PL
Praca jest kontynuacją badań nad skutkami napromieniowania olejów jadalnych - palmowego, słonecznikowego, lnianego i kokosowego. Oznaczono rozpad natywnych tokochromanoli, zmiany składu kwasów tłuszczowych i ich oksydację oraz obliczono współczynnik Harrisa. W części I opublikowanej w kwartalniku „Bromatologia i Chemia Toksykologiczna", 1996; 19: 63-70, omówiono wpływ promieniowania Co-60 na oleje - złocisty, sojowy i rzepakowy.
EN
Effects of Co-60 gamma irradiation on the quality of palm, sunflower, linseed and coconut cooking oils were studied. Dissolution of tocochromanols, changes in fatty acid amounts and their oxidation, and Harris coefficient were determined. Oil samples were irradiated in a PXM Gamma Co-60 radiation apparatus. Radiation doses were determined by Frick dosimetry. The results did not reveal particular sensitivity of the test oils to the gamma radiation as evidenced by the values of radiation efficiency (G) which were within the range typical of food chemical components, including also vitamin E. Significant degradation of PUFA in the test oils was not observed. Increasing radiation doses caused a reduction of fatty acid percentages in coconut and palm oils, while fatty acid levels of sunflower and linseed oils were not affected. Increased radiation doses resulted in lower values of Harris constant, particularly in linseed and sunflower oils, whereas the high peroxide value in all test oils at 2.5 kGy caused that they were no longer suitable for eating.