FILLET QUALITY DIFFERENCE OF MICROPTERUS SALMOIDES CULTURED UNDER DIFFERENT MODES

<italic>Micropterus salmoides</italic> is a commercially important freshwater aquaculture species in China, facing growing demand amid declining wild resources, necessitating improvements in farming efficiency and product quality. The study focused on evaluating the differences in muscle quality of <italic>M. salmoides</italic> reared in four different aquaculture systems in Chongqing: reservoir cage culture (R), pond culture (P), raceway culture (C), and high-place pond culture (H). This evaluation was conducted by examining growth indices, apparent traits, meat quality, aroma, and nutritional value. Results showed that there were no significant differences in specific growth rate (SGR) among groups (<italic>P</italic>&gt;0.05), but the weight gain rate and feed conversion ratio of group R showed slight advantages. Additionally, significant quality differences were observed across the four culture systems in terms of the condition factor, viscerosomatic index, and hepatosomatic index of the fish in the C group were significantly lower than those in the other three groups (<italic>P</italic>&lt;0.05). Moisture content, crude fat, and crude protein contents varied notably across systems (<italic>P</italic>&lt;0.05), with the R group exhibiting the highest crude protein and the lowest crude fat content. A total of 16 amino acids were detected in all groups, with the R group showing significantly higher non-essential amino acids (NEAA) and delicious amino acids (DAA) contents compared to the other groups (<italic>P</italic>&lt;0.05), along with the highest ratio of ∑DAA/TAA (total delicious amino acids to total amino acids). Additionally, the ratios of ∑EAA/TAA (total essential amino acids to total amino acids) and ∑EAA/NEAA in the four groups exceeded the ideal pattern standards recommended by the Food and Agriculture Organization of the United Nations (FAO)/World Health Organization (WHO). A total of 16 fatty acids were identified, with the R group showing the highest ∑PUFA (total polyunsaturated fatty acids) content, in which the n-6 fatty acids comprised 34.57% of total fatty acids. A total of 52 flavor compounds were detected in the muscle of <italic>M. salmoides</italic>, with the R group containing a higher content and greater variety of pleasant odor substances. Histological analysis revealed that the R group muscle fibers had smaller diameters and denser arrangements compared to other groups. The results demonstrated that reservoir cage culture (R) not only enhanced the growth of <italic>Micropterus salmoides</italic> and improved the feed conversion ratio (FCR), but also significantly exhibited superior muscle texture, more balanced amino acid nutrition, higher unsaturated fatty acids diversity, and richer volatile flavor profiles, significantly enhancing muscle quality. These findings highlight reservoir cage culture as a preferable aquaculture system for <italic>M. salmoides</italic>.