Amino Acids (Free and Hydrolyzed)

Abstract

AbstractAmino acids are an important compound since they form part of the proteins and are intermediates in the metabolism. Some amino acids are synthesized by the organism, however, in other cases, they should be ingested in the diet (essential amino acids). Because of the high content of amino acids in meat and meat products and their influence on the nutritional and sensorial quality, it is necessary the validation of new techniques to be more sensitive, faster, and versatile for the determination of both free and hydrolyzed amino acids. Despite that there are published several techniques for amino acids extraction, derivatization and for identification/quantification, it should be mentioned that some of them present certain limitations.The present chapter gives a clear and complete vision of a procedure for the free and hydrolyzed amino acids analysis in meat and meat products. Free amino acid extraction includes the following steps: homogenization and extraction from the meat matrix, deproteinization, derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate, and subsequent analysis by liquid chromatography with fluorescence detection (HPLC-FL). Hydrolyzed amino acids are determinate in the following manner: first, the hydrolysis step during 24 h at 110 °C and then the derivatization step with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate prior to chromatographic analysis by HPLC-FL. All steps are described in detail so that the conditions proposed by us can be reproduced by other researchers.Key words Food analysis Free amino acids Hydrolyzed amino acidsDerivatization Liquid chromatography