Organoleptic and chemical assessment of two frozen marine fishes obtained from markets in four agricultural zones of Oyo State, Nigeria
Sensory and non-sensory assessment of frozen fish: Sardinella species and Micromesistius poutassou obtained from four Agricultural Development Programme (ADP) zones (Ibadan/Ibarapa, Ogbomoso, Oyo and Saki) of Oyo State were carried out. Overall acceptability was based on 7-point Hedonic scale (very much liked (7) - very much disliked (1). Chemical tests [Hypoxanthine (Hx), Peroxide value (PV), Trimethylamine (TMA) and Free fatty acid (FFA)] were carried out using standard methods. Data were analyzed using the mean, standard deviation and t- test.Overall acceptability of the two frozen fish species was between 5.47±0.20 and 5.90±0.08.Hx values varied between 22.15±1.04 and 25.96±0.53mg/100g fish for Sardinella spp. and M. poutassou respectively. The values recorded for both Sardinella spp. and M. poutassou were between 17.48±0.81 and 19.79±1.03 meq/kg for PV; 19.03±065 and 23.63±0.60 mg/100g fish for TMA and between 1.38±0.07% and 1.85±0.31% for FFA respectively. In both Sardinella spp. and M. Poutassou respectively, Oyo Zone had the least PV (17.48±0.81; 17.90±0.60meq/kg), TMA level (20.58±0.90; 19.03±0.65mg/100g). Sardinella spp. samples from the Ogbomoso Zone had highest PV (18.83±0.60meq/kg), FFA (1.85±0.13%) and TMA (23.63±0.60mg/100g) levels, and also the highest FFA values (1.81±0.19%) in M. poutassou. Hypoxanthine and TMA valueswere significantly different in the Sardinella spp. and M. poutassou samples across the zones, respectively.Quality of frozen fish was best in the Oyo Zone. All sensory and non-sensory indicators of fish quality were however within acceptable limits in the four zones of Oyo State.
Keywords: Frozen fish, Sensory assessment, Chemical assessment, ADP zones, Oyo state