Fermentation acts as a catalyst for the flavors and colors associated with Darjeeling tea. The tea develops the pungency, strength, and aroma that will be in the final cup.
This takes place on fermentation tables. At Goomtee and Bannockburn, these are portable sheets of steel no more than six feet long, carried like triage gurneys, and stacked on top of one another as needed in front of the rolling machines. Castleton has eight white, polished tables, roughly twenty-five feet long by about six feet wide in a well-lit side of the factory below windows that look out over a steep valley to the east of Kurseong and onto Mount Kanchenjunga. Nearby, Makaibari uses a set of concrete bunks with four tiers in a dim, partitioned corner of the factory. The tea goes on long, metal trays with lips like oversize baking sheets, which are carried by two men. The much larger Tukvar has well over a dozen similar bunk-bed-like tables, sturdy and given numerous whitewashings over the years, that hold the wide metal trays of fermenting tea. Marybong’s setup is altogether different: Four waist-high stainless-steel tables some twenty paces long run across one end of the factory and are cared for by men in blue jumpsuits and baseball caps who, excluding their flip-flops and lack of grease stains, look like mechanics at a chain of oil-lube shops.
While the beds may vary, their purpose remains identical. On them, workers spread the leaves in a thin layer just a few inches deep so they can get plenty of the air required to oxidize. Except during the first flush, when fermentation is short, this step takes a couple of hours. As elsewhere in tea making, the constants are few, and a series of variables change from day to day—temperature, humidity, and leaf quality, as well as the desired strength of the final tea. Gauging exactly how long to ferment falls outside the realm of the intellect or even a reliable calculated equation, residing in instinct, experience, and the nose. As the leaves take on their distinctive coppery-brown color, managers or assistants repeatedly scoop handfuls of the leaves to check their progress by smelling them. The aromas have ripened, become sweeter, and exude hints of dried fruits and nuts: mellower as opposed to sharper; richer. “Smell is what decides fermentation,” said Rohini’s Singh, pressing a handful of fermenting autumn flush to his nose. This is the only way.
The flavor line climbs steeply like a wave, increasing to what Sarki calls “the first nose,” decreases for two or three minutes, then goes up again to the “second nose,” where it peaks before dropping off sharply. The goal is to find that topmost crest, the point when a particular batch of tea is at its best—and then fire the leaves immediately to stop the fermentation before their qualities begin to fade. “If it goes past the second nose, you can’t get back flavor,” Sarki said. “It’s lost.” While the leaves are fermenting, he sniffs them every ten or fifteen minutes, even more frequently toward the end.
Determining that moment is the most critical part of tea making. Every leaf on the bed does not ferment exactly the same, and a majority approach is used when gauging the overall progression of the batch. Underfermented, the finished tea will be brownish and brittle, the liquor less bright, thin, with less body; overfermented, it turns blackish, the tea loses its sheen, turns flat, and Darjeeling’s refined lightness becomes heavier and stewy. At Makaibari, as with withering, Sarki makes the call. He’s slight, with tiny, deep-set eyes, a reluctant smile, and a trademark soft, Nepalese Dhaka topi cloth cap in a woven black, red, and silver pattern. Born on Makaibari—his father was a laborer on the estate—he is the most senior man in the factory. But this isn’t why he is responsible for this key decision. Sarki possesses an extraordinary olfactory gift, a once-in-a-generation talent, according to Rajah Banerjee. “He’s a bloodhound.”
The correct fermentation offers a balance of aroma, brightness, briskness, and strength. Compromises must be gauged and weighed, and a proper equilibrium found among those attributes for the final, desired cup. This depends on each garden and on each tea maker.
“When you are fermenting or oxidizing teas, there are the two aspects of the cup [you are looking for],” Sanjay Sharma explained one second flush morning in the Glenburn factory. Bright, glary light flooded in through the large windows, giving the wooden floor beams, polished from wear, the clean shine on an old dance hall. “Firstly, you’ve got the texture, the mouth feel.” This is the body, the briskness. “And then you’ve got the aroma and flavor.” He held his two index fingers together and moved them up and down in parallel. “It’s a different set of compounds that are working, simultaneously, towards, say, flavor and texture.” He began to move his hands as if juggling billiard balls. “But they don’t always move together, you know?”
Sanjay talks quickly and peppers his sentences with you know, yeah, and okay. These seem less like questions—even rhetorical—than a way of letting the listener catch up.
“You might have a tea that you know has an exceptional nose, a good flavor. But it might be very thin in the cup,” he continued. This is in part because aroma compounds develop earlier in the process. “And then you want that ‘perfect cup.’ You want that flavor and you want that body … it doesn’t always happen, okay. So you have to decide what you want to highlight.” It’s about trade-offs. “The elusive ‘perfect cup,’” he said later, almost wistfully. “It doesn’t exist.”
These natural products are not industrial. Nothing is certain in making them. The materials are continually changing, their reaction never fully predictable. “Making tea,” Sanjay said one autumn evening on the verandah of Glenburn’s old planter’s bungalow, “is like calling your shots on a pool table.”
Once leaves are judged to have reached their fermentation peak, workers quickly tip them into the dryer’s hopper to inactivate the enzymes and microorganisms at work. By removing the moisture with heat, fermentation is stopped, and flavors get sealed in.
The dryers are boxy and oversize rectangular machines six or eight feet tall and twice as long that surely looked futuristic a century—even a half century—ago. A conveyor belt slowly zigzags from top to bottom for twenty to thirty minutes in about 240-degree-Fahrenheit air. Looking through one of the small, smoked-glass windows in the side of the dryer as the tea slides by under a red lightbulb feels more like peering into a darkroom than an oven. The last of the moisture gets wicked away—the final moisture content is only 2 percent—before the tea cascades into a trough at the bottom front of the dryer.
As with any baking, the duration can’t be too long nor the temperature too hot, or the tea gets overly crisp or simply dried out. This gives the liquor an unpleasant baked flavor or even stronger burnt one. While it depends on the flush and the climate and even the elevation of the garden, times are specific. “It is precisely twenty-three minutes,” a factory manager on Makaibari said during the first flush. “Not twenty-two, not twenty-four.” At the end of the second flush, with larger leaves, stronger brews, and more humid conditions (the rains had just begun), the time had been increased to—precisely—twenty-six minutes. At Namring in the Teesta Valley, 2013 first flush teas fired at 230 degrees Fahrenheit for twenty minutes, but as the leaves became coarser and could handle a harder wither and a harder roll, both time and temperature gradually increased. Second flush ones got twenty-three minutes at 250 degrees Fahrenheit, and autumn ones twenty-five minutes at 255.
From the trough, the tea is lifted out using a white-bladed shovel with the type of wide, curved scoop used for clearing snow. A bin of still-warm and slightly brittle leaves exudes lovely, toasty, lightly caramelized aromas and carries a heightened smell of tea in the same way that warm loaves fresh from a baker’s oven carry an intensified scent of bread.