Naturally functional: Truffles have functional ingredient potential...but work needed on productivity

Often referred to as ‘underground gold’ or a ‘diamond in the kitchen’ by chefs and critics, the truffle is an important gourmet culinary ingredient used by top restaurants and kitchens. However, the expensive delicacy also has great potential as a healthy and functional ingredient, according to a team of international researchers.

Writing in Trends in Food Science & Technology, ​the team noted that while their current low productivity makes them expensive and inaccessible to the majority of the world's population, if this can be changed then truffles have a great deal of potential as a functional food.

“Their nutritional and gustatory value is already of immense repute,” ​noted the team – led by first author Seema Patel from the Bioinformatics and Medical Informatics Research Center, San Diego State University. “As it is nutrition-rich, with no known side effects, and is a great addition to diet, efforts should be directed to prospect edible varieties of truffles (beyond Europe and Pacific North West), and to enhance their productivity.”​

Nutritional value​

According to the team, truffles contain naturally high levels of protein, amino acids, and essential minerals and sterols that make it a perfect candidate as a functional ingredient.

“Truffles are rich in protein, fat, dietary fibre, ash, essential amino acids (methionine, phenylalanine, valine, serine, isoleucine and threonine), and metals (K, P, Fe, Cu, Zn and Mn),”​ wrote the team. “For example, chemical analysis of desert truffles showed that protein constitutes 20–27% of the dry matter.”​

Furthermore, truffles contain a combination of potentially beneficial volatile organic compounds (VOCs) including aldehydes, alcohols, ketones, and organic acids (ascorbic acid) in various ratios, they said.

“Recent studies have proven that some truffles have ergosteroids, the most widespread fungal sterol, that can be transformed into vitamin D in the human body,”​ said Patel and colleagues.

“With the identification of its components such as ergosterol, tuberoside anandamide, polysaccharides, and phenolics, as well as the validation of nutritional benefits as antioxidant, anti-inflammatory, immunomodulatory, antitumor, antimicrobial, and aphrodisiac, it is attracting international consumer attention,” ​they added.

Supply and demand​

However, the consumer base for truffles meagre, said the team.

“It is their low productivity that makes them expensive and inaccessible to the majority of the world's population,”​ they noted – adding that global production of truffles is hundreds of tonnes, “which is insufficient.”​

“Due to the stark mismatch between supply and demand, the cost can surge to US $5000 per kilogram of white truffles (other types can be much cheaper, especially desert truffles),”​ they said.

However, Patel and colleagues suggested that if the global truffles yield can be improved, their cost will drop.  

The team noted that while truffle plantations are being established, they are ‘riddled with a variety of challenges.’

“Integrative approaches, including artificial inoculation and fermentation, can materialize this objective,”​ they said. “An integrated approach of omics, ecological optimization, fermentation, and preservation can contribute in this direction.”​

Source: Trends in Food Science & Technology​

Volume 70, December 2017, Pages 1-8, doi: 10.1016/j.tifs.2017.09.009​
“Potential health benefits of natural products derived from truffles: A review”​
Authors: Seema Patel, et al​