Phenolic Compounds Found in Citrus Species

Citrus fruits contain many components that are beneficial for health, including minerals, vitamins and dietary fibers. They are also the main source of many bioactive compounds with disease-preventing properties, such as flavonoids and limonoids. Flavonoids are a group of pigments found in plants and are responsible for the coloring of flowers and fruits. The richest source of flavonoids in food is fruits and vegetables. The inedible parts of citrus fruits, such as the juice and pulp of the fruit, are as rich in phenolic compounds as the edible parts of the fruit. Citrus peels and seeds are very rich in phenolic acids and flavonoids, and the peels contain more flavonoids than the seeds. The waste parts of citrus fruits, such as peels and seeds, are especially rich in flavonoids and phenolic compounds, and these compounds have important properties for health. Recycling the millions of tons of citrus waste released worldwide has significant potential in environmental and economic terms. Recovery of secondary metabolites from peels contributes to the prevention of chronic diseases as a natural antioxidant source, while reducing oxidation in foods and has the potential to extend shelf life. The phenolic and flavonoid content of citrus waste varies depending on the species, growing conditions and harvest time. The use of citrus waste in food, cosmetics and pharmaceutical industries not only reduces environmental pollution but also enables the development of value-added products in terms of health and nutrition.