50 Years of Mass Spectrometry at Firmenich: A Continuing Love Story

Abstract

Mass spectrometry (MS) has been intensively used in the field of flavor and fragrance since its beginning in the 1950s, and it remains an essential technique for current and future research in this field. After a short historical section on the introduction and development of MS at Firmenich, this work reviews the main applications of MS-based techniques published by Firmenich researchers over the past 5 years. It exemplifies the use of gas chromatography (GC)-MS for the discovery of new odorant - hence volatile - molecules in a broad range of natural products, such as fruits, meats, and vegetables. Non-volatile compounds play a major role in taste attributes and are also possible precursors of odorant molecules. Their identification by liquid chromatography (LC)-MS in the context of malodor generation from sweat is a typical example of such a relationship. With their high selectivity and sensitivity, GC-MS and LC-MS instruments are used in the fields of flavor and fragrance not only for identification, but also as unique tools for the accurate quantitation of compounds in complex matrices. This is particularly important for regulatory analyses such as dosage of potential allergens in perfumes and for the development of delivery systems. Finally, because of the rapid response time of MS, the kinetics of processes such as the release of flavors in the mouth during food consumption can be monitored by direct sampling into the mass spectrometer.

Identification and Quantitation of New Glutamic Acid Derivatives in Soy Sauce by UPLC/MS/MS

“…It should be mediated by an enzyme, since only l-lactyl-l-amino acids were found in cheese [20]. In our work, the synthetic product Lac-Glu (8), synthesized from l-lactic acid and l-glutamic acid ester [19], contained a small amount of a minor diastereoisomer, likely d-Lac-l-Glu. We verified that this diastereoisomer was not present in soy sauce.…”

“…The synthesis of Suc-Glu (6) and its spectral data were described by Frerot and Benzi [12]. The synthesis of l-Lac-Glu (8) and l-Lac-Leu (20), and their spectral data were described by Frerot and Escher [19].…”

“…The two products 1 and 5, as well as N-succinoylglutamic acid (6) [12], could not be identified by the first full-scan experiments using the ion-trap MS, but were detected by the TOF-MS. Their occurrence in soy sauce was firmly established by determining the MS transition ratios in the selected reaction monitoring mode (SRM), using the triple quadrupole mass spectrometer. The ratio of the peak area corresponding to two transitions was determined at different concentrations for the synthetic products.…”

“…Chemically synthesized succinoyl amino acids such as N-succinyl glutamate were also found to be taste-active [12], but were never reported to occur in foods.…”

“…g-Glutamyl dipeptides are ubiquitous compounds in foods [8] [9] [16] [17]. Lactoyl amino acids were first discovered by Firmenich during the analysis of Parmesan [18] and patented for their taste properties [19]. A thorough study of Parmesan and other Italian cheeses revealed that pyroglutamyl dipeptides, lactyl amino acids, and g-glutamyl dipeptides accumulated during ripening, probably because they could no longer be recognized by hydrolytic enzymes [20].…”