Scientists unearth secrets of Perigord truffles, the culinary 'black diamond'

Dec 04, 2013
Scientists unearth secrets of Perigord truffles, the culinary 'black diamond'

Just in time for the holidays when cooks in France and elsewhere will be slipping bits of the coveted black Périgord truffle under their turkeys' skin for a luxurious flavor, scientists are revealing the secrets that give the culinary world's "black diamond" its unique, pungent aroma. Their study, which could lead to better ways to determine the freshness and authenticity of the pricey delicacy, appears in ACS' Journal of Proteome Research.

Mark Baker, Shoba Ranganathan and colleagues note that the harvest of the Périgord , a fungus that grows underground around the roots of oak and hazelnut trees in winter, has plummeted recently due to climate change, the loss of arable land and the cultivation of lower-quality truffles. Paired with an increase in demand from "foodies" seeking exotic flavors, prices for this truffle have skyrocketed 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.

Explore further: Gap closed in the genetic map of kingdom fungi

More information: Unlocking the Puzzling Biology of the Black Périgord Truffle Tuber melanosporum, J. Proteome Res., Article ASAP. DOI: 10.1021/pr400650c

Abstract
The black Périgord truffle (Tuber melanosporum Vittad.) is a highly prized food today, with its unique scent (i.e., perfume) and texture. Despite these attributes, it remains relatively poorly studied, lacking "omics" information to characterize its biology and biochemistry, especially changes associated with freshness and the proteins/metabolites responsible for its organoleptic properties. In this study, we have functionally annotated the truffle proteome from the 2010 T. melanosporum genome comprising 12 771 putative nonredundant proteins. Using sequential BLAST search strategies, we identified homologues for 2587 proteins with 2486 (96.0%) fungal homologues (available from biolinfo.org/protannotator/blacktruffle.php). A combined 1D PAGE and high-accuracy LC–MS/MS proteomic study was employed to validate the results of the functional annotation and identified 836 (6.5%) proteins, of which 47.5% (i.e., 397) were present in our bioinformatics studies. Our study, functionally annotating 6487 black Périgord truffle proteins and confirming 836 by proteomic experiments, is by far the most comprehensive study to date contributing significantly to the scientific community. This study has resulted in the functional characterization of novel proteins to increase our biological understanding of this organism and to uncover potential biomarkers of authenticity, freshness, and perfume maturation.

add to favorites email to friend print save as pdf

Related Stories

New species of truffle found in Finland

May 16, 2013

A species of truffle that is considered to be rare has been found for the first time in Finland. Previously it has been thought to exist only in the Pacific Northwest region of the United States. The truffle ...

Scientists scent breakthrough in truffle trafficking

Mar 28, 2010

One of Europe's gastronomic jewels, the fabled black Perigord truffle, has been genetically unravelled, a feat that could doom fakers who pass off inferior truffles as the real thing, scientists said on Sunday.

Gap closed in the genetic map of kingdom fungi

Sep 20, 2013

An international research team headed by PD Dr Minou Nowrousian from the Ruhr-Universität Bochum (RUB) has sequenced the genome of the ascomycete Pyronema confluens, thus closing a gap in the genetic map ...

Scientists reveal the sex wars of the truffle grounds

Oct 25, 2010

They are one of the most highly prized delicacies in the culinary world, but now scientists have discovered that black truffles are locked in a gender war for reproduction. The research, published in New Ph ...

Recommended for you

The microbes make the sake brewery

Jul 24, 2014

A sake brewery has its own microbial terroir, meaning the microbial populations found on surfaces in the facility resemble those found in the product, creating the final flavor according to research published ahead of print ...

User comments : 0