Effect of biogenic amines on the oxidation of vegetable oils determined by rancimat assay

V okviru diplomske naloge smo z metodo Rancimat v lanenem in sončničnem olju preverjali antioksidativen učinek izbranih biogenih aminov (spermina, spermidina in tiramina) v koncentraciji 1 mmol/kg, antioksidativen učinek spermina v koncentracijah 1 mmol/kg, 0,4 mmol/kg in 0,1 mmol/kg ter rezultate primerjali z učinkom izbranih antioksidantov (alfa-tokoferol, gama-tokoferol in BHT) v koncentraciji 1 mmol/kg. Vsi dodatki so podaljšali obstojnost olja. Laneno olje oksidira hitreje kot sončnično, saj ima večji delež večkrat nenasičenih maščobnih kislin, predvsem alfa-linolenske. Ugotovili smo, da so biogeni amini pri koncentraciji 1 mmol/kg boljši antioksidanti kot izbrani fenoli in BHT. Najmočnejši antioksidativni učinek smo določili za spermin, ki je upočasnil oksidacijo olj tudi pri najmanjši dodani koncentraciji 0,1 mmol/kg. Te ugotovitve bi lahko imele praktično uporabnost v živilski industriji, vedno več raziskav se namreč osredotoča na iskanje naravnih spojin z antioksidativnim učinkom.In the Bachelor thesis we tested the antioxidative effect of the biogenic amines (spermine, spermidine, tiramine) at the concentration of 1 mmol/kg, antioxidative effect of spermine at the concentrations of 1 mmol/kg, 0,4 mmol/kg, 0,1 mmol/kg and compared the results with the effect of alpha-tocopherol, gamma-tocopherol and BHT at the concentration of 1 mmol/kg in flaxseed and sunflower oil with the Rancimat method. All additions resulted in improved oil stability. Flaxseed oil oxidizes faster than sunflower oil because it contains more polyunsaturated fatty acids, especially alpha-linolenic acid. We concluded that biogenic amines are better antioxidants compared to phenolic compounds alpha- and gamma-tocopherol and BHT at 1 mmol/kg concentration. Spermine was determined to be the strongest antioxidant used in the experiment and it shows the antioxidative effect even at the concentration of 0,1 mmol/kg. Those findings could have the practical implications in food technology as recently many research is focused on finding natural compounds with antioxidative effect