I'm not talking about the bubbles swarming into foam on top of that IPA in front of you, but something entirely different. It's the bubble inside which every one of us lives, traveling through the world looking out at our own personal version of reality as we drift through it. The Hindus came to this conclusion millennia ago, and in many ways their metaphor is increasingly verified by science. Nothing about our perception is objective. To understand, we must abandon the comforting notion that our senses provide accurate and truthful representations of the world around us.
But beyond the most basic terms, it all breaks down. Each of us has dramatically different sensitivities to every taste and aroma, and may assign wildly differing levels of pleasure or distaste to the sensations. A beer that seems harmonious, pleasant and balanced to one person might taste harsh and unpalatable to another. Our whole life's tasting experiences persist strongly in our memory, modulating every taste and sip. Culturally, biographically and genetically, each of us is absolutely unique. We all inhabit utterly different worlds when it comes to our senses.
How's Your Taster?
Let's start with the simplest place we can—the intensity of various tastes on the tongue. There are just a few of them: sweet, sour, salty, bitter, umami and a handful of less important ones. Over millions of years of evolution, our sense of taste has been shaped by what's good or bad for us in the natural environment and passed on through countless generations. One might think that if we're going to find any common ground, it should be here, right?
Well, yes and no. It's clear that much of our cellular and perceptual machinery is similarly structured from person to person, encoded by inherited genes. There are shared experiences—just look at the harmonious way cuisines develop and the tremendous attachment people have to them. On the surface, we seem to be pretty similar, but when you start digging, the differences between us can seem vast.
We are all differently sensitive to tastes on the tongue, and are particular divergent when it comes to bitterness. That dark and brooding sensation is different from other tastes, as it is meant as a warning against ingesting potentially toxic materials (think strychnine, cyanide, alkaloids). Bitterness is an acquired taste because we are genetically programmed to be suspicious of it.
About 25 percent of people—somewhat skewed to the female side—are exquisitely sensitive to bitterness. It's one characteristic of a group labeled as "supertasters," and as you can imagine, this sensitivity plays a huge role in our preferences at the table. At the other end of the scale are a group labeled "non-tasters," who are much less sensitive to everything, especially bitterness. The rest of us fall into the middle half, but that doesn't mean we're all the same. Our sensitivities—or lack of them—strongly drive our preferences in food and drink.
The wine world has spent years browbeating people into believing there was something wrong with them if they didn't just love big, inky, tannic wines. As a result, supertasters often had to conceal their preference for sweeter, less tannic wines. After some soul-searching, there is some interest in accommodating those more sensitive tasters. Some wine clubs are even having people fill out questionnaires to help identify their "vinotype." Perhaps we may get to a point when we can talk about "zythotypes" with beer drinkers.
We have the same sensitivity differences with aromas. Perhaps ten percent of the population is blind to common beer off-flavors like diacetyl or DMS. Others may be highly sensitive. I'm sensitive to musty/earthy aromas; others I know are super sensitive to metallic, diacetyl and other aromas. Training lowers these thresholds, increasing sensitivity. Taste panel QC programs train and calibrate their tasters; strong or weak responses to specific stimuli are accounted for in the panelists' scoring. Beer competition judges get a sense of their own sensitivities and blindnesses. If your response generally differs from your tablemates time after time, then you learn to take that into account in the way you judge.
There are also enormous cultural differences as well. Our perceptual world is shaped by the continued accumulation of our experiences of tastes, textures, aromas and everything else, making us walking libraries of those past sensations. These are not passive memories, but active mediators shaping our experiences in ways we are just beginning to understand. As with language, our sensory experiences transform our brain, affecting perception. The differences from culture to culture can be pretty dramatic.
What's more, your adult self is very different from the juvenile you—you can probably remember fights over broccoli or Brussels sprouts as a child, their mild bitterness amplified through the lens of an immature perceptual system. Children are known to be several times more sensitive to bitterness than adults. As we advance in age, our chemical senses further diminish. Older people might add two or three times the amount of salt to a bowl of tomato soup as middle-aged ones.
Our bodies and brains change throughout the daily cycle, and our palates are most attuned in the morning, which is why brewery taste panels are usually conducted then. What about your mood? Are you hungry? Thirsty? Those change your perceptual bubble as well.
Not surprisingly, your experience level also changes the way you perceive things. I've observed that newer enthusiasts tend to focus on a few key factors—hoppiness or roastiness for example—and then tend to seek out more of that particular factor. Perhaps this explains some of the scores on the popular beer rating sites that tend to reward intensity.
With experience tasters expand their vocabulary and interests. With more experience they learn to evaluate the style-appropriateness of a given beer. Highly experienced tasters can do two very different things simultaneously: deconstruct the beer into its component tastes, aromas and even ingredients, and develop an opinion about the beer as an integrated whole. You generally don't see such people chasing crazy bitterness. In my experience, a lot of great brewers relish nothing more exotic than a well-brewed pilsner or pale ale.
Other kinds of information can profoundly change the way we experience foods and drinks. Simply reading the word "salt," for example, causes activity in the brain where the salty sensation is actually processed. I don't know if it's been done, but if you presented beer enthusiasts with two identical pale ales, one labeled as 30 IBU and the other 60 IBU, I would bet actual money that a significant majority of tasters would find the 60-labeled beer to taste more bitter. We all like to think that we're above such manipulation, but it's been shown time and time again that we are not.
It has been proven that presenting information about the price or expert's scoring of a wine will change the reported quality/preference by tasters. I expect that other similar factors such as brand prestige and rarity are equally persuasive. By selectively focusing on some of this kind of information, we further modify our perceptual bubbles.
Then there's the power of peer groups. As social creatures, we have a desire to adapt ourselves to the group, and our chemical senses are only too happy to play along. A few words on the label, some comments on RateBeer or a persuasive tablemate, and we will often find the suggested flavor, whether it's there or not. This is the reason beer judging is usually done in silence until scoring is finished, with discussion afterwards.
If you're feeling much less sure about yourself after reading all of this, good. Awareness of our own tasting abilities and preferences as well as sensitivity to the needs of those around us is a sign of a mature and capable taster. So, hop back into your bubble, shut the door, fire up the thrusters and enjoy the ride, hopefully with a slightly different view.