Jojoba, Simmondsia chinesis, a shrub native to the Sonoran Desert, has seeds with a high percentage of oil. The oil, which has properties similar to sperm whale oil, is expressed with heat and pressure, leaving behind a pressed meal rich in protein and carbohydrate. High concentration of a cyanoglycoside, simmondsin, and polyphenolic compounds in the meal make it unusable for animal or human consumption. Commercial means of protein extraction were improved by washing the protein concentrate with methanol, acetone, and acidic methanol to remove sugars, polyphenolic components and simmondsin. A concentrate with 85% protein, less than 0.3% polyphenolic compounds, and less than 1% simmondsin resulted. The foamability, water absorption, oil absorption, gelation, emulsification and nitrogen solubility were comparable to other plant protein concentrates. Fewer than 15 proteins in the pressed meal and concentrates were detected using PAGE (12.5% T, 2.4% C) in a Laemmli discontinuous system. The proteins were deficient in the sulfur amino acids, and marginal in threonine and lysine. The amino acid imbalance might be partially responsible for poor weight gain and other toxicity symptoms reported previously.

Jojoba albumins and globulins were treated with jojoba tannins to study the protein-tannin complex formation. Trypsin and chymotrypsin were also treated with jojoba tannins to determine the change of enzymatic activity. The treated albumins and globulins were fractionated by gel filtration before and after treatment. Two albumin fractions did not appear after treatment, but a new fraction appeared with a shorter elution time. A precipitate was formed by addition of jojoba tannins to the jojoba globulins, and two globulin fractions did not appear after treatment. Trypsin was completely inhibited by 5.80 μg of tannin/ml. Chymotrypsin was completely inhibited by 36.44 μg of tannin/ml. Seven two-hour successive extractions with methanol were sufficient to obtain a jojoba meal which, when mixed at 15% in a ration with soybean, resulted in excellent growth of mice. Detannification of jojoba meal with methanol and acid methanol extracted other toxicants, because mice fed 15% of this jojoba meal gained more weight than the control. Acid methanol extraction was more effective than methanol or aqueous extraction in removing tannins; water extracted more protein and less tannin.