Physico-Chemical and Functional Properties of Extracted Capia Pepperseed (Capsicum annuum L.) Proteins

Capia pepperseed meals obtained from cold pressing by applying pretreatments such as roasting and enzyme treatment were used for protein extraction. The optimum extraction conditions were pH 9.0 and 0.2 or 0.6 M NaCI solution with pH 4.0 and 4.5 for isoelectric point precipitation. Under these conditions, the protein yields were 40, 33 and 15 % for control, roasted and enzyme treated samples, respectively. The functional properties like water and oil holding capacities (WHC and OHC), emulsifying activity (EA) and emulsion stability (ES) values, foaming capacity (FC) and foam stability (FS) values indicated that these proteins can be utilized in food products. Furthermore, the thermal properties and amino acid composition of the samples were measured. Gel electrophoresis showed 5 bands, and some were absent in the enzyme treated samples, indicating some protein loss by the enzyme treatment. In conclusion, capia pepperseed proteins are nutritionally balanced, and a limited pre-roasting would be beneficial for enhanced functional properties. Hence, protein extracts from the cold pressed pepperseed meals could be used for human food product applications