Preparation, characterization of food grade phycobiliproteins from Porphyra haitanensis and the application in liposome-meat system

•PBPs showed nutritional value for the highly essential amino acids content of 43%.•The hydrophobic amino acids related to antioxidant activity took up 50.47%.•PBPs exhibited lipid peroxidation inhibition activities both in linoleic acid and liposome-meat system.•The functional properties of PBPs suggest their potential application in food system.

Phycobiliproteins (PBPs), the family of hydrophilic pigment proteins with fluorescence, have great potential in food industry as functional ingredients. The objective of this research was to prepare and characterize food grade phycobiliproteins from Porphyra haitanensis, and to investigate its application in liposome-meat system.The existence of both phycoerythrin and phycocyanin in food grade PBPs was confirmed using UV-visible spectrum, with 3 absorbance peaks at wavelength of 498 nm, 560 nm and 615 nm, respectively. The purity ratio of food grade PBPs was 1.39, which was enhanced to 3.14 by DEAE chromatography. The optimum pH for emulsifying and gelation properties was 10, and the optimum temperature for emulsifying property was 40 °C. The IC50 values of food grade PBPs and purified PBPs were as follows: DPPH radical scavenging activities were 166 μg/mL and 84 μg/mL, ABTS radical scavenging activities were 29 μg/mL and 32 μg/mL, Fe2+ chelating activities were 200 μg/mL and 32 μg/mL, respectively. Moreover, both linoleic acid peroxidation and the growth of TBARS value in liposome-meat system could be inhibited significantly by phycobiliproteins. The findings indicated that food grade PBPs from Porphyra haitanensis are applicable as a potential additive to be utilized in liposome-meat system.