Effects of Spartina alterniflora Extract on Growth Performance and Flavor Quality in Mud Crab (Scylla paramamosain)

The steady rise in living standards has created a growing market demand for aquatic products with superior flavor profiles and enhanced nutritional value. To address this need, the present study investigates the effects of dietary supplementation with Spartina alterniflora (SA) extract on growth performance and muscle quality parameters in mud crabs (<i>Scylla paramamosain</i>). In a 63-day feeding trial, 150 juvenile crabs received experimental diets containing 0% (control), 0.05%, 0.1%, 0.15%, or 0.2% SA extract. The results showed that optimal growth enhancement was achieved with 0.15% supplementation. Flavor analysis revealed dose-dependent improvements in umami characteristics. Supplementation at ≥0.1% significantly increased the concentrations of key umami compounds; their taste activity values; and equivalent umami concentrations. Fatty acid analysis showed that extract supplementation modulated lipid composition, increasing eicosapentaenoic acid while decreasing docosahexaenoic acid content, with the n-3/n-6 ratio remaining stable across all treatments, except in the 0.2% group. Volatile compound analysis demonstrated that ≥0.1% supplementation enhanced aldehyde production, improving flavor profiles. Interestingly, while 0.1-0.15% supplementation produced predictable flavor modifications, the 0.2% group showed atypical responses in flavor profiles. Supplementation with 0.15% SA extract optimally enhanced both growth performance and muscle quality while maintaining nutritional value, supporting the potential utility of this invasive species as a sustainable aquafeed additive. This study provides novel foundations for the regulation of flavor quality in aquatic food animals.