On June 21, 2017, Lytra, Georgia; Franc, Celine; Cameleyre, Margaux; Barbe, Jean-Christophe published an article.Category: esters-buliding-blocks The title of the article was Study of Substituted Ester Formation in Red Wine by the Development of a New Method for Quantitative Determination and Enantiomeric Separation of Their Corresponding Acids. And the article contained the following:
A new method was developed for quantifying substituted acids including, where applicable, their various unexplored enantiomeric forms. A new step was added to acids’ usual quantification methods, consisting of extraction, derivatization to Me esters, and gas chromatog. anal.: preliminary extraction was performed at basic pH to eliminate Et esters, thus avoiding their transesterification during derivatization. Quantitation and enantiomeric distribution of some substituted esters and their corresponding acids were established in 31 com. Bordeaux red wines from 0 to 20 years old. A strong pos. correlation was observed between the age of wine and levels of Et 2-methylpropanoate, Et 3-methylbutanoate, Et 2-methylbutanoate, Et (3R)-3-hydroxybutanoate, both enantiomeric forms of Et 2-hydroxy-3-methylbutanoate, and Et (2S)-2-hydroxy-4-methylpentanoate, but not Et (3S)-3-hydroxybutanoate. However, the standard deviations of average concentrations for the corresponding substituted acids were so large that only few correlations between concentrations and age were observed Concentrations of (2S)-2-hydroxy-3-methylbutanoic acid and (2S)-2-hydroxy-4-methylpentanoic acid increased slightly over time, while (2R)-2-hydroxy-4-methylpentanoic acid levels decreased slightly with the age. Variations in the ratio of substituted Et esters to their corresponding acids over time detected thanks to these anal. advances suggested that, in general, acids were continuously esterified during aging. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Category: esters-buliding-blocks
The Article related to alkyl acid ester enantiomer red wine extraction gc, chiral substituted acids, chiral substituted esters, enantiomeric distribution, Food and Feed Chemistry: Analysis and other aspects.Category: esters-buliding-blocks
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics