“…According to metabolomic data, of the three goat meat samples (0, ε-polylysine, sodium dehydroacetate), the one with the additive had higher levels of various amino acids ( l -tyrosine, l -phenylalanine, l -valine, and l -isoleucine). l -Valine (0.22, 0.33, and 0.30 mg kg –1 ) is an amino acid required by the body for growth, maintenance, and repair, and l -isoleucine (1.44, 2.04, and 1.86 mg kg –1 ) is an essential hydrophobic branched-chain amino acid, both of which possess nonpolar side chains . In preservative-added goat meat, l -tyrosine is synthesized in the body from l -phenylalanine by the action of phenylalanine hydroxylase (PAH) in the liver, the enzyme responsible for converting the phenyl ring in the side chain.…”