Truffles are a secretive underground crop that take time to develop, but when a ripe one is harvested, its aroma lingers - a little like the New Zealand truffle industry itself, which is celebrating 20 years. Charmian Smith talks to Dr Ian Hall, who started it all.
There's still a lot of folklore associated with truffles, those secretive underground fungi that command thousands of dollars a kilogram, says Dr Ian Hall. He is co-author, with Gordon Brown, and Alessandra Zambonelli, of Italy, of Taming the Truffle: The history, lore and science of the ultimate mushroom.
Published to celebrate 20 years of the industry in New Zealand and as much a growers' guide as a scientific and social background to the subject, it's the most comprehensive book on the subject, he claims modestly, but he has spent most of his career studying the elusive fungi.
It is 30 years since he first thought about researching truffle production, 20 since the first Perigord truffle-inoculated seedlings were produced, and this year the first bianchetto truffles, little whitish Italian truffles, have been harvested in New Zealand, he says.
The idea of growing the highly valued Perigord black truffles commercially started in 1979, when he was at a conference in Illinois and overheard a couple of French people having lunch at a nearby table. They were talking about the first truffles harvested from their special plantations,
Dr Hall said.
At the time the young mycologist working at a government research institute was considering various research options.
"I could have researched the production of extremely toxic chemicals from fungi that grow on grasses - it was an option and might have been financially more lucrative, but the idea didn't appeal. There would probably have been funding but maybe not from New Zealand sources. The third option was producing medicines from fungi,'' he said.
However, it was the production of the Perigord black truffles that fascinated him. They are highly sought-after in Europe, their provenance kept secret, and they are often adulterated with truffles of lesser value. His idea was that New Zealand truffles should be exported to the lucrative European market out of the northern hemisphere season, although it took five years to find funding.
He would like to have gone to France and Italy, but funding allowed only for truffles to be sent from Europe, which was traumatic, as they were often rotting by the time they arrived. Fresh truffles were needed because it was easiest to use broken-up truffle to inoculate the roots of oak and hazelnut trees, he said.
It was a line in a letter from a Frenchman that gave the game away about how it was done, but the process is still his trade secret.
The first inoculated trees were planted in North Otago and the Otago Daily Times wrote a story about it. He had 600 letters and telephone inquiries so he started producing the inoculated trees commercially - that was in 1988, he said. The first truffles were found in 1993 at the truffiere of Dr Hall's brother, Alan Hall, in Gisborne, five years after planting.
In 1989 a "spy'' from France came to investigate and offered $200 a kg, he said. Now the price in Europe is about $3500 a kg, pushed up by scarcity because production there has dropped remarkably. The changing weather pattern in Europe - hotter and drier summers will not be helping, he said.
"You get all sorts of strange information coming out of Europe, because when they don't know what the answer is, there's a tendency to go back to folklore or wild guesswork. The French would say it grows in very dry areas, therefore it needs dry conditions, which it may do, but it doesn't need dry conditions to prove it. You must have moisture.''
Now there are more than 100 truffieres around the country producing truffles, and last year the total harvest was thought to be about 100kg. However, the three truffieres in North Otago have not produced any, something he puts down to lack of water.
"The truffles will be still there. They can survive deep down for years, and if the moisture level comes back up they will come. If you irrigate, you have to keep watering every year but if you over-water you acidify the ground and turn it into a smelly mess. Water plays a huge part,'' he said.
Originally, Dr Hall expected all the truffles would be exported, but now they are all sold to a handful of fine-dining restaurants in New Zealand.
The first truffles were produced in 1997 and the following year his research funding was cut off - the idea was that if it's commercial, the market would provide, but that didn't happen, he said.
"When I was first employed I was a state servant and my role was to do research for good of my adopted country. I established the truffle industry for the good of country, not individuals. Many bits of research are done that might take 20 years to come of age, just like truffles, you don't get an immediate pay-off.''
He left Crop and Food at Invermay four years ago and is involved in consulting, research and producing inoculated trees.
They make a good retirement project as they do not need a large area of land, they are easily looked after and the potential returns are high, he says.
However, it usually takes between five and 15 years after planting the trees for them to produce truffles and in that time people can get bored. There is potential for disaster if disease strikes the oaks or hazelnuts, and he recommends planting both species. A high-pH soil such as limestone is needed and water or irrigation is important.
"Like any mushroom, truffles grow quickly. When the rains come in January or February the truffle expands and you see the ground lifting like a volcano. You can mark the place, and months later, when the truffles have ripened, you can take your truffle-hunting dog to see if they are ripe,'' he said.
There are many different sorts of truffles, with various flavours and value, and Dr Hall foresees several different types being grown in New Zealand: the Perigord black harvested between May and August; the Bianchetto between July and the end of October; and the summer Burgundy truffle that grows in cooler climates, harvested between February and May, would give a local supply for nine months of the year, he says.
