Abstract
The effect of acid and alkaline pH shift processes on removal of total lipids, cholesterol, nucleic acids and haem pigments during production of protein isolates from broiler meat was investigated. The gel-forming ability of resulting protein isolates were evaluated in comparison with raw broiler meat and water washed broiler meat. Significant reduction of total lipids, cholesterol, nucleic acids and haem proteins was obtained from both pH shift processes (p < 0.05). Acid process recovered more protein with less total haem pigments resulting in a greater breaking force and whiteness of the isolate gel compared to alkaline counterpart (p < 0.05). However, protein isolate gels showed inferior deformation and water holding capacity to washed mince gel (p < 0.05). Therefore, the pH shift processing could be used to produce a functional protein isolate with low nucleic acids, haem pigments and lipids and, thereby, reduced cholesterol level. The protein isolates, particularly acid version, still had good gelling properties.
Quality of Protein Isolates and Hydrolysates from Baltic Herring (Clupea harengus membras) and Roach (Rutilus rutilus) Produced by pH-Shift Processes and Enzymatic Hydrolysis