3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
P22 PhyTOSTEROL AND FATTy ACID PROFILE
OF FOuR EDIbLE OILS PROCESSED IN
ROMANIA
FRAnCISC VASILE DULF a , CARMEn SOCAIU a ,
COnSTAnTIn BELE a , ADELA PInTEA a and MIHAELA
UnGURESAn b
a University of Agricultural Sciences and Veterinary Medicine,
3–5 Mãnãstur Str., 400372, Cluj-Napoca, Romania,
b Technical University of Cluj-Napoca, Chemical Department,
103–105 Muncii Bvd., 400641, Cluj-Napoca, Romania,
francisc_dulf@yahoo.com
Introduction
Triglycerides represent the principal component (95–
98 %) of most edible oils obtained from seeds and fruits.
Small amounts of sterols, free fatty acids, hydrocarbons,
tocopherols, phospholipids and triterpenic acids are also present.
Fatty acids occur predominantly as esters of glycerol,
i.e., triacylglycerol, in natural fats of animal and plant origin.
Two distinct families of essential fatty acids exist in the
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human body: the ω-3 family (derived from α-linolenic acid)
and ω-6 family (derived from linoleic acid) 1 .
Phytosterols are a group of natural compounds found in
all plants and in food products of plant origin. In vegetable
oils, sterols are found primarily as free and esterified forms 2 .
Four edible oils: walnuts, sesame, peanut and poppy
seed oil, processed by minimal technologies (cold pressing)
in Romania were investigated. The goal of the present study
was the identification and quantification of fatty acids as
FAMEs (fatty acid methyl esters), in the total lipid extracts
(TLE) and in the esterified sterol fractions (ESF).Total, free
and esterified sterols were also quantified as trimethylsilyl
ether derivatives (TMS), using gas-chromatography (GC)
with flame ionization detector (FID).
Experimental
S a m p l e P r e p a r a t i o n
The FAMEs were prepared by transesterification of
the oil samples and the esterified sterol fractions by sodium
methoxide catalysis1 .
Saponification, extraction, purification and preparation
of TMS derivatives of the total, free and esterified sterols
were made according to Phillips et al. 3 .
Fig. 1. The fatty acid compositions [weight %] in total lipid extracts (TLE) and esterified sterol fractions (ESF) of: (a) walnut,
(b) sesame, (c) peanut and (d) poppysed oils