The black Périgord truffle is a fungus that grows underground around the roots of oak and hazelnut trees in winter. It has become a staple during holidays in France, where cooks slip bits of it under the skin of roasting turkeys to add a luxurious flavor.

Holiday cooking would not be complete with an examination of why things work and so scientists are revealing the secrets that give the culinary world's "black diamond" its unique, pungent aroma. The results could  also lead to better ways to determine the freshness and authenticity of the pricey delicacy. 

Mark Baker, Shoba Ranganathan and colleagues note that limited supply paired with an increase in demand from "foodies" seeking exotic flavors have caused prices for this truffle to skyrocket to more than $900 per pound.

Though long celebrated in the kitchen, only recently has the black Périgord truffle garnered scientific attention. In 2010, European scientists published the full genome of the Périgord, but this raw blueprint remained largely un-mined. In their report, Baker and Ranganathan's team go beyond the genetic code to identify and describe the truffle's proteins for a better understanding of the culinary delight. 

By marrying techniques in bioinformatics and proteomics, they combed databases to unearth what proteins make the black Périgord truffle, which they obtained from the Marshalls' Terra Preta truffière in Braidwood, New South Wales, unique.

They found that more than 2,500 proteins out of the truffle's nearly 13,000 were similar to existing proteins in other fungi, and they identified nine proteins that contribute to the cherished aroma.

"This study has resulted in the functional characterization of novel proteins to increase our biological understanding of this organism and uncovered biomarkers of authenticity, freshness and perfume maturation," the scientists state.