The preparation of a new type of derivatives of the naturally occurring antioxidant hydroxytyrosol is reported. Hydroxytyrosyl alkyl ethers were obtained in high yield by a three-step procedure starting from hydroxytyrosol isolated from olive oil waste waters. Preliminary results obtained by the Rancimat method have shown that these derivatives retain the high protective capacity of free hydrox...

The dried aerial parts of the mountain tea Sideritis euboea were extracted using n-hexane, methanol, diethyl ether, ethyl acetate, and n-butanol. The residues were tested for their antioxidant activity on sunflower oil at 50 degrees C under UV light. The oxidation of the sunflower oil was measured using PV, absorbance E(1%)1 cm, and malondialdehyde by high-performance liquid chromatography (HPL...

In this chapter selected methods used in plant lipid analyses are discussed. The first step of fat analysis consists in the isolation of lipid components from the plant matrix, thus in the first section the most popular methods of isolation are described. Afterwards, due to the complicated mixture of lipid components their separation is required where different types of chromatography technique...

Rapeseed contains high amounts of phenolic compounds, mainly derivatives of sinapic acid, but only a small part can be found in virgin rapeseed oil, since the polar compounds remain in the press cake. A temperature treatment of the raw material results in the degradation of sinapic acid to 2,6dimethoxy-4-vinylphenol (vinylsyringol or canolol), which is described in literature as a very strong a...

Abstract—Biodiesel is one of the alternative fuels that promising for substituting petro diesel as energy source which is advantage on sustainability and ecofriendly. Due to the raw material that tend to decompose during storage, biodiesel also have the same characteristic that tend to decompose and formed higher acid value which is the result of oxidation to double bond on a chain of ester. De...

The aim of this work was to compare the positional fatty acid composition, sterols, tocopherols and oxidative stability of mustard oil (MO) and rapeseed oil (RSO). The MO contained higher levels of erucic acid (42.8%) and linolenic acid (18.2%), compared with RSO (0.4 and 8.6%) whereas the RSO contained higher levels of oleic acid (62.2%) and linoleic acid (19.5%), than that of MO (17.4 and 15....

Two Marula, Sclerocarya birrea seed samples originating from Western Sudan, were analyzed, and the characteristics and constituents of the kernel oils were determined, including physico-chemical properties, specific gravity, oil colour, refractive index, saponification value, unsaponifiable matter, acid value, free fatty acids, and phosphorus content. Total fatty acid compostion was determined ...

ABSTRACT Oil blending is often used to enhance the properties of vegetable oils. The admixture of a more thermally stable oil makes the resulting blend more suitable for use in frying. A new method of quality assessment of vegetable oils used in frying is presented in this paper. In this method, ultra-fast gas chromatography coupled with flame ionization detector and chemometrics is employed. P...