Karakteristik Morfologi, Fisik, Kimia, dan Profil Asam Amino Ikan Rucah sebagai Bahan Baku Surimi

Abstract

Trash fish such as juwi (Anodontostoma chacunda), peperek (Photopectoralis bindus), and tembang (Sardinella fimbriata) are low-value bycatch species commonly found in the waters of Tuban and Lamongan. These three species have high potential as raw materials for surimi production. This study aimed to compare the morphological, physical (color and texture), chemical (proximate composition), muscle microstructure (SEM), and amino acid profiles of these three fish species, as well as to determine the most suitable species for surimi production. A two-factor Randomized Complete Block Design (RCBD) was applied, with fish species (A) and sampling locations in Tuban and Lamongan (B) as the experimental factors. The results showed that S. fimbriata had the largest body dimensions, highest redness (a* = 6.8–7.1) and yellowness (b* = 8.9–9.3) values, highest protein content (24.24–36.23%), lowest moisture (61.89–73.50%), and firmest texture (176.2–202.2 gf). SEM observations confirmed that the muscle fibers of the S. fimbriata have the densest and most homogeneous structure. In contrast, P. bindus exhibited the brightest flesh color (L* = 51.9–58.6) as well as the highest total essential (13.53%) and non-essential (19.99%) amino acid content, but had the loosest microstructure. However, amino acid content reflects nutritional quality, not structural density. Based on the overall De Garmo effectiveness test, S. fimbriata was identified as the low-value fish species with the greatest potential for surimi production based on the surimi quality requirements in SNI, as it has superior protein content, the lowest moisture content, the firmest texture, and the densest muscle microstructure