Physico‐chemical and functional properties of proteins from spray dried algae (Spirulina platensis)

The nitrogen solubility index of proteins from Spirulina platensis as a function of pH in the range of 1 to 12 has been determined both in water and different concentrations of sodium chloride using the spray dried samples. Solubility characteristics show maximum solubility in the pH range of 8 to 10 in water and pH 6.0 ± 0.5 in 0.5 M sodium chloride. The ultraviolet and visible spectra have maxima at 285 and 620 nm, respectively. Fluorescence emission spectrum shows a maximum emission at 340 nm arising from tryptophanyl groups. The sedimentation velocity experiment shows two major fractions with sedimentation coefficient of 2.8 and 4.9 S. The functional properties of the protein are determined using the spray‐dried sample. The result for water absorption (292 g/100 g), fat absorption (56 g/100 g), foaming and emulsion properties were determined and compared with egg protein as standard. An attempt is made to correlate the changes occurring as a result of spray drying of the functional properties to the physico‐chemical properties of the protein in solution.