ENZYMATIC PRETREATMENT OF JOJOBA SEEDS TO FACILITATE OIL EXTRACTION

A short enzymatic pretreatment of crushed jojoba seeds enabled centrif ugal extraction of more than 25% of the oil contained within the seed matrix. Commercially available hydrolytic enzymes, including glucanase s and proteases, were selected on the basis of their capability to rel ease soluble sugars and proteins and then examined for their effect on release of the oil from the seed particles. Pectinases and xylanases led to a release of 5-15% of the total sugars within the seeds, and en abled extraction of 10-15% of the oil. Treatment with proteases releas ed 10-15% of the protein contained in the seeds, but was significantly more effective in releasing 25% of free oil. Only proteases activity caused the entrapment of about 60% of the oil in the form of extremely stable emulsion. Several denaturing treatments of the seed matrix wer e performed to prevent the formation or destabilize the emulsion phase . Autoclaving the seeds to denature proteins in their matrix yielded m ore than 50% release of the oil. Similar treatment of the dense emulsi on to denature its proteins released more than 25% of the oil from the emulsion phase. Denaturation and precipitation of seed proteins by 10 % w/v of trichloroacetic acid released more than 55% of the oil. The r esults indicate that amphipathic (hydrophobic-hydrophilic and surface active) proteins are responsible for the formation and stabilization o f the dense emulsion phase which counteracts efficient extraction of t he oil.