Functional characteristics of protein isolates from chicken liver

The study was conducted to isolate protein from chicken liver and characterization of its techno-functional properties. Prior to protein isolation, protein solubility test was carried out to know the highest solubility at a particular pH. The isolates obtained were freeze dried and subjected for different quality evaluation and comparison was made with the chicken liver powder. Higher protein solubility was observed at pH 1.5, 2.0 11.0 and 11.5 with significantly higher yield at alkaline pH and highest total protein content at pH 11.0. The bulk density of protein isolates was significantly lower than that of whole chicken liver powder. As compared to whole liver powder, the whiteness values were significantly higher for isolates and highest value was observed for isolate at pH 11.5 and accordingly had lowest total pigment content. The other techno-functional quality parameters such as fat absorption capacity, water absorption capacity, foaming capacity, foaming stability, emulsifying activity index, emulsifying stability index improved in all types of isolates. The ABTS and DPPH assays were also reflected significantly higher antioxidant activity in protein isolates as compared to whole liver powder. The protein isolates form poultry liver can be utilized for production of high-quality protein isolates.