Not only the quantitative composition, also the optical purity of the amino acids are determined. The quantitative amino acid analysis is done by Enantiomerlabeling: By capillary gas chromatography on a chiral stationary phase it is possible to separate the amino acids together with their enantiomers, thus allows the determination of enantiomeric purity after hydrolysis. In a second analytical run the sample is spiked with an aliquot of the optical antipodes of the amino acids and d-norvaline as standard for glycine. These serve as ideal multi internal standards, which are calibrated against certified standards from National Institute of Standards and Technology (NIST).

Results: Enantiomeric purity after! Hydrolysis ( = blind values ) Content of amino acids (mg/g, umol/g) Residues of amino acids Peptide content.

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