Improving the flavor of tilapia fish head soup by adding lipid oxidation products and cysteine.

• More umami and sweet, and less bitter AAs generated by oxidized lipids and cysteine. • Six unsaturated fatty acids were identified as potential flavor precursors. • More aldehydes, some ketones, esters and less hydrocarbons contribute to aroma. • 13 key volatile compounds were identified as affecting the overall odour. • Lipid oxidation, degradation and Maillard reaction are the main reaction for soup. Deodorization and umami enhancement are important challenges in promoting and consuming fish products. The aim of this study was to establish whether exogenous addition of oxidized lipids and cysteine can improve the fishy, umami and create a characteristic flavor in tilapia fish head soup. The results revealed that adding oxidized lipids and cysteine enhanced the sensory attributes of fish head soup and promoted the production of pleasant-tasting amino acids and fewer bitter amino acids in the Maillard reaction. Additionally, the combination increased the levels of well-flavored aldehydes, esters, heterocyclic compounds and less hydrocarbons in the fish head soup. Among the 13 volatile compounds screened, nine were identified as characteristic aromas of fish head soup, including nonanal, (E,E)-2,4-decadienal, 1-octen-3-ol, (E)-2-decenal, acetic acid, hexanal, heptanal, 2-octenal, and decanal. Exogenous lipid oxidation products, fatty acid oxidation, and Maillard reaction can improve the aroma and umami of tilapia fish head soup. [ABSTRACT FROM AUTHOR]