Changes in citrus-based fruit wine during storage

Purpose : The purpose of this study was to prepare two types of fruit wine with 10% and 20% peel using three types of citrus from Kagoshima Prefecture (Beni-amatsu, Kawachi-bankan, and Fukiage-konatsu), and to explore changes over time after preparation.
Methods：Fruit wine was prepared using fruit, fruit peel, glacial sugar, and white liquor. The peels and fruit were removed from the fruit wine at 4 weeks after pickling, and the color difference, acidity, sugar content, and pH were measured thereafter until the 20th week. Fruits and peels removed from fruit wine were freeze-dried and extracted with 35% and 70% ethanol, and the total polyphenol content and DPPH radical scavenging capacity were determined along with the fruit wine.
Results：The fruit wine with 20% fruit peel showed higher L*, a*, and b* values than the wine with 10% fruit peel, but the acidity, sugar content, and pH showed little difference due to the amount of fruit peel. L*, a*, and b* values and acidity increased and sugar content decreased until the fourth week after
pickling, but remained almost unchanged after the fruit and peel were removed at the fourth week. The total polyphenol concentration in the fruit wine was higher in fruit wine with 20% fruit peel than in fruit wine with 10% fruit peel for all citrus, and remained unchanged after the fourth week. The DPPH radical
scavenging capacity of fruit wine with 20% fruit peel was higher than that of wine with 10% fruit peel and remained flat or decreased after the 4th week.