Substituição de antioxidante sintético por pólen no desenvolvimento de suco concentrado de limão

Abstract

Brazil stands out as one of the world's leading citrus producers, and global consumption of these fruits has increased, creating opportunities for market expansion. However, fruit juices rich in vitamin C have been subject to degradation by oxidation and light exposure, reinforcing the importance of proper storage conditions. In this context, ascorbic acid served as an essential indicator of juice quality, with values between 0.17 and 0.24 mglmL in the samples analyzed. The characteristic bitterness of citrus juices was associated with the presence of limonoids. This study evaluated the application of pollen as a natural antioxidant in concentrated lemon juice, aiming to identify alternatives to synthetic antioxidants. Five samples were analyzed, including two controls and three pollen concentrations. The analyses comprised centesimal composition, antioxidant activity, and physicochemical parameters. Limonin content increased at 4 °C in all samples after 28 days, indicating compound formation even under refrigeration. In contrast, at 20 °C a strong reduction was observed—especially in C+ (-61.9%) and C-(-51.3%)—suggesting higher degradation at room temperature. At 40 °C, significant losses also occurred, confirming the thermal instability of the compound. Phenolic contents ranged from 256.32 to 516.94 mgGAE/mL, while flavonoids varied from 39.94 to 194.54 mgQE/mL, both showing correspondence with antioxidant activity. Overall, pollen demonstrated potential as a natural substitute for synthetic antioxidants in concentrated lemon juice.