Utjecaj mikrovalnog zagrijavanja i dodatka antioksidansa na održivost ekstra djevičanskog maslinovog ulja sorte Oblica

Abstract

Virgin olive oil has a high resistance to oxidative deterioration due to both a triacylglycerol composition low in polyunsaturated fatty acids and a group of phenolic antioxidants composed mainly of polyphenols and tocopherols. This essay discusses the effect of microwave heating on the oxidative stability of extra virgin olive oil with or without the addition of antioxidants and synergists. Of natural antioxidants are used rosemary extract and green tea extract and citric acid synergist. Oil samples with or without the addition of antioxidants and synergists were heated in a microwave oven at a constant power of 300 W over a different time period (5, 10, 15 and 20 minutes). Samples were also heated at different power levels (180, 300, 450W) in a constant time period of 5 minutes. The result of the accelerated oxidation test of olive oil is expressed by the peroxide number. Microwave heating of the samples during a longer heating time increases the temperature and the value of the peroxide number, which results in an increase in oxidative oil degradation. Addition of antioxidants and synergists increased the stability of olive oil. The highest stability of extra virgin olive oil was achieved by a combination of green tea extract and synergistic citric acid.