Quality Evaluation and Nutrient Profiling of Siganus fuscessens from Multiple Regions in Guangxi, China

This study assessed muscle quality and nutritional components of farmed Siganus fuscescens (rabbitfish) from Hepu, Qinnan and Tieshangang in Guangxi, China. Proximate nutrients, amino acids and fatty acids in fish muscle were determined. Qinnan samples had higher moisture and crude protein but lower ash content. Glutamic and aspartic acids dominated detected amino acids. The ratios of essential amino acids to total amino acids (EAA/TAA) and to non-essential amino acids (EAA/NEAA) ranged from 35.63 to 36.16% and 68.47 to 69.33%, respectively. Qinnan fish possessed the highest contents of total amino acids (TAA), essential amino acids (EAA), flavor amino acids (FAA), and the highest essential amino acid index (EAAI), indicating superior protein quality. The fatty acid profiles revealed that saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) each constituted more than 20% of the total fatty acids. Moreover, fish from Tieshangang were particularly rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Obvious regional nutritional differences existed in cultured rabbitfish. This work provides references for its quality assessment, resource utilization and targeted feed development.