Supermarket Whole Bean Coffee

Overview: We secretly replaced our tasters' favorite gourmet coffee with supermarket beans. Could they tell the difference? Our taste tests yielded surprising results.

When Starbucks started offering its whole beans at the grocery store, we took notice. Amid the instant-coffee "crystals" and the tin cans of preground coffee sat several shelves' worth of whole-bean coffee brands. Some hailed from other coffeehouses, vying (like Starbucks) for a piece of the lucrative coffee-aisle action; others were straight-ahead supermarket brands, priced per pound at less than what you might normally pay for a single iced-venti-no-foam-latte.

To find out how they competed, we bought eight whole-bean coffees at the supermarket, choosing the "house blend," or whatever medium roast was widely available. Test kitchen staffers first tried the coffees brewed regular strength. The differences were striking. Some coffees were strong and smoky, others tasted light and "chocolaty," still others boasted hints of caramel or molasses. For a few of the brands, the tasting sheets overflowed with invective decrying bitter, rancid, or harsh qualities.

We then devised one more test--a tasting of coffee with milk. An informal poll revealed that more than two-thirds of the Cook's staff add milk to their coffee, and it seemed only fair to try the brands that way, too. So we brewed up eight more pots, added 3/4 cup warmed whole milk to each, and summoned 25 soon-to-be-jittery tasters into the test kitchen for another tour.

Sure enough, preferences changed. This time, the plain-coffee champs ended up in the lower ranks--bland and insipid, according to tasters. In contrast, three fairly assertive coffees landed at or near the top. The bitter, burnt notes that had menaced tasters in the first round were suddenly "robust" and "complex" when tempered by the milk. Simply watered down? Not quite. Additional research revealed that the proteins in milk (and cream) bind some of the bitter-tasting phenolic compounds, reducing the bitterness and intensity of the coffee flavor.

Dark Matter

So far we had based our analysis on subjective descriptions. But there was a better way. In general, the longer a coffee bean roasts, the darker and more strongly flavored it becomes. Although it's possible to make a rough comparison of roast darkness by eyeballing alone, experts use an instrument called an Agtron to measure exactly how much light the beans reflect. The higher the Agtron reading (that is, the more light the beans reflect), the lighter the roast: An Agtron reading of 85 would indicate an ultra-light, almost tealike coffee; the darkest French roast out there would be closer to 15.

To find out how roast darkness lined up with taster preference, we sent the samples to a lab that specializes in coffee analysis. The Agtron readings differed markedly. From this data, we learned that roast darkness correlated with our tasting-room experience: Two lighter roasts triumphed in the plain tasting yet proved too mild in the milk round. By contrast, the three darkest roasts were the milk-round champs. Still troubling was how to explain the three brands that stubbornly refused to play by the light-roast/dark-roast rules.

Grounds for Dismissal

Luckily, some of the best discoveries happen by accident. The lab we hired to measure roast darkness had included several other tests including an odd-sounding measurement involving the number of “quakers”. Turns out, a quaker is coffee-industry jargon for an underdeveloped coffee bean that fails to get sorted out before the roasting stage. Less dense than a regular, mature bean, quakers can wreak havoc on the coffee's flavor profile, imparting a spoiled taste to the brew. So desirable is quaker-free coffee that beans are graded based on quaker count, and buyers are willing to pay a premium for beans that come up clean in spot tests.

The lab had found quaker counts in our coffees ranging from 0 to 9--based on a 100-gram sample (just over a cup). Do those numbers really matter to the casual coffee drinker? In a word, yes. We dumped several bags of coffee onto the countertop and sorted out the quakers, then brewed a fresh pot of coffee made entirely from quakers. The smell was putrid enough, but the first taste dispelled any suspicions that quaker count was merely some academic exercise. Suffice it to say a quaker is indeed something best avoided.

Beyond roast darkness and quaker count, the experts also acknowledged that the brands in our lineup draw from raw (or "green") beans of varying quality. But spending a mint on prime beans doesn't guarantee a tasty brew, in fact dark roasting obscures many of the nuances.

So where did we come out? Turns out it is possible to get good whole-bean coffee at the supermarket, but you may have to spend premium prices.