The Free and Ester Sterol Content of Various Foodstuffs

Abstract
The free and ester cholesterol content of various foodstuffs has been determined. In general most of the cholesterol in meat is in the ester form (50 to 70%); in fish and sea food most of the cholesterol is present in the free form (55 to 95%). Butter and cream have equal quantities of free and ester cholesterol, whereas less than 20% of the cholesterol present in eggs and cheeses is in the esterified form. The ferric chloride modification of the Liebermann-Burchard reagent used for cholesterol analysis was found to be equally useful for determination of β-sitosterol. Using this reagent the free and ester sterol content of various edible oils was determined. In two samples of margarine there were equivalent amounts of free and ester sterol. In the other fats analyzed, most of the sterol was present in the free form (80 to 100%).