Albert Vieille SAS

Pure and natural essential oils of Allium species are primarily used in the food industry, but due to their low yield, production quantities can be difficult to achieve and thus can be highly expensive.Due to these problems, adulterations are a reality in this field.The purpose of this research is to develop a multi element stable isotope anal. methodol. for authentication of the essential oils of leek, onion, shallot, and chive.Naturalness of these essential oils was achieved by assessment of compound specific δ13C and δ34S: an addition of 5% of synthetic compound can be detected.Chemometric models were undertaken to assess purity by distinction of the Allium samples according to their species origin using bulk stable and compound specific δ13C, δ2H, δ34S, and compositions of their major metabolites di-Pr disulfide, di-Pr trisulfide, Me Pr disulfide, and Me Pr trisulfide.

The purpose of this work was to develop a methodol. to authenticate the essential oil of wintergreen.Wintergreen essential oil is composed of more than 99% Me salicylate.This aromatic ester can be easily synthesized and used to adulterate wintergreen essential oil.Authentic wintergreen essential oil can be distinguished from adulterated oils by examining their compositionsThe detection of Me salicylate synthetic marker compounds (Me 4-hydroxybenzoate, di-Me 4-hydroxyisophthalate or di-Me 2-hydroxyisophthalate) or the absence of several naturally occurring minor secondary metabolites (Et salicylate and vitispirane) contribute to the authentication.Isotopic values of bulk wintergreen essential oil have also been determined using an isotope ratio mass spectrometer (IRMS): the δ¹³C values of authentic samples range from -36.78 to -33.36‰, the δ²H values range from -173 to -115‰ and the δ¹⁸O values range from -1.3 to 5.7‰.However, these anal. methods cannot account for the natural variability in the essential oils.To determine the boundaries of the natural isotopic values, ¹⁴C radioactive isotope activity assessment was undertaken, which allows for the determination of the genuineness of samples that are not assessed using multistable isotope approaches.Addnl. studies evaluating ¹⁴C activity of a noncompliant sample using IRMS identified a ¹⁴C-labeled synthetic Me salicylate adulteration.

Stable and radioactive isotopes are commonly used in order to authenticate the naturalness and the purity of natural components, such as essential oils.Two studies are exposed in this article.The first one is focused on the development of isotope ratio mass spectrometry (IRMS) and radiocarbon assessment techniques to authenticate the naturalness of wintergreen essential oil. δ¹³C, δ²H and δ¹⁸O isotopic values can highlight a synthetic Me salicylate addition in the essential oil.A second study was carried out on Allium species essential oils (leek, shallot, onion, and chive).Naturalness, geog. and species differentiations were highlighted using ¹³C and ²H isotopes, as well as ³⁴S.