Juice components and antioxidant capacity of four Tunisian Citrus varieties.
BACKGROUND
Juices from four Citrus species of Tunisia were investigated mainly for quality parameters and antioxidant capacity.


RESULTS
Citrus reticulata (mandarin) juice had the highest content of total flavonoids (85.33 mg CE L(-1)). The latter also occurred in high quantity (82.01 mg CE L(-1)) in Citrus lemon (lemon) juice which was also marked by its richness in total aroma (70.16 µg mL(-1)) and in total fatty acids (48.10 µg mL(-1)). Mandarin and lemon juices had the highest antioxidant activity, as determined b the β-carotene bleaching assay (26.67% and 22.67%, respectively). Citrus aurantium (bitter orange) juice was characterised by the highest content of total polyphenols (784.67 mg GAE L(-1)) and by the greatest inhibition of DPPH (96.10%). Citrus sinensis (blood orange) juice was only marked by the high quantity of ascorbic acid (36.90 mg mL(-1)). GC/MS analysis of juice aroma showed the predominance of limonene (48.85-69.59%) in mandarin and in bitter and blood oranges, but of camphene (89.05%) in lemon. GC analysis of juice fatty acids revealed their richness in oleic acid (23.13-39.52%). HPLC analysis of juice phenolics indicated the predominance of phenolic acids (73.13-86.40%).


CONCLUSIONS
The Citrus species used in this study were considered valuable varieties from the point of view of antioxidant capacity and nutrition.
Tounsi
Moufida Saidani
MS
Unité des Plantes Aromatiques et Médicinales, Centre de Biotechnologie au Technopôle de Borj-Cédria (CBBC), Hammam-lif, Tunisia. moufidatounsi@yahoo.fr
Wannes
Wissem Aidi
WA
Ouerghemmi
Ines
I
Jegham
Sabrine
S
Ben Njima
Yosra
Y
Hamdaoui
Ghaith
G
Zemni
Hassene
H
Marzouk
Brahim
B
D000975:Antioxidants / Q000032:analysis*; D001205:Ascorbic Acid / Q000032:analysis*; D001628:Beverages; D002957:Citrus / Q000737:chemistry* / Q000145:classification; D005419:Flavonoids / Q000032:analysis*; D005638:Fruit / Q000737:chemistry* / Q000145:classification; D008401:Gas Chromatography-Mass Spectrometry; D009812:Odorants / Q000032:analysis; D019301:Oleic Acid / Q000032:analysis*; D010636:Phenols / Q000032:analysis*; D028321:Plant Preparations / Q000737:chemistry; D059808:Polyphenols; D019207:beta Carotene / Q000032:analysis*
D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D028321:Plant Preparations; D059808:Polyphenols; D019207:beta Carotene; D019301:Oleic Acid; D001205:Ascorbic Acid