CHEMICAL CHARACTERIZATION OF WHITE ACQUALAGNA TRUFFLE (TUBER MAGNATUM PICO) BY UHPLC-QTOF-MS, GC-MS, ICP-MS AND SENSORY ANALYSIS.

White Truffle is the most expensive edible hypogeous fungi that grow in symbiosis with the roots of the host plants, and it is appreciated for its extraordinary taste and smell. Global demand for truffles has increased significantly in recent years, and the requirement for traceability of truffle origin has become an important aspect of the truffle trade. Therefore consumers are interested in regional and authentic food products and the specification of the geographical origin of the European truffles is particularly relevant [1]. Considering the scarce scientific literature, this work represents the first study with the characterization of the Acqualagna white truffle. A new untargeted metabolomics approach, using UHPLC-Q-TOF allowed us to identify 456 potential metabolites. Analysis were performed both in positive and in negative polarity acquisition modes and mass spectra were processed using MS-DIAL, which provides information about mass accuracy, isotopic pattern, and spectral matching with the library of each compound. More than 60 compounds reported a total identification score match greater than 90%. Moreover, the elemental composition was investigated through ICP-MS and revealed a higher content of K, P, S, Ca and Mg, representing 97% of the elements investigated. The correspondence between the elements present in the water released from the soil and in the truffle was also taken into consideration to detect which elements of the soil have been assimilated. The aroma profile of fresh truffles was performed using the gas chromatography-mass spectrometry system (GC-MS) and was compared with the sensorial analysis. The results of the volatile profile consist mainly of Bis(methylthio)methane (78.72%) and other 50 minor constituents. This study identified for the first time the natural mixture of key odorants and showed the correspondence between odorants and molecules of the white Acqualagana truffle. In conclusion, this is the first step to characterize and determine the origin traceability of the Acqualagna white truffle, a local food defined by its unique composition.