Physico-Chemical Characteristics of Pomegranate Harvested in Yamanashi Prefecture in Japan

Abstract

　To elucidate the physico-chemical properties of the juice and the fruit as a whole for pomegranates harvested in the Yamanashi prefecture in Japan compared to that of the imported ones, following analysis were conducted. ① On average, the domestic fruit weight was approximately 150g per fruit, while the aril and juice ratios to the fruit weight were about 60% and 42%, respectively. The juice ratio to the aril weight was approximately 70%. These ratios were lower than those calculated for the imported fruit (approximately 400g per fruit), and not dependent on the fruit size. ② The brix measurement of pomegranate juice from domestic fruit was 17 and the sugar was glucose and fructose, while both ratios were nearly equivalent, it was slightly high in fructose. The same results were obtained for imported fruits. Titratable acidity in the imported fruit was much higher than that in the domestic fruit, which mainly composed of 0.7% oxalic acid. However the organic acid content in the imported fruit was 1.5% citric acid with a small amount of malic acid. ③ The dominant free-amino acids in the juices listed in order of high to low concentration were glutamine, glutamic acid, aspartic acid and serine. There were no significant differences between the juices from domestic And the imported fruit. Small quantities of sarcosine were detected in both juices. ④ Total polyphenol content in the juices was approximately 100mg% and 200mg% in the domestic and imported fruit, respectively. The HPLC analysis of the polyphenol revealed that punicalin and punicalagin were detected in the juices from the domestic fruit and not the imported fruit.