Processing of vegetable oils using polymeric composite membranes.

A study was conducted to process crude soybean and rapeseed oils using
polymeric composite membranes without the addition of organic solvents. The
membranes selectively rejected phospholipids, color pigments and certain
oxidation products while permeating tocopherols. The color reduction in
soybean oil permeate ranged from 74 to 8070. The reduction of oxidation
products varied between 50 and 87%. The UV spectra suggested that certain
undesirable oxidation changes occum’ng during the conventional process were
eliminated. The increase in the tocopherol content in the permeate ranged
between 12 and 15%. The long-term experiments (97days) indicated good
membrane stability. Howevel; the membrane process does not seem to separate
free fatty acids from triglycerides and the permeate flux also needs to be
improved