Photolysis:
Grease and volatile organic compounds are easy attacked by UV-C. O2 + hv 
O+O 2 O3 H2O + hv OH + H OH + HO2 The double bonds of the long-chain molecules VOC are destroyed.
Ozonolysis:
Ozone and OH can react with organic compounds and alters them. This reduces the odour containing compounds produced during the cooking process.
