Gulp: Adventures on the Alimentary Canal

Next is a “triangle test”: three olive-oil samples, two of them identical. Our task is to identify the odd one out. We are given paper cups of water for rinsing and, for spitting, large red plastic cups of the kind that litter the lawns and porches of frat houses on weekend mornings. The red here today perhaps serving as a warning: Do not drink! Langstaff sits at the front of the room, reading a newspaper.

It’s not going well here in the B.R. Cohn Winery seat. All three oils taste the same to me: a hint of freshly mown grass, with a peppery finish. I do not detect apple, avocado, melon, pawpaw, old fruit bowl, almond, green tomato, artichoke, cinnamon, cat urine, hemp, Parmesan cheese, fetid milk, Band-Aid, crushed ants, or any other olive-oil flavor, good or bad, that might set one of these oils apart. With time running out, I don’t bother spitting. I’m sipping oil like it’s tea. Langstaff glances at me over her glasses. I wipe my lips and chin with my palm, and a shiny smear comes away.

Our final challenge is a ranking test: five olive oils of differing degrees of bitterness. This proves a challenge for me, as I would not have described any of them as bitter. All around me, people make sounds like ill-mannered soup-eaters, aerating the oils to free the aromatic gases. I’m doing a mnyeh-mnyeh-mnyeh Bugs Bunny thing with my tongue, but it’s not helping. Well before the test period ends, I stop. I do something I’ve never done in my entire overachieving life. I give up and guess. I do this partly at the behest of my stomach, which is struggling to cope with the unusual delivery of a sizable amount of straight olive oil.

After everyone else leaves, Langstaff shares some of the group’s answers (with names removed). Those who performed well on the oil rankings—incredibly, several got it close to exact—also noted that aroma number 7, on the first test, was not just olive oil, but rancid olive oil. Four out of twenty people, all olive professionals, nailed that detail. (The oil smelled fine to me. I was right there with the numb-nose who wrote, on his answer form, “Oh, for a piece of good bread!”) Here’s what I find interesting. The people who work with olives and olive oil, most of whom performed supernaturally well on the ranking and triangle tests, were occasionally stumped by some of the most common and, to me, obvious aromas. A woman who, in the initial sniff test, realized that the olive oil was “rancid, fusty” failed to recognize almond extract. She wrote, “Cranberry, fruity, sweet, aloe juice.” She described diacetyl, the smell of artificial (movie popcorn) butter, as “licorice, candy, bubble gum.” Those aren’t important flavors in the day-to-day of the olive world, so there’s no reason for her to know them. This supports what Langstaff said earlier. As with any language, proficiency builds with exposure and practice. (Though not quickly; the average training period for a sensory panelist is sixty hours.) In my case, it won’t be happening any time soon. An e-mail from Langstaff arrives around nine that night. “Hi Mary. Hope you enjoyed the tryouts. Unfortunately you did not make the cut.”

SENSORY ANALYSIS IS not limited to the epicurean industries of Napa Valley. For any food or drink manufactured on a reasonably large scale, there are trained panelists and sensory descriptors. Poking around in the sensory-science journals, I have seen flavor lexicons for mutton, strawberry yogurt, chicken nuggets, ripening anchovies, almonds, beef, chocolate ice cream, pond-raised catfish, aged Cheddar cheese, rice, apples, rye bread, and “warmed-over flavor.”

The work entails more than just troubleshooting. Sensory analysts and panels help with product development. They keep the flavors of established products on track when a formula is altered—say, to lower the fat or salt content. They work with the market research staff. When focus groups of consumers prefer one version of, say, a ranch dressing over another (or over a competitor’s dressing), sensory evaluators may be brought in to figure out the salient attributes of the more popular item. The food scientists can then work backward from those attributes to tweak the formula.

Why use humans rather than lab equipment? Because the latter would yield dozens of chemical differences* between a pair of products. Without a human evaluator, it’s impossible to assign sensory meaning to them. Which of those dozens of differences in chemical makeup translates to a perceptible flavor shift, and which is below the threshold for human detection? Which ones, in short, make the difference in the consumer’s mouth and mind? “And you can’t ask the consumer,” says Langstaff. “You ask the consumer, ‘Why does it taste better?’ They say, ‘Because I like it better.’” The consumer’s flavor lexicon is tiny: yum and yuck.

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