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Chiral MEKC‐LIF of amino acids in foods: Analysis of vinegars
Author(s) -
Carlavilla Davinia,
MorenoArribas M. Victoria,
Fanali Salvatore,
Cifuentes Alejandro
Publication year - 2006
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.200500909
Subject(s) - chemistry , amino acid , autolysis (biology) , chromatography , fermentation , wine , aspartic acid , methionine , alanine , proline , organic chemistry , enzyme , biochemistry , food science
The formation of D ‐amino acids ( D ‐aa's) in many fermented foods depends, among other factors, on the particular fermentation conditions, the action and autolysis of the microorganisms involved. In this sense, the analysis of chiral amino acids is an interesting analytical strategy for food scientists, since these compounds can be used as bacterial markers and can help, e.g. , to detect adulterations, microbiological contaminations, etc. In this work, a fast and sensitive method based on MEKC‐LIF has been developed to analyze and quantitate L ‐amino acid ( L ‐aa) and D ‐aa in vinegars. The chiral MEKC‐LIF procedure uses 100 mM sodium tetraborate, 30 mM SDS, and 20 mM β‐CD at pH 9.7 as running buffer, obtaining a good separation of the main vinegar L ‐/ D ‐aa previously derivatized with fluorescein isothiocianate. Namely, L / D proline, alanine, arginine, glutamic, and aspartic acid, plus the nonchiral amino acid γ‐aminobutyric acid are separated in less than 20 min with high efficiency (up to 720 000 plates/m) and good sensitivity (LODs lower than 16.6 nM were achieved). Several D ‐aa's were detected and quantified in balsamic, sherry, white wine, and cider vinegars using this MEKC‐LIF procedure, observing interesting differences in their L ‐aa and D ‐aa profiles and contents.