Quantification of Alaska pollock surimi in prepared crabstick by competitive ELISA using a myosin light chain 1 specific peptide

A competitive enzyme-linked immunosorbent assay (ELISA) was developed for quantification of Alaska pollock (AP) surimi in crabsticks. Identification of fish species is complicated by processing, cooking, and additional ingredients. ELISA is a powerful tool for identification and quantification of fish species. Polyclonal antibodies were raised in rabbits against a 15-amino-acid peptide (Ala–Pro–Lys–Lys–Asp–Val–Lys–Ala–Pro–Ala–Ala–Ala–Ala–Lys–Lys) determined from the myosin light chain 1 (MLC 1) of AP. Immunoblotting showed the anti-pep-AP antibody had no significant cross-reactivity with protein additives. However, cross-reactivity of the MLC 1 from Pacific whiting, and threadfin bream surimi was observed. MLC 1 was purified from AP surimi and used as the coating protein in the competitive ELISA. MLC 1 was serially diluted and had a R2 of 0.9845 following a logarithmic curve. All estimations of AP surimi were within 9% of the actual value. Inter-assay coefficients of variance ranged from 4.2% to 4.9%.