It's going to be a great winter for truffles. Cold nights and good rainfall have ensured the sought-after subterranean fungi are swelling to a healthy size and developing their essential aromas and flavours, according to truffle experts across Victoria.

What started as a boutique endeavour 20 years ago is now a $70 million national industry with around 300 farmers producing 20,000 kilograms of truffles on orchards from Margaret River to south of Hobart.

When the first Australian truffles arrived in Melbourne from Tasmania in the early 2000s, Matt Wilkinson was junior sous chef at Vue de Monde – back when the acclaimed restaurant was still at its original terrace site in Carlton.

"There was this huge fuss being made over these brown, dry, knobbly things the colour and shape of dry horse manure, all carefully wrapped in tissue paper in a shoebox," says Wilkinson, now executive chef at Montalto Dining in Red Hill South on the Mornington Peninsula.

"The quality and availability has become a lot better since those days. Ordering Australian truffles was once a ludicrous act of conspicuous consumption."

Wilkinson says the value of the luxe tubers has also improved. "Truffles used to be more than $3000 a kilogram, but that was 20 years ago. Today they cost about the same or less."

Wilkinson buys his truffles from Jenny McAuley at Red Hill Truffles, five minutes drive from Montalto.

When McAuley planted her first oak and hazelnut trees in 2005 their roots were inoculated with truffle spores. Over the next 12 months, the truffle fungus, a white web-like mesh called tuber melanosporum, started spreading underground. Five years later, the fungus fruited, producing golf ball-sized black truffles.

McCauley sold her first truffle to Montalto in 2010. Last year, the grower harvested 80 kilograms of the black diamonds with the help of her truffle-sniffing dog Thomas.

"Every season from late May, I hope for cold weather," says McCauley. "Truffles need the soil temperature to be cold in order to ripen.

"This means drops in temperature in May and early June are very good. That's when aroma develops in truffles and becomes strong, which is when we harvest them."

McCauley will sell a good portion of her truffles to other local restaurants such as Tedesca, Max's and 10 Minutes by Tractor. The rest will be sold through farm gate sales and regular truffle hunts for $2.50 per gram over the winter truffle season.

Meanwhile, high-end food purveyor Simon Friend plans to export almost a tonne of south-east Australian truffles to the UK, US, Japan and other northern hemisphere countries hungry for the winter-ripening fungus.

Friend must ensure that his truffles are perfect before trading on the global market. The co-owner of Friend & Burrell wholesalers sorts through scores of kilograms of truffles, rejecting any with the hint of an insect hole, soft patch, or nibble mark from a rabbit or bandicoot. Any blemish can lead to rot.

"A lot of people talk about the aroma of a truffle but forget that it has to have good flavour," says Friend. "People often think that because a truffle has a powerful aroma, it must be good to eat too. But when they cook with it, the truffle can have no flavour. However, a truffle with a subtle nose can sometimes taste tremendous."

Truffles contain a high percentage of glutamic acid, the amino acid taste buds detect as being delicious. When the glutamic acid of a truffle meets umami-rich ingredients such as parmesan cheese, scallops, foie gras and other fungi, the black tuber comes into its own, says Wilkinson.

"Other foods, especially dairy, make truffles shine," he says. Wilkinson believes Australia now produces some of the best black truffles in the world.

"Their price may be around $3000 a kilogram, but you only need 35 grams shared between several people and it becomes an affordable luxury – especially for diners eager to treat themselves after a little period of unplanned confinement."

Where to get a winter truffle fix in Melbourne

Truffle Melbourne, Queen Victoria Market

Queen Vic's free two-day truffle festival begins July 10 with cooking demonstrations, truffle Bloody Marys, and plenty of opportunities to buy the black diamonds for home use.

Truffle Celebration, Prahran Market

A progressive truffle crawl around Prahran Market on Saturday July 24 featuring dishes such as truffle, veal and mushroom sausage from Gary's Meats, and truffled buckwheat polenta with taleggio and honey from The Essential Ingredient. Tickets from $35.50.

Bellota, South Melbourne

Chef Nicky Reimer is well known for her warming winter pine mushroom ragout, served on butter and parmesan-enriched polenta and cloaked in shaved truffles for $35.

Omnia Bistro, South Yarra

Make a reservation for chef Stephen Nairn's $35 truffle tart: a buttery brisee pastry base topped with luscious pine mushroom custard and a mosaic of truffle slices.

Tipo 00, CBD

$20 will buy you a truffle misu from chef Andreas Papadakis, whereby a hollow chocolate brownie is filled with truffle and mascarpone, and soaked with hot salted-caramel coffee.

Red Hill Truffles, Red Hill

Book a truffle hunt from $150 in the green rolling hills of the Mornington Peninsula to work with loyal sniffer dogs and harvest black gold from the earth. Afterwards, taste a dish made with truffles at the farm or head to Max's Restaurant for a Red Hill Truffle three-course lunch and glass of wine.