Description of the analyte: The term “amino acids” refers (primarily) to L- 煦 -amino acids of the general structure (except proline):
specifically, the twenty common proteinogenic amino acids. Amino acids may be present either in their free forms or bound, as part of the protein/peptide component. Although cysteine is listed in the table, as it fits the general structure for 煦 - amino acids, its disulfide form, cystine, is obviously included in the working definition of amino acids. The two are equivalent from a nutrition point of view and regulations treat them as such. Because of method overlap, taurine (2-amino-ethanesulfonic acid) is also included in this analyte category, despite not fitting the basic definition.