# Comparative analysis of the non-volatile metabolites and taste profiles of the four famous freshwater fish raw materials in China

## TL;DR

This study compares the taste and non-volatile metabolites of four popular Chinese freshwater fish to understand their distinct flavor profiles.

## Contribution

The research identifies key metabolites and taste compounds that differentiate the flavor profiles of four freshwater fish species.

## Key findings

- Mylopharyngodon piceus had the highest levels of free amino acids and ATP compared to other species.
- Ctenopharyngodon idella and Mylopharyngodon piceus showed richer taste profiles than the other two species.
- 49 key metabolites were identified, mainly from lipid, amino acid, and organic acid metabolism pathways.

## Abstract

Four famous freshwater fish in China are renowned for their high production among freshwater species and are much-prized as sought-after delicacies. However, the distinct taste profiles and the specific associated taste substance of these carps remain poorly understood. This study primarily investigated the taste profiles and associated taste compounds, along with non- volatile metabolites of these four species using ultra performance liquid chromatography-mass spectrometry (UPLC-MS) combined with electronic tongue technology. Results revealed that Mylopharyngodon piceus (MP) exhibited significantly higher levels of total free amino acids and adenosine triphosphate (ATP) compared to the other three fish species (p < 0.05), with contents reaching approximately 388.90 mg/100 g and 140.88 mg/100 g, respectively. Ctenopharyngodon idella (CI) and MP possessed richer tastes compared to Aristichthys nobilis (AN) and Hypophthalmichthys molitrix (HM) based on the electronic tongue analysis. Furthermore, UPLC-MS metabolomics analysis identified 49 key metabolites, highlighting major metabolic pathways including lipid, amino acid, and organic acid metabolism. The findings suggested that variations in taste-related compounds and metabolites within metabolic pathways contribute to the distinct flavor profiles observed among the four famous fish species. This research offers essential insights for aquaculture professionals and researchers focused on enhancing the flavor quality of these key fish species, especially in understanding the regulatory mechanisms involved in flavor development

Unlabelled Image

•UPLC-MS analysis identified 49 key metabolites in the four famous freshwater fish.•Key metabolites in four fish species are mainly derived from the pathways of free amino acid metabolism, lipid metabolism and amino acid metabolism.•Ctenopharyngodon idella (CI) and Mylopharyngodon piceus (MP) potentially possessed more pronounced taste flavors than Aristichthys nobilis (AN) and Hypophthalmichthys molitrix (HM).•MP display the highest content of the total free amino acid at 388.90 mg/100 g.

UPLC-MS analysis identified 49 key metabolites in the four famous freshwater fish.

Key metabolites in four fish species are mainly derived from the pathways of free amino acid metabolism, lipid metabolism and amino acid metabolism.

Ctenopharyngodon idella (CI) and Mylopharyngodon piceus (MP) potentially possessed more pronounced taste flavors than Aristichthys nobilis (AN) and Hypophthalmichthys molitrix (HM).

MP display the highest content of the total free amino acid at 388.90 mg/100 g.