K. ALEKSIEVA1, I. NACHEVA2, K. DIMOV2 and Tsv.TSVETKOV2
1 Bulgarian Academy of Sciences, Institute of Catalysis, Molecular Catalysis with Center of EPR spectroscopy, BG-1113 Sofi a, Bulgaria
2 Agricultural Academy, Institute of Cryobiology and Food Technologies, BG-1407 Sofi a, Bulgaria
ALEKSIEVA, K., I. NACHEVA, K. DIMOV and Tsv. TSVETKOV, 2016. Natural and gamma induced free radicals in dried fruits. An EPR study. Bulg. J. Agric. Sci., 22: 1010–1013
The aim of the present study is to prove radiation processing in air dehydrated dates, prunes and fi gs, as well as to recommend which part of the fruit to sample. The detection method is Electron Paramagnetic Resonance (EPR) spectroscopy. Before irradiation in date stone, prune stone and fl esh, and fi g seeds EPR spectroscopy was detected a weak singlet line, whereas date flesh and fi g fl esh are EPR silent. After gamma-irradiation in date stone and fl esh, and fig flesh a “sugar-like” EPR spectrum is recorded. In prune stone a typical “cellulose-like” spectrum is detected, whereas in prune flesh and fig stone only singlet line is recorded as before radiation treatment. Of research done it can be seen that the irradiation is proved in a different part of the fruit. European Protocol EN 13708 is applicable to irradiated dried dates and fi gs, whereas Protocol EN 1787 for dried prunes.