In vitro investigations of Cumin oil as antioxidants agent on fresh and fried edible oil

Abstract

This study was designed to determine the effect of cumin oil as antioxidant on the chemical properties of stored sunflower oil. The study is complementary to a previous study in which cumin oil was used to demonstrate its effect on fried sunflower oil. Two samples of sunflower oil were subjected to chemical tests before and after the addition of cumin oil. In addition, four equal samples in volume of sunflower oil were prepared and then the following steps were made, nothing on the first sample, the second sample was transformed into a water bath at the boiling point for 20 min, to the third sample cumin oil added, and in the fourth both process addition and boiling occurred. Also two of fried sun flower oil of taameia and fish was prepared in the same above volume after purification and filtration, after that to both samples cumin oil was added separately. The six samples were then transferred to a storage environment similar to that in the local market in Shendi area for a period of time from 10 October 2017 to 10 April 2018. At the end of storage the samples were investigated to assess their chemical properties. The results showed adifference in the values of the properties, where there was a clear decrease in the values of peroxide and acidity, while an increase in the saponification value was observed and this may be attributed to antioxidant compounds in cumin oil, reaction between hydroxyl group compounds of cumin with acid groups of sample oil which lead to decline carboxyl groups in oil, and could be due to increase of ester formation result from previous reactions respectively for three chemical properties. In addition, the investigations resulted in a clear reduction in the peroxide value of the mixtures oil compared with pure sunflower oil and unexpectedly for the temperature, the boiling of fresh and mixture oil before storage had appeared a decrease in peroxide value.