Citral (Geranial/Neral)とは？用途・使用量・代替品・規格

Citral, English name is Citral, also known as 3,7-Dimethyl-2,6-octadienal, is an acyclic monoterpene aldehyde organic compound with a strong lemon aroma. It is one of the most widely used and applied natural terpene aldehydes in the global flavor and fragrance industry, occupying an irreplaceable core application value in the food flavor industry, daily chemical fragrance industry, and pharmaceutical chemical intermediate fields. Its molecular formula is C10H16O, molecular weight is 152.23, CAS number is 5392–40–5, EINECS number is 226–394–6, and FEMA number is 2303. In terms of chemical structure, citral belongs to the acyclic terpene aldehyde class. The natural product is a mixture of two geometric isomers: the trans isomer geranial (Citral a, also known as Geranial) and the cis isomer neral (Citral b). The ratio of these two isomers is approximately 80%—90% geranial and 10%—20% neral. Because the physical properties of the two isomers are similar, they are usually applied in the flavor industry as a mixture. Citral contains a reactive aldehyde group and conjugated double bond structure in its molecule, which not only gives it a strong aroma itself but also enables it to derive a series of high-value-added flavor compounds through reactions such as condensation, cyclization, oxidation, and reduction, including ionone, methyl ionone, damascone, geraniol, nerol, and citronitrile. Therefore, it is known as the pearl in the crown of fine chemicals. Citral naturally occurs in various plant essential oils such as litsea cubeba oil (content approx. 70%), lemongrass oil (content 70%—80%), lemon oil, lime oil, citrus leaf oil, and verbena oil. Citral appears as a colorless to light yellow transparent liquid with a strong, fresh, persistent lemon-like aroma and no optical activity. It is volatile, soluble in most organic solvents such as ethanol, diethyl ether, propylene glycol, glycerol, mineral oil, and vegetable oils, but insoluble in water. Citral is not only the most important main flavorant for lemon-type flavors but also a key intermediate for the synthesis of ionone, Vitamin A, Vitamin E, phytol, and various high-end flavors, holding extremely high economic value and strategic position in both the flavor industry and pharmaceutical chemistry. Because its production process is complex and the product technology is difficult, it is recognized by the industry as the technological high ground in the field of fine chemicals. The product is widely used in daily chemical flavors, food flavors, perfumes, washing products, cosmetics, pharmaceutical intermediates, and natural antibacterial agents.

Citral is recognized as the soul of citrus aroma, holding an unshakable position in the global flavor and fragrance industry, food industry, pharmaceutical chemistry, and daily chemical industry. Its most outstanding advantages lie in its strong, persistent natural lemon aroma, irreplaceability as a key synthetic intermediate, good bioactivity and nature-identical properties, and broad market application prospects. 1 Strong, Persistent Natural Lemon Aroma: Citral is the purest and strongest source of natural lemon aroma in nature. Its aroma is fresh, sweet, and persistent, more natural and mellow than synthetic citrus flavors. This aroma characteristic makes it the core raw material for blending lemon-type, citrus-type, and bergamot-type flavors, widely used for flavoring in foods, beverages, cosmetics, and daily chemical products. Whether in high-end perfumes or mass-market cleaning products, citral brings a distinct sense of freshness and naturalness to products. 2 Irreplaceability as a Key Synthetic Intermediate: The most important strategic value of citral lies in its role as a universal intermediate for the synthesis of downstream high-value chemical products. Through a series of chemical reactions, citral can derive various compounds with extremely high economic value in the flavor and pharmaceutical fields, including ionone (used for synthesizing Vitamin A), damascone (a core component of rose-type flavors), methyl ionone, geraniol, nerol, and citronitrile. Citral is not only a key raw material for the synthesis of Vitamin A but also a precursor for the synthesis of important nutritional chemicals such as Vitamin E and phytol. Its production is difficult and has high technical barriers, earning it the reputation of being the pearl in the crown of fine chemicals, holding a very important strategic position in the entire industry chain. 3 Good Bioactivity – Natural Antimicrobial and Insect Repellent Properties: Scientific research has shown that citral has good antibacterial, antifungal, and insect repellent properties. As a component of natural cleaning products and insect repellents, it has inhibitory effects on various foodborne pathogens such as Staphylococcus aureus, Escherichia coli, and Salmonella, and also has repellent effects against mosquitoes, ticks, and mites. This property gives it broad application prospects in natural preservatives, biopesticides, oral care, and personal care products. 4 Nature-identical and Clean Label Properties: Citral naturally occurs widely in various plant essential oils such as lemongrass oil, litsea cubeba oil, and lemon oil. A large number of commercial products are nature-identical products separated and extracted from natural essential oils. This aligns well with current global consumer preferences for natural, clean label, and plant-based products, giving it higher consumer acceptance and market competitiveness in food flavoring and premium daily chemical products. 5 Compliant and Safe Usage History: Citral has been approved as a permitted food flavor by multiple international authorities including China GB 2760, US FDA 21 CFR 182.60, FEMA, and EU EC 1333/2008. It also holds international religious clean certifications such as KOSHER and HALAL, with a long history of safe use. Its safety assessment is fully established, and it is widely used globally. 6 Stability and Strategic Value of Global Supply: In the past, citral production was highly dependent on two companies, BASF and NHU, with high supply concentration, making prices and supply chains vulnerable to industry fluctuations. In recent years, with the successful commissioning of Wanhua Chemical‘s 48,000 tons/year citral unit, the global citral supply pattern has undergone significant changes, greatly enhancing supply stability and providing more reliable raw material assurance for downstream users.