Enrichment of the umami‐taste‐active amino acids and peptides from crab sauce using ethanol precipitation and anion‐exchange resin

The umami-taste-active amino acids and peptides in crab sauce were isolated by ethanol precipitation and anion-exchange resin, and then identified by amino acid analyzer, MALDI-TOF-MS, and taste sensing system. The total free amino acids content increased 6.2 times after the treatment, and Glu and Asp were the dominated free amino acid, which accounted for about 60% of the total free amino acids. The peptides content increased 2.2 times, and five peptides, Glu-Arg, Asp-Pro-Cys, Asp-Val-Cys, Asp-Val-Asp, and Trp-Phe, were identified by MALDI-TOF-MS. The taste information tested by taste sensing system showed umami taste was enhanced after the treatments, which was well correlated with the results of free amino acids and salt content. The results showed that ethanol precipitation, followed by anion-exchange resin, was an efficient method for the enrichment of the umami-taste-active amino acids and peptides, and taste sensing system was a simple and reliable tool for discrimination the taste information. Practical applications This research describes a potential processing method for enriching of the umami-taste-active amino acids and peptides from sauce by the combination of ethanol precipitation and anion-exchange resin. And taste sensing system was a simple and reliable tool for discrimination the taste information as it was well agreed with the results of free amino acids and salt content.