• EXTRACTION, CHARACTERIZATION AND FUNCTIONAL PROPERTIES OF JOJOBA PROTEINS

      Price, Ralph L.; Cardoso, Fernando Antonio (The University of Arizona., 1980)
      Two defatted jojoba seed meals were prepared; one using whole seeds (JM), and the other from which seed coats were removed prior to extraction of the oil (DJM). The protein content of both meals was about 24%. The proteins from JM and DJM were extracted according to their solubility in water, dilute saline, alcohol, and alkali solutions. These extractions produced the albumin, globulin, prolamine and glutelin protein concentrates. The major concentration of proteins in jojoba were the albumin (65%) and globulin (21%) fractions. The amino acid compositions of both JM and DJM were found to be very similar. Methionine was the limiting amino acid in jojoba seed proteins. The protein composition was determined, and the molecular weight was estimated through chromatographic analysis using gel filtration on Sephadex G-100 and ion-exchange chromatography on DEAE-Sephadex and CM-Sephadex. At least 5 separate protein fractions in each of the albumin and globulin concentrates and 8 separate protein fractions in each of the prolamine and glutelin concentrates were found. The molecular weights of jojoba protein concentrates varied from 19,000 to 150,000 for albumins, from 18,000 to 128,800 for globulins, from 11,700 to 141,200 for prolamines, and from 29,500 to 150,000 for glutelins. All protein concentrates showed very good fat absorption and solubility at values of pH below 3.0 and above 4.0. Albumins and globulins showed very good foamability and emulsion properties. The prolamine and glutelin concentrates showed very poor foamability and emulsion properties. The buffering capacity of jojoba protein concentrates was very low.