The comparison of thermooxidative stability of rapeseed and palm oils during French fries deep-frying
International Conference on Food Safety and Regulatory Measures
August 17-19, 2015 Birmingham, UK

Magda Anio�?owska

Wroc�?aw University of Environmental and Life Sciences, Poland

Posters-Accepted Abstracts: J Food Process Technol


The aim of the research was to compare the thermooxidative stability of rapeseed and palm oils used as frying media in cyclic French fries deep-frying. The materials used for study were refined palm and rapeseed oils and prefries frozen French fries. The experiment was of five days�?? duration and entailed the following: French fries were fried�?? for 8 hours/day in oils heated to 180�?C in 30 minutes cycles. In fresh and after every 8 hours of frying, the oils were analyzed for acid and anisidine values, color, refractive index, fatty acid composition, content and composition of polar fraction. Hydrolysis occurred most intensively in palm oil while oxidation was reported for rapeseed oil. The color of all oils underwent darkening with the largest changes in rapeseed oil. The degradation of oil caused increased change in the RI of frying oils which occurred to the same extent in both frying media. The losses of linoleic fatty acid were observed in all samples with the largest share (22%) in degraded palm oil. The content of total polar compounds increased and the pace of formation depended on frying medium. The total polar content during frying in rapeseed oil was 21.5% and in palm oil 22.9% at the end of frying time. The predominant fraction in fresh palm oil was oxidized triacylglycerols with the presence of diacylglycerols and free fatty acids while in rapeseed oil significantly prevailed diacylglycerols. During frying, new polar compounds were formed including oligomers which were at the highest level in palm oil after 40 hours.

Biography :

Magda Anio�?owska has completed her Master’s studies in Biotechnology from Wroc�?aw University of Technology. In 2011 she started PhD in Food Technology at the Department of Food Storage and Technology. She was also an exchange student in Estonian University of Life Sciences (EMU) from June to September 2014 and Friedrich- Alexander University of Erlangen-Nuremberg (FAU) from February to May 2015. She conducts research on the influence of technological parameters of frying on the content of glycidyl esters in oils and fried foods.