Rooibos Tea Gets Its Own Sensory Wheel, Just Like Wine And Coffee
Little rooibos, the humble red tea buttressing the "decaf" side of the after-dinner menu, must be growing up: First, featured in a Starbucks latte. Now, important enough to need its own gourmet lexicon.
This smoky, sweet tea has been working its way into specialty beverages and personal care products on the basis of both flavor and health claims — it's high in antioxidants and naturally caffeine-free. In the U.S., organic rooibos imports are booming with a seven-fold increase in the last decade.
That's according to the South African Department of Agriculture, Forestry and Fisheries, which has a central stake in the rooibos trade. The country is home to all 450 or so commercial rooibos growers in the world, owing to the peculiarities of climate and soil in the region (rooibos likes it a bit on the harsh side, apparently).
Keen to keep a leash on the quality standards of what gets to be called "rooibos," the South African government has commissioned a group of scientists and professional tasters to paint a sensory portrait of the plant's characteristic flavor.
But defining a flavor like rooibos is not as easy as it sounds.
"It's not rose; it's not geranium," said Nina Muller of Stellenbosch University in South Africa, who conducted the rooibos sensory analysis. "There's an herbal floral note which is particular to rooibos." She organized a panel of experienced tasters to swirl, sniff and sip their way through dozens of batches of rooibos tea over the course of several months.
Comparing to a "control" flavor—a blend of several medium-grade rooibos batches—the tasting panel came up with words to describe the tastes and aromas they encountered in 69 different samples. This lexicon of rooibos sensuality was then discussed, pared, and rechecked for consistency. Now the researchers have come out with the first version of a sensory wheel, published in the journal Food Research International.
So what's a tea drinker to look for in a good cup of rooibos? Primarily "honey," "woody," "spicy," and "caramel." Tasting "hay," "seaweed," or "mustiness" is not so good—or at least, from the industry perspective, should be avoided. South Africa's Rooibos, Ltd, the primary distributor of rooibos in the world, is already incorporating the rooibos sensory wheel into its quality control processes, according to Colette Cronje, their quality control manager.
The researchers hope that at the end of their three-year sensory and molecular analysis, they will not only be able to describe the perfect cup of rooibos, they'll be able to tell you where it comes from and how it was processed. Rooibos goes through several processing steps, including a kind of composting fermentation process that turns it from its raw green color to the familiar fiery red and orange. Then it is dried for a certain length of time on "rooibos courts" in the sun before being sorted and packaged.
All of these geographic and agricultural nuances may leave their marks on the tea's flavor and aromas, but before now, there was no standard flavor to use as a ruler.
Tea from one valley in particular is thought among growers to be a strong source of the coveted caramel flavor in some rooibos teas. "We think at this moment that the caramel note is maybe terroir, that you get in wine," said Muller, "but we're not sure yet."
Sensory wheels have come into use for specialty food industries since the creation of the famous wine aroma wheel in the early 80s. "They're a great marketing tool," says Ann Noble, creator of the wine wheel, "they help turn wine or olive oils into a commodity to be valued, and explain why some are more expensive than others."
With its sensory lexicon firming up, the South African government would be delighted to see rooibos go the way of wine or olive oil: so look for a tasting party coming soon to a Whole Foods near you.
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