Evaluation of chemical and physical Characteristics of flesh, mince and burger of Clarias sp.(Garmout) treated by dilute saline.

Abstract

The aim of present study is assess the quality of fish flesh, mince and burger made from Clarias sp. meat. Also this research was conducted to study the effect of washing by dilute saline on chemical and physical characteristics of mince and burger in addition to sensory attributes for burgers. The fish were purchased from ELmourda fish market in the period of August to October (2011). Six and half kilograms of Clarias sp. were filleted. First fillet divided into two. Fresh fillets were analyzed for quality and the other was frozen for 24 hours before preparation. Then two frozen fillets divided into groups. The first group washed with dilute saline (0.2%) and left in saline for 20 minutes. The second group was kept unwashed. Both fillets were passed through a meat grinder to obtain homogenous mixture, and after that some ingredients were added. Then the mixture was divided into mince and burger and analyzed for quality. The result obtained reveal that the percentage of fillets in Clarias sp. was 46.15%. The proximate analysis of fresh fillets were 80.45% for moisture, 19.55% for dry matter, 11.09% for crude protein, 2.15% for fat and 6.33% for ash. The mean values of macro minerals for fresh fillets were 545 mg /100 g for VIII calcium, 299.6 mg /100 g for magnesium, 45.27 mg /100 g for sodium, 131.27 mg /100 g for potassium, and 100 mg/100 g for phosphorus, and physical characteristics for fillets were 6.91 for pH, 4.66 for WHC and colors values were 36.1 for lightness (L), 17.5 for redness (a) and 10.1 for yellowness (b). The result obtained from this study revealed that there were significant increase (P > 0.05) in moisture and fat content of mince washed fillets, protein value decreased significantly (P > 0.05) in mince of washed fillets. But ash value was not significantly different (P < 0.05), also the macro minerals values were not significantly different (P < 0.05) between both groups of mince, except sodium value, which was significant increase (P > 0.05) in mince of washed fillets. The present study also revealed a significant difference (P > 0.05) in pH value, while water holding capacity (WHC) was not significantly different (P < 0.05) between mince groups. Decrease in color values were high significant in lightness (L) value and redness (a) value in mince of washed fillets, where, yellowness (b) value was increased significantly in mince of washed fillets. Moisture and fat contents from fish burger prepared from washed fillets were increased significantly (P > 0.05), while there was a significant decreased (P > 0.05) in protein value. On the other hand, there was no significant different (P < 0.05) in ash value between burger groups. Calcium and magnesium values increased significantly (P > 0.05) in fish burger prepared from washed fillets, while phosphorus decreased significantly (P > 0.05) and there was no significant difference (P < 0.05) in sodium and potassium values between both groups of fish burger. There were significant differences (P > 0.05) in physical characteristics of fish burger. The pH value and WHC increased significantly (P > 0.05) in fish burger prepared from washed fillets, while there was a significant decreased (P > 0.05) in lightness (L) and yellowness (b) value in fish IX burger from washed fillets. On the other hand there was no significant difference (P < 0.05) in redness (a) value between fish burger groups. Sensory parameters (taste, color, juiciness and texture) of two the groups of fish burger were not significantly different (P < 0.05). While flavor attribute was significantly different between two groups of burger. Flavor value was lower (slightly intense) in fish burger prepared from mince of washed fillets compared to the burger made from unwashed fillets.