TOCOL AND PHYTOSTEROL COMPOSITION OF EDIBLE OILS IN THE EGYPTIAN MARKET

Abstract

ABSTRACT The goal of this investigation was to quantify phytosterols (ST) (campesterol, β-sitosterol, stigmasterol, β-sitostanol and campestanol) and tocols (TO, tocopherol and tocotrienol) in the edible oils (corn oil, sunflower oil, blended oil and palm oil) in the Egyptian market. The best source of ST was corn oil (4,814 µg/g) samples while palm oil samples had the lowest ST level (660 µg/g). Values of total ST were 2,872 and 3,443 µg/g for sunflower and blended oil samples, respectively. β-sitosterol was the main ST (ca. 70%), followed by campesterol (ca. 16%) and stigmasterol (ca. 9.4%), while β-sitostanol and campestanol were detected in some oils in small amounts or traces. Levels of total TO in corn, sunflower, blended and palm oil samples were 891.4, 716.1, 707.5 and 311.8 µg/g, respectively. In sunflower and blended oil samples, α-tocopherol was the main TO which accounted for more than 80% of total TO, while α-tocopherol was found in lower levels in corn and palm oils accounting for ca. 40% of TO. PRACTICAL APPLICATIONS Vegetable oil production in Egypt is centralized with few manufacturing companies. Epidemiological studies on ST and TO consumption and health impact are difficult to find, however, because few databases are found. The aim of the present study was to survey for the first time the ST and TO composition of a variety of the main commercially available edible oils in the Egyptian market. The TO and ST levels of oil samples were determined using validated normal phase high-performance liquid chromatography and gas liquid chromatography with flame ionization detection methods. There is a wide spread of concentrations of ST and TO in the edible oils consumed in Egypt. As this survey database is meant to be used in other prospective cohort studies, a slight overestimation of ST and TO levels may be less important because the database only needs to rank the ST and TO intake of people in order to study associations with morbidity and mortality. The database levels presented in this work are valid for ranking of ST and TO intake in epidemiological studies.