Amino acids, fatty acids, and organic acids critically shape shrimp paste flavor, serving as taste compounds and aroma precursors. However, their simultaneous analysis remains challenging. In this study, a silylation derivatization method combined with GC-MS was established for simultaneous quantification of these compounds. The method exhibited high sensitivity, with LODs ranging from 0.26-5.02 μg/g for amino acids, 0.26-3.86 μg/g for fatty acids, and 0.92-1.96 μg/g for organic acids, along with satisfactory accuracy reflected in spike recoveries of 81.2-108.8. This method was employed to investigate the acid profiles of sour shrimp paste (SSP) and its differences from conventional shrimp paste (CSP). SSP demonstrates a markedly higher lactic acid concentration (660.75 μg/g, ten times that of CSP at 75.16 μg/g), an approximately fivefold greater content of fatty acid esters, and a unique free fatty acid profile. The established method serves as a powerful tool for the comprehensive assessment of acid profiles in shrimp paste, providing a solid methodological reference for analyzing its flavor-metabolic precursors. • A method for simultaneous quantification of acids in shrimp paste is established • High accuracy and precision are achieved with internal standard correction • Sour shrimp paste has higher lactic acid and richer fatty acid esters • Expanded GC-MS analysis scope from volatiles to acid precursors in shrimp paste
Yang et al. (Wed,) studied this question.