Taming of the shroom: Swetha Sivakumar writes on truffles

Humans have, for the most part, been pretty successful at taming and domesticating plants, and moulding them to our will. But some continue to defy our efforts.

Saffron is one such species (more on that in the next column); truffles are another.

What fascinates me about truffles isn’t their flavour. It’s the story of why they are so elusive, and, as a result, so expensive.

For one thing, they simply do not fit into today’s world of mechanised farming. One cannot “plant” truffles or “harvest” them. One must start by planting a tree whose roots they might like; one must then inoculate those roots with a specific fungal strain, hoping that the tree and the strain will get along — although they most likely will not.
The “farmer” must then wait at least five, if not 10, years, before beginning to search their orchard, with a specially trained animal, for truffles that may or may not have grown underground.
Why can’t any of this be made simpler? Well, like all fungi, truffles cannot perform photosynthesis. Most mushrooms get around this by simply breaking down organic material such as compost — or, in my case, food forgotten at the back of the fridge. (The spores are everywhere around us, which is how they manage to turn up, seemingly out of nowhere.)
Truffles operate differently. They survive by forming symbiotic relationships with trees. They receive sugars from the tree and, in return, use their filaments to gather, from far and wide, nutrients that the tree needs but cannot reach. Given the right conditions, they can thus co-exist in harmony for several years.
Fast-forward several years, then, and the fungi are now mating underground (I have to add here that how they reproduce is still a mystery to science, so I cannot tell you what goes on). With a successful mating, a small knob appears, carrying spores. This immature shroom lies dormant, waiting for the right temperature and moisture conditions to trigger the growth of its spore-filled fruiting body.
The right conditions take time, but finally the fruiting is done. Now, how is this hidden fungus to disperse its spores?
Unlike plants, which invest energy in producing flowers and fruit to attract pollinators and seed-dispersers, the truffle is still underground, so it needn’t bother. What it does focus on is aroma.
A ripe truffle doesn’t look like anything much; the white Alba resembles a potato and the black Perigord looks like a pebble. But each one can release over 200 volatile organic compounds, including alcohols. People describe the flavours of a ripe truffle as heady, earthy, musky. What they’re really describing are the aromas.
This is why the easiest way to find one is with a trained sniffer. The scent typically attracts mammals such as pigs, deer, mice, boar, foxes and bears, which eat the fungi and disperse the spores in their faeces.
Pigs were often used as foragers, because of their fondness for truffles. Now, dogs are replacing them because they can be trained to leave the ripe ones alone once they find them (something the pigs apparently could not be trained to do!).
There is a peak aroma stage at which truffles must be harvested. Jump the gun and one may as well throw the valuable bulb away. An unripe truffle has almost no flavour, and will not ripen once out of the ground.
Even with a ripe, whole truffle safely harvested, though, the drama isn’t done. Once again, they defy all modern standards of food distribution, because there is no way to preserve them. Canning and dehydrating destroy their flavour; freezing compromises both texture and flavour.
Once they are out of the ground, meanwhile, it is a race against the clock. They must be consumed within 10 days. Even within this window, they lose a bit of moisture and valuable weight with each day. And so they are flown around the world in a frenzy, to restaurants that then shave them delicately at the table — because that’s the surest way to benefit from the exorbitant aromatics.
How exorbitant? Truffles sell for €2,000 ( ₹1.8 lakh) to €6,000 ( ₹5.6 lakh) per kg for the white and up to €1,500 ( ₹1.4 lakh) per kg for the black Perigord.
Prices can be expected to rise, as climate change adds to the challenges. France, for instance, produced about 1,588 tonnes of the black Perigord annually in the 19th century. It now yields only 10 to 50 tonnes of these a year, as rising temperatures have hampered truffle formation.
Amid steady demand for the flavour and the tag, chemists have isolated one of the key compounds, and this is why there really is something of a truffle flavour in the more expensive truffle oils and gourmet flavoured snacks. But this is one compound of about 200, so it isn’t anything like the full experience.
Isn’t it incredible that something so gnarled, bumpy and covered in mud should retain such a hold over us, and so refuse to be tamed?
If you’d like more drama from this world, turn to The Truffle Underground: A Tale of Mystery, Mayhem, and Manipulation in the Shadowy Market of the World’s Most Expensive Fungus. The marvellous book by investigative reporter Ryan Jacobs dives into a web of dog poisonings, murders, fraud and other truffle-mafia-don doings.
You won’t ever look at these shrooms the same way again.
(To reach Swetha Sivakumar with questions or feedback, email [email protected])