Chapter 45 - Cold pressed grapefruit (Citrus paradisi L.) oil

Abstract

Citrus fruits are one of the world’s most popular, easily accessible, nutritiously desirable, and healthy fruits. Citrus varieties are accepted as a rich source of mainly vitamin C, folate, tocols, fiber, and bioactive compounds such as flavonoids, carotenoids, phenolic acids, and limonoids. Lemon (Citrus limon), orange (Citrus sinensis), grapefruit (Citrus paradisi), shaddock (Citrus maxima), tangerine (Citrus reticulata), citron (Citrus medica), and key lime (Citrus aurantifolia) are commonly known popular citrus varieties belonging to the Rutaceae family. Citrus peels, seeds and pulps as by-products, which represents 50% of the raw fruit, are considered unique sources of fixed and essential oils. When considering the aroma characteristics and volatile compositions of essential oils, citrus essential oils were identified as having an important role as a flavoring agent for food, cosmetic, aromatherapy, and pharmacology. Cold pressing is a widely used technique for extraction of citrus essential oils as well as the steam distillation technique, and cold pressed citrus oils have been classified as generally recognized as safe (GRAS). Cold pressed grapefruit oils have a characteristic bitter taste and distinct aroma that can be obtained from grapefruit peel, leaves, or seeds. Due to their great distinctive and nutraceutical composition, numerous studies have indicated the biological activities of cold pressed grapefruit oils. This chapter presents the current scientific knowledge on the cold pressing technique for extraction of grapefruit oils, focusing on compositional properties, bioactive components, volatile compounds, sensory attributes, and beneficial health effects of cold pressed grapefruit oils.