摘要:Natural antioxidants found in plants play an important role in food and cosmetics because there is a trend to use this type of antioxidants. Phenolic acids (hydroxy derivatives of benzoic and cinnamic acids) are well soluble in various systems containing water, however, in bulk oils are limited soluble. Esters of phenolic acids are suitable antioxidants for bulk oil systems. The oxidative stability of the bulk oil systems with selected phenolic acids and their esters was determined by method Rancimat and Oxidgraph and compared with α-tocopherol and butylhydroxytoluene (BHT). The antioxidant activity of gentisic acid, caffeic acid and methyl caffeate is the highest and generally inversely proportional to redox potential of phenolic acids.