Thiol concentration, structural characteristics and gelling properties of bovine heart protein concentrates

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>Consumer demand for proteins from animal sources has been increasing with economic growth of the populations. Freeze-dried ground bovine heart was treated using supercritical-CO<SUB>2</SUB> (SC–CO<SUB>2</SUB>) at different pressures (20, 30 and 40 MPa) and hexane to produce a protein concentrate. Thiol concentration, structural and gelling properties of the control bovine heart and bovine heart protein concentrates (BHPCs) were investigated. SC-CO<SUB>2</SUB> treatment at 20 MPa led to an increased (<I>p</I> < 0.05) thiol (–SH) content (74.08 nmol/mg protein) than those for the control and other BHPCs. Fourier–transform infrared (FT–IR) spectroscopy showed increased secondary structure of α–helix and parallel β–sheet content for SC-CO<SUB>2</SUB>–treated bovine heart protein when compared to the control and hexane–treated bovine heart protein. Integrated light scattering in protein suspension showed SC-CO<SUB>2</SUB>–treated samples had higher cumulative values (Q3) and density (q3) for the particle size distribution. SC-CO<SUB>2</SUB>–treated BHPC had better physicochemical properties without structural deterioration of proteins resulting in increased functional properties such as solubility (31.08 g/100 g bovine heart), viscosity and gelling capacity (least gelation concentration 10 g/100 mL water). Bovine heart proteins may serve as a good source of quality proteins for different food applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bovine heart was treated using SC-CO<SUB>2</SUB> and hexane to produce a protein concentrate. </LI> <LI> SC-CO<SUB>2</SUB>–treated sample had higher thiol (-SH) content than the control and other samples. </LI> <LI> FT-IR spectra showed SC-CO<SUB>2</SUB>–treated samples had higher α–helix and β–sheets. </LI> <LI> Integrated light scattering showed greater particles in solution for SC-CO<SUB>2</SUB>–treated sample. </LI> <LI> SC-CO<SUB>2</SUB> treatment resulted in increased functional properties of the protein concentrates. </LI> </UL> </P>