Phytosterol recovery from oilseeds: Recent advances

Phytosterols are high value compounds having hypocholesterolemic and antioxidant properties, predominantly present in seed oils. High temperature during pretreatment of oilseeds and high initial moisture content (>10%) results in the degradation of phytosterols and have considerable effect on its yield during extraction. As more than 40% of sterols are lost during oil refining processes, the by-products of refining industries can be excellent sources of this value-added product. This review focuses on the scope of various strategies to maximize the yield of phytosterols from oilseeds. Storage as well as pretreatment of oilseeds are as important as the method of extraction to prevent degradation of sterols. Solvent crystallization, counter current chromatography, supercritical fluid extraction, and enzymatic transesterification are some of the current techniques employed for phytosterol recovery. Practical applicationsPhytosterols are high value compounds present in seed oils having cholesterol-lowering properties. Its extraction and isolation from oilseeds for the purpose of fortification of food stuffs would be the best way to harness its virtues. But since they are present in very low quantity in oils (0.5 to 2 %), its recovery becomes quite difficult. Phytosterols are also lost during seed storage, pretreatment and oil refining processes. Hence it is necessary to take appropriate measures to retain these valuable compounds in oil. This review focuses on the scope of various strategies to maximize its yield during extraction by different methods.