. Rhythm refers to the placement of sounds through time. But an ordered pattern of blinking lights might also have a rhythm. Sound is not essential to the concept; anything that displays an ordered sequence through time could have a rhythm. So what is the ordered pattern through time that a wine displays? A wine’s features aren’t displayed all at once. As the wine moves across the palate we sense some of its features sequentially. Usually the fruit appears first, flavor and aroma notes emerge and disappear, at some point we begin to sense the acidity, and then the tannins, and as the wine evolves in the mouth these components expand and contract, jostling for our attention, their relative degrees of prominence fluctuating with differing degrees of duration and acceleration.
So I think wines do have rhythm. The question is does that matter. Is their some relation between rhythm and quality? Music of course has rhythm but there isn’t some type of rhythm that is preferred by listeners. What matters is not the type of rhythm but the cohesion of the rhythmic elements and especially of the musicians playing the rhythm. Yet, in any reasonable complex piece of music, the musicians are not playing the same rhythm. Cohesion is not based on sameness but on variations that seem to communicate with each other. (Listen to Ron Carter and Tony Williams on Miles Davis’ Seven Steps to Heaven for an example.)
That gives us a clue about how a wine’s rhythm matters. As the various components of a wine are displayed through time they do not appear in unison but diverge sharply and may appear to be in tension with the acidity straining to be noticed, the tannins relentlessly becoming more prominent, the fruit power trying to hold onto its dominance. Some wines display a great deal of tension; in other wines the struggle for attention is more reserved and full of finesse. But in any case, in a wine of high quality the various elements are constraining each other, working together at key moments to reign each other in, each providing an anchor that the other’s play off of. Even a display of searing acidity or chewy tannins seems to hit the mark. Wine critics used to call this the “knit” of a wine which is helpful but doesn’t describe the dynamic element. In the end, great wines have a sense of effortless resolution. All that tension finally settles on a direction with all the contrasting elements finding a balance point that seems complete. No component failed to deliver, but nothing was left exposed and the dominant elements feel properly limited by contrasting elements. The final movement settled into its pocket.
If I had to choose one property of a wine that is the most reliable indicator of quality it would be this sense of effortless, rhythmic resolution. There is no single word to describe it. “Elegance” or “gracefulness” is appropriate for some wines but there are some wild and wooly beasts—a great Amarone for instance–that nevertheless achieve this resolution.