GC-C-IRMS characterization of synthetic bis(methyl-thio)methane in truffle flavorings

Bis(methyl-thio)methane (BMTM), the molecule which provides "white truffle-like" flavor was characterized by physico-chemical methods. Analysis by GC-C-IRMS of eight samples of synthetic BMTM from various raw material suppliers allowed the investigation of the delta C-13 values. More, ten samples purchased on the Italian flavoring market, declared as synthetic BMTM principal component diluted in olive oil were analyzed by GC-C-IRMS. The results of both sample groups allowed us to define the range of delta C-13 values of synthetic BMTM. We verified if the simple proposed extraction method allows to measure the delta C-13 value of BMTM also identified in seasonings of the Italian market declared on label as "white truffle flavored olive oil". In all twenty samples purchased on the market, the data strictly corresponded with synthetic BMTM as the principal component. Measurements by H-1 NMR made on synthetic BMTM and BMTM extracted from "white truffle-like flavor" confirmed that the adopted extraction method using methanol-d4 determined the isotopic distribution of C-13/C-12 ratio in two characteristic sites of this molecule.