RESUMO
The 4-mercapto-4-methylpentan-2-one (4MMP) is a key aroma compound in wines, especially in Sauvignon Blanc ones. Its accurate quantification is quite difficult due to its traces levels and its reactivity in wine conferred by the thiol function. In this paper, we proposed a new method for its quantification in wine without any sample preparation, based on automated derivatization procedure by methoximation and SIDA-SPME-GC-MS/MS analysis. The derivatization procedure was adapted from a previously published method in order to decrease the amount of reagents and the volume of wine (only 3mL are required). The use of SPME and the detection conditions have also been optimized to reach the best sensitivity as possible. The method was then validated according to the International Organization of Vine and Wine recommendations and exhibited excellent performances. Indeed, this method allowed us to quantify the 4MMP in wine at traces levels (LOD=0.19 ng L(-1)) with reproducible results (RSD<15%) and a very good accuracy (recovery=102%).
Assuntos
Odorantes/análise , Pentanonas/análise , Compostos de Sulfidrila/análise , Espectrometria de Massas em Tandem/métodos , Vinho/análise , Desenho de Equipamento , Cromatografia Gasosa-Espectrometria de Massas/métodos , Técnicas de Diluição do Indicador , Isótopos/análise , Limite de Detecção , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Vitis/químicaRESUMO
Due to its toxicity and presence in numerous food products, Ochratoxin A (OTA) has drawn attention for decades. This article summarizes the first synthesis of a labeled analogue of Ochratoxin α (OTα), one of the main products generated by the metabolization of OTA by microorganisms. This synthesis also led to a new labeled analogue of OTA with the deuteration located on the dihydroisocoumarin moiety allowing thus both the accurate quantification of OTA and OTα and the establishing of a reliable detoxification rate.