Development and quality assessment of new drinks combining sweet and sour pomegranate juices

Abstract

This study was carried out to evaluate the physicochemical properties and the suitability of some parameters for the design of a new beverage combining sour and sweet pomegranate juices as an alternative use for neglected varieties. Sweet pomegranate juices from varieties Zaghouani and Tounsi and sour juices from varieties Mezzi and Garsi were used in this study. Higher titratable acidity (1.6% calculated as citric acid) with a pH of 2.73- 2.82 was registered in Garsi and Mezzi juices. The contents of ascorbic acid, anthocyanins and total phenols were in general high, 20-25 mg ascorbic acid, 37.7-56 mg cyanidin and 164.4-181.8 g gallic acid per 100 ml juice, respectively. Zaghouani and Mezzi varieties gave the cleanest juices, while Tounsi gave the less colored juice. The highest antioxidant activity was registered in sour varieties. New polyphenol-rich beverages were prepared using sour and sweet pomegranate juices in different proportions (reaching pH 4.0). The results of sensory tests suggest that mixed beverages are preferred to pure sweet juices. Garsi (18.2%)-Zaghouani (81.8%) mixture provided the most appreciated beverage with good organoleptic properties (color, clarity and flavor) followed by Garsi (16.7%)-Tounsi (83.3%) mixture which was well appreciated for its taste and improved color. Further research is needed to establish new pomegranate juice combinations and to examine the stability of characteristics and bioactive proprieties of mixtures after cold storage in order to develop new healthy beverages.