The TBARs value reflects the quantity of malondialdehyde produced as a result of the subsequent breakdown of lipid hydroperoxides. The TBA reactive compounds value is the primary indicator of additional milk fat oxidation in the system (Guillen-Sans and Guzman-Chozas, 1995). At two different exposure doses (control, 279, and 838 mJ/cm 2 ), all samples were evaluated for the formation of TBARs substances. The TBARS test primarily measures malondialdehyde, a secondary oxidation product, and reports result in milligrams per kilogram of the sample (Fig. ). Whole milk exposed to UV-A irradiation at an intensity of 838 mJ/cm 2 had a higher TBARS value (0.167±0.02 mg MDA/L) than the control (0.152±0.01 mg MDA/L). It is interesting to note that milk treated at 279 mJ/cm 2 had lower levels of oxidation (0.149±0.04 mg MDA/L) than the control. Although there was a 9.9 % increase in TBARS value between control and 838 mJ/cm 2 irradiation, this difference was not significant (p>0.05).