Botanical Profile
Citrus limon is the lemon, a globally cultivated Citrus taxon with acidic fruits, aromatic peel and an important essential oil. From a raw-material perspective, juice, peel, fruit powder, pectin fractions, essential oil and flower or leaf raw materials must be distinguished.
Citrus limon is an evergreen, usually small tree with glossy aromatic leaves, white to reddish-tinged flowers and oval to elliptical yellow berry fruits. The fruit has an outer oil-gland-rich peel, the yellow flavedo, a white albedo layer and juicy, strongly acidic pulp. Lemon belongs to the complex hybrid group of the genus Citrus; taxonomic treatment can vary by botanical source. In trade, food technology and flavour science, Citrus limon is firmly established as the lemon raw material. Peel, juice and oil differ markedly in composition and use. The peel provides essential oil and flavonoid-rich fractions, while the juice mainly provides acidity, water and soluble constituents.
Phytochemistry
Lemon juice contains mainly water, citric acid, smaller amounts of sugars, minerals, vitamin-C-rich fractions and soluble plant constituents. The peel contains essential oil with limonene as the main component, together with beta-pinene, gamma-terpinene, citral, linalool and other volatile compounds. Flavonoids such as eriocitrin, hesperidin, diosmin and related glycosides occur in peel and albedo. Pectins are obtained technologically from Citrus peels. Lemon essential oil is susceptible to oxidation and, depending on the production method, may contain furocoumarins relevant to phototoxicity, particularly in cold-pressed oils. Cultivar, origin, degree of ripeness, peel treatment, pressing, distillation and storage influence the profile.
Traditional Uses
Lemon is deeply rooted in Mediterranean, Arab, Indian and European culinary and trade contexts. The juice was used as an acidifying food, seasoning and preserving component, while the peel served as an aromatic spice and fragrance raw material. Lemon oil and lemon peel were used in perfumery, confectionery, beverages and household preparations. Culturally, lemon is associated with acidity, freshness, fragrance and maritime trade routes. Traditional uses relate to juice, peel or fragrance fractions and must be distinguished from modern health-related statements or concentrated extracts.
Current Research
Research on Citrus limon addresses Citrus flavonoids, lemon oil, pectins, aroma profiles, fruit-juice chemistry, by-product utilisation, authenticity and safety aspects of essential oils. Limonene-rich peel oils are used technologically and aromatically, while oxidation and sensitisation are relevant issues. Flavonoid fractions are studied analytically and in experimental models. Pectin from lemon peel is an important food raw material. Studies of isolated flavonoids, essential oil or concentrated extracts cannot be transferred directly to lemon juice or culinary use. For raw-material development, residues, peel treatment, oil quality and authenticity are key considerations.
Sources
- Plants of the World Online: Citrus limon (L.) Osbeck; Royal Botanic Gardens, Kew.
- Scientific literature on Citrus limon, lemon oil, Citrus flavonoids and pectins.
- Flavour and cosmetic raw-material literature on lemon essential oil.
Notice
The information presented in this botanical profile has been compiled to the best of our knowledge and belief from botanical, phytochemical, historical and scientific sources. It is intended solely for general professional information and initial orientation.
The content does not constitute an assurance of specific properties, effects, qualities or possible uses of products or extracts. In particular, it does not constitute a guarantee, a statement of suitability, or a statement regarding marketability, permissibility or usability in specific applications or markets.
Assessment of the suitability of a raw material or extract for a particular intended use, as well as compliance with all applicable legal and regulatory requirements, is the sole responsibility of the respective user.