The effect of the cooking method on rainbow trout (Oncorhynchus mykiss) fillets

Anotace: Fish is nutritious seafood and contains protein with high biological value and essential nutrients for the human body. In Iran, the fish Oncorhynchus mykiss is locally known as Ghezelala and is a commercial fish species. Different methods were used to process the fish: boiling, frying in sunflower oil and grilling. This research investigated on effect of various cooking methods on proximate pH and cooking loss of fresh fish (Oncorhynchus mykiss). The highest and lowest values for protein were found in fish processed using grilling (18.51%) and frying (16.52%), respectively (p <0.05) compared to the fresh sample (18.20%). The fat content of the fried sample showed significantly highest (5.16%) (p <0.05), while the lowest fat content was found for the boiled sample (20.57%) compared to the fresh fat (24.36%) (p <0.05). Comparing the loss percentage of samples in different cooking methods showed that the boiled sample had the lowest value (25.46%) and the fried sample with the highest value (45.02%) (p <0.05). pH value in the boiled sample was the highest (6.74%), while the grilled sample had the lowest (6.63) compared to the fresh sample (6.54). The highest energy value was found for the fried sample (578.48 kcal/100g), and the lowest was for the boiled sample (269.29 kcal/100g). The results suggest that the boiled and grilled fish found higher nutritional quality due to the relatively high protein content, the most needed nutrients. The results also showed that all cooking methods did not significantly affect in mineral content of the fresh fish.