We perceive five basic tastes: sweet, sour, salty, bitter and savoury. We start out with up to 10,000 taste-buds, clustered on the tongue, the inside of the cheeks, the roof of the mouth and in the throat. Each taste-bud contains specialised receptor cells that send signals to the brain.
By contrast, we can detect thousands of distinct scents, perceiving them through a complex process, which makes it easy to disrupt. How it worked was a mystery until the early 1990’s, when Dr. Richard Axel and Dr. Linda Buck, unraveled the network that governs our sense of smell. It starts with the family of 350 odor receptors clustered at the top of the nasal cavity. There are thousands of specific aromas, and only a single molecule is needed to light up one or more receptors.
Smell sensitivity varies widely from individual to individual thanks to quirks of physiology. Some people are “smell blind” to certain chemicals, such as TCA, or cork taint, for example. We now know that the ability to smell fades much more than the ability to taste. Taste is our most stable sense. There’s some evidence the number of taste-buds declines with age, but people may not notice this because they’re scattered throughout your mouth. If you add in the physical sensations of texture, you can still discern much from a mouthful of wine.
The taste we start losing first is our sense of bitterness. It declines in a measurable way over a lifetime for men, while for women it starts at menopause. Other studies have indicated that perception of salty tastes decreases more than sour and sweet ones. Wine professionals may compensate for a lessened ability to nose out nuances by relying on their experienced palates and detailed taste memories. California-based Dan Berger, 73, who’s been writing about wine for almost 40 years and organizes and judges wine competitions, believes his palate memory is “better than it has ever been” because the vast number of wines he’s tasted from around the world “conjure up sense memories I never had when I was younger.” This is one way that age can be a positive factor in how our brains read smell and taste signals.
Scores of older winemakers, importers, brokers and sommeliers are still using their noses and taste buds to make critical decisions on wines—a fact that should give ageing wine lovers reason to continue to have confidence in their own wine opinions.