# Effects of the Extraction Technology on Pomegranate Juice Quality
## 3 Results and Discussion  
Figure 6 shows that the arils obtained at the end of the process for juice extraction are headless and free of liquid. The processing line allowed to extract all the juice content of the fruit. The yield of extracted pomegranate juice resulted 33.5% \(\pm\) 2.0. The yield values were similar to those obtained by [PERSON] et al., i.e., 39.2% ([PERSON] et al., 2015), while in [PERSON] et al. ([PERSON] et al., 2014), it ranged from 42.9 to 61.4%. The total yield of 33.5% was distributed as follows: 8.4% in T1, 3.3% in T2, 5.3% in T3, 4.0% in T4, 2.4% in T5, 2.7% in tests T6, T7 and T8 and 2.0% in T9 revealing a progressively lower amount of extracted water during the process. Table 2 shows pH, Total Soluble Solids (TSS), Titratable Acidity (TA), Total Phenolic Content (TPC), Radical-Scavenging Activity (RSA) and Total Anthocyanins (T ANT) values of pomegranate juice samples obtained with different pressures of the pneumatic press during the tests. Figure 6: Arils after pressing performed with the F22 pneumatic press by Puleo Srl, Marsala (Italy). The qualitative parameters of the juice are subject to natural fluctuations caused by the variety, the ripening index, the geographical site and climatic conditions of cultivation and conservation of the fruits before their processing [21; 22]. Table 2 shows the main quality parameters of pomeranate juice in the various tests; pH remains almost stable with values between 3.04 and 3.18. It resulted similar to that measured from the juice of the same cultivar by [PERSON] at al., ranging from 3.41 to 3.86 [16] and by [PERSON] et al., ranging from 1.85 to 3.23 [17]. The TSS values are around 14.0 \({}^{\circ}\)Brix in all the tests except T1 and T8 (15.2 and 17.0 \({}^{\circ}\)Brix respectively). The averaged value resulted similar to that measured by [PERSON] et al., ranging from 14.3 to 15 \({}^{\circ}\)Brix [16], and slightly lower than that obtained by [PERSON] et al., ranging from 16.03 to 16.34 \({}^{\circ}\)Brix [17], both from the juice of the same cultivar surveyed in this work. The value of total acidity (titratable acidity) in fruit juices depends on the organic acids of the fruit. The TA values are between 1.58% and 1.86% in the different tests. The averaged value (1.72%) resulted similar to that measured by [PERSON] et al., ranging from 1.53 to 1.78%, from the juice of the same cultivar (i.e., Wonderful One) [17]. pH, TSS and TA values are also similar to those obtained by [PERSON] et al. [23]. TPC values obtained are gradually increasing from T1 (694 mg g\({}^{-1}\)) to T9 (1076 mg g\({}^{-1}\)) with statistically significant differences. They exclusively refer to the juice, because the plant used has eliminated the skins by means of the shelling machine. Some results obtained by other authors, on the other hand, show a higher TPC content since their pressing phase also takes into consideration the peel of the fruit which contains a high polyphenols content. Indeed, [PERSON] et al. [24] studied four pomeranate cultivars obtaining from the skin TPC values from 1775.4 to 3547.8 mg g\({}^{-1}\) while in juice and arils they found values from 784.4 to 1551.5 mg g\({}^{-1}\) and 117.0 to 177.4 mg g\({}^{-1}\) respectively. As for RSA values, there is an increase of about 23% from T1 to T9, with an average value of 72.94%. The averaged value resulted much higher than that measured by [PERSON] et al. [12], ranging from 17.2 to 39.1%, from the pomeranate juice of four different ecotypes. Finally, the highest T ANT value is obtained in T1 (552 mg L\({}^{-1}\)) while in the other tests there is approximately a 40% decrease. Anthocyanins are present in considerable quantities in the skins [25; 26; 27], and this justifies the higher value of T ANT in T1 and the subsequent decrease in the following steps in which pressure is applied in order to extract the juice only from the arils. The average value extracted from the above juice resulted similar than that measured by [PERSON] et al. from the commercial pomeranate juice, i.e., 387.4 mg L\({}^{-1}\)[11].