## 3 Results
### Optimization of Parameters and Design Checks in UV Processing  
The responses obtained from 12 samples with UV pasteurization according to the experimental design are given in Table 2. The results showed that the TPC amounts, turbidity values, \({}^{\circ}\)Brix values, color a* values, and yeast and mold count at the experimental points were ranged from 840 to 1060 mg GAE/L, 3.59 to 4.61 NTU, 14-16 \({}^{\circ}\)Bx, 2.3 to 2.5, and \(<\)0.5 to 3.92 log CFU/mL, respectively. ANOVA analysis of the data obtained from the experimental design and the interaction of the factors with the responses are given in Table 3. The results showed that temperature and flow rate parameters were statistically significant for the amount of yeast and mold, and the UV dose was not statistically important. Considering the results, the increase of the UV dose would decrease the microbial growth at 40 \({}^{\circ}\)C and 50 \({}^{\circ}\)C temperature applications. The microorganism growth is under the detection limit because of the simultaneous UV application at 60 \({}^{\circ}\)C. Since the microbial growth was already undetectable at this temperature, the intensity of the UV dose applied was statistically insignificant. UV treatment resulted in an average of 1-2 log reduction of the yeast and mold count. The value of R\({}^{2}\) was 0.999, showing a strong linkage between the independent parameters and the responses. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**TPC** & **Turbidity** & \({}^{\circ}\)**Brix Value** & **Color a*** & **Yeast and Mold Count log CFU/mL** \\ \hline
1078 \(\pm\) 5.72 & 4.2 \(\pm\) 0.19 & 14 \(\pm\) 0.0 & 2.3 \(\pm\) 0.0 & 5.3 \(\pm\) 0.1 \\ \hline \hline \end{tabular}  
* The values are expressed as mean \(\pm\) standard deviation (replications = 3).  
\end{table} 
Table 1: Result for total phenolic content (TPC), turbidity, \({}^{\circ}\)Brix, color a*, and yeast and mold count of unprocessed pomegranate juice. Temperature, flow rate, and UV dose parameters were not statistically significant (\(p>0.05\)) when the TPC amount of samples treated with UV was considered. Even though the effect of the temperature, flow rate, and UV dose on TPC values in the UV pasteurization process was not statistically significant, the TPC amount of samples decreased. Phenolic compounds are adversely affected and reduced at higher temperatures and UV doses. The \({}^{\circ}\)Brix value increased due to the increase in temperature, which is statistically significant (\(p<0.05\)) while the effects of other factors on the \({}^{\circ}\)Brix value of samples are statistically insignificant (\(p>0.05\)). As for the ANOVA test results for turbidity values, only the temperature is statistically significant for turbidity (\(p<0.05\)). The color a* value of samples was not statistically affected by temperature, UV dose, and flow rate (\(p>0.05\)). Optimization tests were performed for yeast and mold count and TPC amount responses in the design. UV applications with the highest temperature (60 \({}^{\circ}\)C), the lowest flow rate (1.5 L/min), and used either 1 lamp or 2 lamps inhibited almost all yeast and mold growth. Even if these conditions were seen as the best condition, the optimum condition was obtained evaluating together with the TPC and yeast and mold count by the design expert program. For the optimization process, although the amount of TPC tended to increase-decrease depending on three factors, it was not statistically affected by low temperature and short processing time.