Oxidative stability of walnut oils extracted with supercritical carbon dioxide



Supercritical carbon dioxide (SC-CO2) was used to partially defat walnuts, and the oxidative stability of the extracted walnut oils was assessed. The SC-CO2-extracted oils were less stable during accelerated storage in the dark than was pressed walnut oil, as determined by PV, headspace analysis by solid-phase microextraction, and sensory methods. The SC-CO2-extracted oils, however, exhibited greater photo-oxidative stability than did pressed walnut oil by all of these methods, possibly because of the presence of chlorophyll in the pressed oil. Oxidative stability indices and tocopherol contents were significantly lower in the SC-CO2-extracted oils than in pressed oil.

Key Words

Oil oxidation oxidative stability supercritical carbon dioxide extraction walnut oil 


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© AOCS Press 2003

Authors and Affiliations

  1. 1.Food Science and Human Nutrition DepartmentIowa State University 2312 Food Sciences BuildingAmes
  2. 2.Center for Crops Utilization ResearchIowa State UniversityAmes
  3. 3.Campbell FoodsCamden

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