Effect of processing conditions on the oxidation of cholesterol in ghee

Authors

  • Naresh Kumar,

    1. Division of Dairy Chemistry, National Dairy Research Institute, Karnal 132 001, India
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  • O P Singhal

    Corresponding author
    1. Division of Dairy Chemistry, National Dairy Research Institute, Karnal 132 001, India
    • Division of Dairy Chemistry, National Dairy Research Institute, Karnal 132 001, India
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  • Paper presented at the International Symposium on Biological Oxidation Systems. October 1989. Bangalore, India.

Abstract

The cholesterol oxidation products (COP) in fat-rich dairy products were identified and quantified. Fresh cream contained no COP whereas fresh butter contained trace levels of 7β-hydroxy- and 5,6α-epoxycholesterol. Low levels of various major COP were present in ghee (clarified butter fat). Intermittent heating and frying of ghee induced severe oxidation of cholesterol and a number of COP were detected by GC and TLC. Most atherogenic COP. viz 25-hydroxycholesterol and cholestantriol, were formed more in intermittently heated ghee (8.1-9.2% of the total COP) than in fried ghee samples (7.1 %).

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