ABSTRACT
BACKGROUND: Shiikuwasha (Citrus depressa Hayata) juice from four main cultivation lines subjected to two peeling practices (with or without peeling) were discriminated in terms of quality attributes, represented by sugar and organic acid composition, taste characteristic, aroma profile, and antioxidant activity. RESULTS: Shiikuwasha juice from these lines had diverse food compositions; 'Izumi kugani' juice had lower acidity but contained more ascorbic acid than that of other cultivation lines. The composition of volatile aroma components was influenced by fruit cultivation line, whereas its content was affected by peeling process (20.26-53.73 mg L(-1) in whole juice versus 0.82-1.58 mg L(-1) in flesh juice). Peeling also caused Shiikuwasha juice to be less astringent and acidic bitter and to lose its antioxidant activity. Moreover, the total phenolic and ascorbic acid content of Shiikuwasha juice positively influenced its antioxidant activity. CONCLUSION: Each fruit cultivation line had a distinct food composition, taste characteristic, and aroma profile. Peeling in Shiikuwasha juice production might reduce aftertaste, and thus might improve its palatability. Comprehensive information on the effect of cultivation line and peeling on quality attributes will be useful for Shiikuwasha juice production, and can be applied to juice production of similar small citrus fruits.
