Integrated taxonomic characterization, postharvest quality evolution, and sustainable conservation of truffle species from Calabria (Southern Italy)

Truffles are fungi, usually globular and found underground, typically located using trained dogs. The most consumed species belong to the genera Tuber, Terfezia, and Tirmania. Southern Italy produces both black and white truffles. Truffles are characterized by a short shelf life due to the loss of quality as a consequence of microbial spoilage and enzymatic browning. This work aimed at the taxonomic identification, by using a molecular approach, of three truffle species, such as Tuber mesentericum Vittad. (TM), Tuber borchii Vittad. (TB), and Tuber aestivum var. uncinatum Chatin (TU), collected from the Calabria region and the evolution of truffle's quality parameters for 28 days in two storage conditions (under rice and vacuum). The total phenols content (TPC) and total flavonoids content (TFC), degradation kinetics, as well as antioxidant activity were also assessed. Generally, the vacuum packaging proved to be more effective in maintaining the sensory and nutritional quality of TB and TU, whereas the results for TM were more variable, showing greater sensitivity to microbial proliferation under anaerobic conditions. Kinetics results evidenced that the degradation of both TPC and TFC does not depend on the different preservation methods but on the species of truffle object of investigation. Principal Component Analysis does not allow us to establish the advantage of the vacuum preservation method compared to that under rice. Therefore, the use of rice as a matrix to be recovered at the end of the preservation process, edible and rich in truffle aroma, can represent an interesting aspect for the consumer.