Influence of protein isolates from Pangas processing waste on physico-chemical, textural, rheological and sensory quality characteristics of fish sausages

Protein isolates from Pangas waste were incorporated into sausages at different concentrations (0.0, 5.0, 10.0, 25.0 and 50.0 g/100 g) followed by extensive investigation of its physico-chemical, textural, sensory and rheological properties. Increasing protein isolate content in sausages increased its protein content (11.57-15.79 g/100 g) but decreased the fat content (10.70-5.25 g/100 g) and lightness (p < 0.05). Addition of isolates at 10 g/100 g level significantly improved the cooking yield and reduced the expressible fluid of emulsion (p < 0.05). Increasing protein isolate content in sausages decreased the gel strength as well as folding test scores (p < 0.05). Among all the samples, sausages without isolates had highest gel strength and folding score (2648.67 g cm and 5.0). Adding isolates at 10, 25 and 5 g100 g(-1) level decreased the folding score to 4.0 and gel strength to 2176.60, 2012.55 and 2007.53 g cm, respectively. Addition of Pangas isolates to sausages did not cause significant differences in its sensory characteristics and the overall acceptability scores ranged from 7.8 to 8.2. Among various levels tested, Pangas protein isolates at 10 g/100 g level was found to produce sausages with better functionality.