Used cooking or frying oils are of increasing interest as inexpensive feedstock for biodiesel production. In this work, used frying oils obtained from 16 local restaurants were investigated regarding their fatty acid profile vs. the fatty acid profile of the oil or fat prior to use. The fatty acid profiles were analyzed by gas chromatography and proton nuclear magnetic resonance spectroscopy. B...

The frying performance of Moringa stenopetala seed oil (extracted with cold press or n-hexane) was studied especially as regards repeated frying operations. The oils were used for intermittent frying of potato slices and cod filets at a temperature of 175 degrees C for 5 consecutive days (5 fryings per day). The chemical changes occurring in oils were evaluated. Free fatty acid content, polar c...

This study was conducted to investigate the condition of frying oil used for frying chicken nuggets in a deep fryer. The acidification of the frying oils used, soybean oil (SB), canola oil (CA), palm oil (PA), and lard (LA), were determined as peroxide value, acid value, and fatty acid composition, after chicken nuggets were fried in them for 101 times. The acid value and peroxide value obtaine...

Palm oil is shown to have antioxidant, anticancer and cholesterol lowering effects. It is resistant to oxidation when heated compared to other frying oils such as soy oil. When a frying oil is heated repeatedly, it forms toxic degradation products, such as aldehydes which when consumed, may be absorbed into the systemic circulation. We have studied the effects of taking soy or palm oil that wer...

Baking and frying are two common food preparation methods, but there is limited knowledge about the lipid oxidation events that occur in food products prepared in these ways. Two commercially available breaded shrimp products were examined using gas chromatography, for changes in cholesterol, phytosterols, and fatty acids as a result of baking and deep frying after separation into breading and ...

A rapid method for determining the carbonyl value of frying oils has been developed using Fourier-transform infrared (FTIR) spectroscopy and chemometrics. One hundred and fifty-six frying oils with different carbonyl values were collected from an actual potato frying process. FTIR spectra in the range of 4000-650 cm(-1) were scanned with a FTIR spectroscopy apparatus using the attenuated total ...

The production of biodiesel from waste vegetable oil offers a triple-facet solution: economic, environmental and waste management. The new process technologies developed during the last years made it possible to produce biodiesel from recycled frying oils comparable in quality to that of virgin vegetable oil biodiesel with an added attractive advantage of being lower in price. Thus, biodiesel p...

The performance of olive oil during intermittent frying of potato slices and cod fillets was compared to those of selected vegetable oils (corn, oliveresidue and 50/50 mixture of olive and corn oils) using conditions resembling those used in home food preparations. The main scope of this study was to decide what is the best substitute for olive oil in home frying applications. Free fatty acid c...

Headspace gas chromatographic analysis of heated soybean oil was investigated as a tool to determine what effect hydrogenation and additives have on the formation of total and individual volatile components. Soybean oil was hydrogenated to varying linolenate (Ln) contents with either nickel (Ni) or copper catalysts. Oils were stabilized with citric acid (CA) or a combination of CA with tertiary...

There have been many studies involving frying of potato chips in various vegetable oils in order to observe the quality of the fried product [1-6]. Frying oils are exposed to extreme environmental conditions (air, water or steam, high temperatures of 140-200 °C), trace metals that result in degradation of the frying oil triacylglycerols by oxidation, polymerization, isomerization, cyclization a...