Impact microwave heating and the addition of antioxidants on oxidative stability of hazelnut oil

Cilj ovog istraživanja bio je ispitati utjecaj mikrovalnog zagrijavanja na oksidacijsku stabilnost hladno prešanog lješnjakovog ulja tretiranjem pri različitim jačinama i vremenima mikrovalnog zagrijavanja. Također, ispitivan je utjecaj dodatka prirodnih antioksidanasa (ekstrakt zelenog čaja, ekstrakt nara i ekstrakt ružmarina) u udjelu 0,2% te sintetskog antioksidansa (propil galat) u udjelu 0,01% na promjenu stabilnosti ulja. Određivanje oksidacijske stabilnosti lješnjakovog ulja te utjecaj antioksidanasa provedeno je primjenom mikrovalnog zagrijavanja. Rezultati utjecaja mikrovalnog zagrijavanja na stabilnost lješnjakovog ulja prikazani su peroksidnim brojem (mmol O2/kg). Porastom vremena tretiranja lješnjakovog ulja mikrovalnim zagrijavanjem kod konstantne snage uređaja od 300W dolazi do smanjenja održivosti ulja što rezultira porastom peroksidnog broja. Primjenom veće jačine mikrovalnog zagrijavanja dolazi do većeg oksidacijskog kvarenja. Dodatkom prirodnih antioksidanasa i sintetskog antioksidansa dolazi do porasta stabilnosti ulja prema oksidacijskom kvarenju.The aim of this research was to evaluate the influence of microwave heating on the oxidative stability of cold-pressed hazelnut oil treatment at different intensities and times of microwave heating. It also examines the influence of natural antioxidants (green tea extract, pomegranate extract and rosemary extract) in the proportion of 0,2% and synthetic antioxidants (propyl gallate) in the proportion of 0,01% to change the stability of the oil. Determination of oxidative stability of hazelnut oil and the influence of antioxidants was conducted using microwave heating. The results of influence of microwave heating on the stability of hazelnut oil are indicated by peroxide number (mmol O2/kg). Raising the time of the microwave heating treatment for the hazelnut oil at the constant power of 300W devices lead to decreased viability of oil, resulting in the increase of peroxide number. By using a more powerful microwave heating leads to higher oxidative deteriorations. Adding the natural antioxidants and the synthetic antioxidant leads to an increase in oil stability towards oxidative deterioration