Antioxidant Activity of Citrus nobilis var Microcarpa and Citrus aurantifolia Hard Candy

In Indonesia, Pontianak oranges and limes are commonly consumed as food and used in traditional medicine, with their antioxidant compounds that contribute to the protection of body cells from oxidative stress caused by free radicals. This research aimed to assess hard candy formulations using hedonic evaluation and to analyze the antioxidant activity of a blend of Pontianak oranges and limes. The evaluation comprised weight uniformity, stability, sugar reduction, and antioxidant activity analysis using the ABTS method. Antioxidant testing of Pontianak orange and lime juice was conducted using three formulations with ratios of 2:3 (F1), 3:2 (F2), and 1:1 (F3). The antioxidant activity values of the fruit juice formulations F1, F2, and F3 were 75.254 ppm, 87.141 ppm, and 79.223 ppm, respectively. In contrast, the corresponding hard candy formulations exhibited antioxidant activity values of 171.863 ppm, 209.729 ppm, and 180.805 ppm. The hard candy met the weight uniformity criteria, with no samples exceeding a 5% deviation from the average weight. The formulations were stable at temperatures of 8–15 °C, with reducing sugar contents of 11.170%, 11.726%, and 11.377%.