In the course of this graduation thesis we compared total phenolic compounds and antioxidant activity in fresh squeezed pomegranates juice. We found differences between manual and machine-squeezed juice and between juices of diferent origin (Turkey, India). In the manual preparation of the sample we only pressed the juice from the arils without damaging the seeds, while in the mechanical mode, the seeds were damaged. Total phenolics were determined spectrophotometrically by means of Folin–Ciocalteu method and antioxidant activity with the free radical DPPH· assay. There was no significant difference between Turkish and Indian pomegranate in any of the analysed parameters, while the statistically significant differences were determined in differently squeezed juices (manually, machine). Manually squeezed juices had higher levels of total phenolic compounds, (6.8 ± 1.3) mM, and antioxidant efficiency, (8.1 ± 2.0) mM, compared with the machine-squeezed juices that had (5,7 ± 1,0) mM of total phenolic compounds and antioxidant efficiency (5,7 ± 1,3) mM. The obtained values of the total phenolic compounds are lower in comparison with the Fischer study et al. (2011), which can be attributed to differences in the design of the experiment. Antioxidant activities were compared to studies performed by Gil and et al. (2000), Mousavinejad et al. (2009) and by Fischer et al. (2011) quite similar.
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