ISSN 2456-0235

International Journal of Modern Science and Technology


​​October-November 2021, Vol. 6, No. 10-11, pp. 161-165. 

​​Effect of Repetitive Frying on some Physicochemical Characteristics of four Edible Vegetable Oils

Esam Abdulkader Elhefian¹,²*, Nisreen Miftah Alghrabli¹, Ayyah Saeid Alghanoudi¹
¹Department of Chemistry, Faculty of Science, Sabratha University, Sabratha, Libya.
²Research, Consulting and Training Center, Sabratha University, Sabratha, Libya.

​​*Corresponding author’s e-mail:


Vegetable oils are fats that are extracted from some fruits, seeds and nuts. They have been used for human food as frying and cooking oils. Deep-frying is a method in which food is submerged in hot oil and has become more and more popular in recent years. However, repeated frying of the same batch of oil may lead to oil spoilage, which in turn might cause some negative effects on human health. In this work, some physicochemical properties (density, viscosity and acid value) of four edible vegetable oils were evaluated at room temperature (25±0.1oC) before and after repeated frying five times using potatoes. Generally, statistical analysis showed a significant positive correlation (p˂0.05) between the number of frying times and the studied parameters, especially, for density and viscosity measurements. In addition, Pearson correlation coefficient analysis showed strong positive correlations between every two oils for density measurements while the coefficient values varied between -1 and 1 for viscosity and acid value measurements. It is worth mentioning that the frying process followed in this work is a common practice of Libyan households.

Keywords: Vegetable oils; Deep frying; Physicochemical properties; Statistical analysis.


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