Truffles are harvested in winter as that is when they mature.
Traditional truffle hunters have been female pigs, attracted by the aroma that resembles pigs’ sexual hormones. Yet despite their indisputable prowess in tracking down truffles, sows also have a fondness for the valuable fungus. ‘I have heard stories of pigs taking off their owner’s fingers in the wrestle for a truffle,’ cautions Terry, who has opted instead to train a young dog for the job.
‘Dogs have a 21-day imprint period,’ Terry explains, ‘after which they’ll remember something for life.’ So every day for twenty-one days while training his springer spaniel, Hoover, Terry played increasingly complicated retrieval games. Using a film canister of cotton wool drizzled with truffle oil (‘Canitruf’ – a French product designed specifically for training dogs to find truffles) as bait, Terry would initially reward the dog to fetch and return the canister. The game graduated to the dog having to find canisters buried around the roots of trees where truffles were likely to be found. The process is not without fault, however, and dogs have ‘about an hour’s’ concentration span, according to Terry, before they need a rest.
Mechanised detection systems have also proved successful in testing, with a pre-programmed automated ‘nose’ sniffing out truffle spore. The electronic nose was developed by Terry and Professor Bryn Hibbert of the chemosensory department at the University of New South Wales, but until Terry’s plantations are large enough and commercially viable enough to complete the half-million-dollar machine, dogs are still the best means of truffle detection.
A machine can get close to the truffle, but can’t pinpoint it exactly, which is why the last word remains with the human nose. ‘It’s a cold, wet occupation,’ says Terry, who demonstrates the final stage: when the dog has sniffed out a potential truffle, Terry gets down on his knees and sniffs around the area. Truffle hunting is best at about 10 or 11 a.m. as a truffle’s aroma needs the gentle heat of the day to sufficiently intensify for detection. A ripe truffle will emit such a strong scent it is distinguishable from just above the ground to the human nose. Gently prising the earth, care must be taken not to damage the truffle as it’s being unearthed.
It’s obvious that a truffle spore has inoculated the area around the roots of a tree by the presence of what’s known as a brulé. Like the culinary version, brulé in this sense means ‘burnt’, and refers to the parched appearance of the circular area of soil around the base of the tree. The brulé generally expands to occupy the diameter of the tree’s branch span, killing grass and any other plants living on it.
It is the brulé that has been a time-honoured indicator of the presence of a truffle fungi working beneath the ground, but the brulé simply means that the fungus is there and that it’s active. It does not guarantee the presence of truffles beneath the soil’s surface.