Effect of UV on Food Components and Quality
UV light exposure initiates free radical oxidation and catalyzes other stages of the oxidation process. Lipid radicals, superoxide radicals (SOR), and H2O2 are formed due to UV light (Kolakowska 2003). SOR can further induce carbohy-drate cross linking, protein cross linking, protein fragmenta-tion, peroxidation of unsaturated fatty acid, and loss of membrane fluidity function. Denaturation of components such as proteins, enzymes, and amino acids (especially amino acids with aromatic compounds) in milk may occur with UV radiation, thereby also bringing about textural changes. Water also absorbs UV photons and produces OH- and H+ radicals, which in turn aids changes in other food components. Kolakowska (2003) reported that there are obvious changes in the chemical composition of food com-ponents and product quality deterioration when the UV light treatment is applied in high doses. Therefore, it is mandatory to properly optimize the disinfection process so that the quality of the food products is maintained and its safety is ensured. Normally, microbial inactivation can be achieved within seconds to minutes depending upon the opacity of the food products and microorganism type. In general, using UV light treatment for food has been found not to cause any adverse effects, especially if UV light is applied in moderate amounts (Krishnamurthy 2006). However, the modification and optimization of the UV light treatment might be necessary for successful implementation of the process with regard to some foods.
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