This study was carried out to determine the effects of fermentation on the physicochemical properties and antioxidant activities of noni extract. The analyses carried out included pH value, titratable acidity, total soluble solid (°Brix), total phenolic content (TPC) and free radical scavenging ability (DPPH) involving short (0, 1 and 2 weeks) and long (4, 6, 8, 10 and 12 weeks) period fermentation. For short period fermentation, the results showed that pH value and free radical scavenging ability (DPPH) was significantly (p<0.05) decreased compared with fresh noni extract. The pH value, TPC and scavenging activity of radical DPPH decreased significantly (p<0.05) while titratable acidity increased significantly (p<0.05) for the long period fermentation. The results obtained from this study showed the pH value, titratable acidity, total phenolic content and antioxidant activity were significantly different after fermentation except for total soluble solid. Based on the results, fermentation of noni fruit do not give positive effects on noni extract where fermentation obviously leads to reduction of antioxidant activities.
Keywords: Antioxidant; fermentation; Morinda citrifolia L.; physicochemical properties