TOCOL AND PHYTOSTEROL COMPOSITION OF EDIBLE OILS IN
THE EGYPTIAN MARKET
MOHAMED FAWZY RAMADAN HASSANIEN
1
Department of Agricultural Biochemistry, Faculty of Agriculture, Zagazig University, Zagazig 44519, Egypt
1
Corresponding author. TEL: +2-055-2320282
or +2-012-9782424; FAX: +2-055-2287567 or
+2-055-2345452; EMAIL:
mframadan@zu.edu.eg
Received for Publication November 19, 2010
Accepted for Publication September 18, 2011
doi:10.1111/j.1745-4549.2011.00621.x
ABSTRACT
The goal of this investigation was to quantify phytosterols (ST) (campesterol,
b-sitosterol, stigmasterol, b-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 mg/g) samples
while palm oil samples had the lowest ST level (660 mg/g). Values of total ST
were 2,872 and 3,443 mg/g for sunflower and blended oil samples, respectively.
b-sitosterol was the main ST (ca. 70%), followed by campesterol (ca. 16%) and stig-
masterol (ca. 9.4%), while b-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 mg/g, respectively. In sunflower and
blended oil samples, a-tocopherol was the main TO which accounted for more than
80% of total TO, while a-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 compa-
nies. 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.
INTRODUCTION
Edible vegetable oils are a major source of phytosterols (ST)
and tocols (TO) in the diet. They contribute 20 and 41% of
the total a-tocopherol equivalent intake in the U.S.A. and in
Finland, respectively (Murphy et al. 1990; Heinonen and
Piironen 1991), and to 26, 39 and 50% of the total ST intake in
Holland, Finland and Spain, respectively (Normén et al. 2001;
Valsta et al. 2004; Jiménez-Escrig et al. 2006).
Plant sterols are isoprenoid compounds with a sterol
nucleus and an alkyl chain. Most plant sterols have a double
bond in position C-5 in the nucleus, while others are totally
saturated and called stanols (Schwartz et al. 2008). In this
work, the term “phytosterols, ST” is used for both sterols and
stanols. Together with cholesterol, ST are chemically classified
as 4-desmethyl-sterols, wherein more than 250 types of
ST have been reported (Piironen et al. 2000a,b). The most
common ST are sitosterol (24a-ethylcholest-5en-3b-ol),
Journal of Food Processing and Preservation ISSN 1745-4549
531 Journal of Food Processing and Preservation 36 (2012) 531–538 © 2012 Wiley Periodicals, Inc.