TRUFFLES V - OH ! WHAT MAGNIFICENT ODOURS !

Tuber magnatum pico

 Like hundreds of other mushroom species, truffles grow underground (hypogeous). While this adaptation bestows some benefits, like protection from bad weather, it prevents the truffles from dispersing their spores by wind. Instead, truffles have evolved mechanisms that enlist the help of animals. Attracted by the truffle’s complex odours, the animals dig the truffles up and in doing so, disperse their spores. These aromas are what make certain truffle species so highly sought after by chefs and gourmands around the world.

Words often fail us when we try to define new aromas. We fall back to using comparisons to those odours we know best, like rose or garlic. Neurologist Annick Faurion, renowned for her work on taste perception, stressed during her recent visit to Montreal that such analogies are inadequate because they ignore the complexity and uniqueness of all odours. For example, the truffles harvested this November outside of Montreal by our friend Richard Charette had a very agreeable aroma, nearing that of other North American Lyonii truffles but unique in its own right.

Odours differ greatly from one species to the next and even within the same species, depending on the location. White Alba truffles, for instance, are characterized by a few typical smells: odours of garlic, musk, and cheese often come to mind. Now thanks to laboratory analyses, it is even possible to pinpoint the village where a specimen was harvested based on its aromatic profile.

The Chemistry Behind Aromas

Differences in smell within a species can be significant. For example, the Melanosporum truffles of Perigord are more prized than their central Italian counterparts because of their odour (please see table for the aromatic profile). However, without the appropriate tools, the nuances of their individual aromatic formulas might escape us.

In the laboratory, we can determine the exact makeup of an aroma. Those of us who can survive professional jargon will remember that Dimethyl sulfide dominates the odour of Alba’s Magnatum pico, so much so that it is often synthetically added to lower grade truffle products to give an air of authenticity. However, the actual odour contains many more molecules in varying proportions, each with their own perception threshold. For instance, some molecules can be perceived even at infinitesimal concentrations.

This may not seem very appealing, but molecules similar to butane and propane are found in the odour of Melanosporum truffles from Central Italy. The first inhalations are surprising, as surprising as the sensation of drinking beer for the first time.

Not all truffles have desirable aromas and not all desirable aromas are for everyone. Everyone will agree that valued species like the White Alba produces intense smells: adding one specimen to an egg carton is usually enough to infuse all of the eggs with its fragrance.

Companies are well on their way to mastering the synthetic chemistry and gastronomic rhetoric necessary to successfully produce and market their gourmet products. No longer can you just read the list of ingredients: you must be familiar with the codes that are used. Every word is carefully chosen, and its position meticulously planned.

Even if chemically synthesized, the smell of any truffle is bound to make an impression and more often than not, the aroma is undeniably addictive.