According to a new study from truffle researchers at the University of Florida and Michigan State University, some truffle producers in the eastern United States are accidentally cultivating winter truffles (Tuber brumale), a related species that looks nearly identical but sells for less.
Mycorrhiza is the journal that published the findings.
European black truffles are commercially produced in truffle orchards, which contain trees whose roots have been intentionally colonized by the spores of the desired truffle species—a process known as inoculation—in the United States and around the world.
“Our findings suggest that other truffle producers in the eastern United States may be dealing with the same problem. Genetic testing of spores used for inoculation and seedlings to be planted could assist gardeners in ensuring that they will produce the desired species in the future.”
Ben Lemmond, first author of the study.
According to the findings of the study, the trees in the truffle orchards likely contained winter truffle spores, not the more coveted European black truffle, which is a hallmark of haute cuisine and sells for hundreds of dollars per pound.
The researchers analyzed samples from ten unidentified truffle orchards located in six states in the eastern United States. All but one of the samples were winter truffles, and they did so in collaboration with truffle farmers in North America. After being identified as unusual by truffle collectors, these specimens were sent for analysis.
“Our findings suggest that this problem may also be affecting other truffle producers in the eastern United States.” Ben Lemmond, the study’s first author and a doctoral student studying plant pathology in the UF/IFAS College of Agricultural and Life Sciences, stated, “Genetic testing of spores used for inoculation and seedlings to be planted could help growers ensure they will produce the intended species down the line.”
In fact, the researchers used genetic testing to identify the study specimens because European black truffles and winter truffles share such a striking resemblance.
The colder time of year truffle, or Tuber brumale, has a similar dark, finished outside and white-veined inside to the European dark truffle, Tuber melanosporum. Although both are sold commercially, their culinary properties and prices differ.
According to Matthew Smith, senior author of the study and associate professor in the UF/IFAS department of plant pathology, “The owners of the truffle orchards in the study reached out to us because they were finding truffles in their orchards that they suspected were not European black truffles, and we confirmed this through DNA barcode sequencing.”
“The owners of the orchard are in charge of what they do next. “They may take additional measures to distinguish the black truffles from the winter truffles,” Smith, who is also the UF Fungal Herbarium curator, explained.
“Removing the trees from the orchard is the only way to get rid of an undesirable truffle species that is already established in the soil. At that point, you would be starting the orchard from scratch. The spores of the winter truffle may still be present in the soil even then, “Smith added.
Lemmond points out that there is still a market for winter truffles, despite the fact that they lack the opulence of European black truffles. Now that a new truffle species from Europe is known to be present in North America, it is especially important to accurately identify the species of truffles sold to chefs and consumers.
“It is essential for people to be aware that the world is home to more than just “black truffles” and “white truffles.” According to Lemmond, “our study shows that even two truffles that may appear similar at first glance may be two species with completely different culinary properties.” There are more than a dozen species of commercially harvested truffles.
The authors of the study say that they are thankful to the truffle growers and collectors who provided the specimens because they help scientists learn more about the biodiversity of truffles in North America, much of which is still unknown.
“We are fortunate to have strong working relationships with truffle growers in North America and the US’s growing truffle industry. Working together provides opportunities for meaningful citizen science and student training, as this study demonstrates, and has tremendous value. Greg Bonito, one of the study’s co-authors and an associate professor in the department of plant, soil, and microbial sciences at Michigan State University, said, “These results also emphasize the importance of quality control and verification of truffle-inoculated seedlings prior to planting, which will benefit individual farmers and the entire truffle industry.”
The study was also co-authored by undergraduate researcher Alassane Sow at Michigan State University.
More information: Benjamin Lemmond et al, Accidental cultivation of the European truffle Tuber brumale in North American truffle orchards, Mycorrhiza (2023). DOI: 10.1007/s00572-023-01114-8
