Citral CAS 5392-40-5

English name	Citral
Chinese name	柠檬醛
CAS	5392-40-5
Molecular formula	C10H16O
Molecular weight	152.23
EINECS	226-394-6
Melting point	<-10°C
Boiling point	229 °C (lit.)
Bulk density
Density
Vapor density	5 (vs air)
Vapor pressure	0.2 mm Hg ( 200 °C)
Storage conditions	2-8°C
Solubility	0.42 grams per liter
Form	Liquid
Color	Colorless to light yellow
Smell type	citrus

Limonene is a pale yellow, oil-like, volatile liquid with a lemon-like fragrance. Its odor is intense and strong, resembling that of lemon. The chemical properties of limonene are relatively active and it is prone to undergo oxidation-reduction reactions, generating farnesol or nerol/orrisone. Under the action of sulfuric acid, it can cyclize to form p-isopropylbenzene. It is unstable in alkaline conditions and can resinify under the action of strong alkali. 

Limonaldehyde is a colorless or slightly yellow liquid with a strong lemon fragrance. It is non-rotatory. The boiling point is 228℃, and the flash point is 92℃. There are two isomers: cis and trans. When treated with sodium bisulfite, the cis form has extremely low solubility, while the trans form has a much higher solubility. Therefore, they can be separated. Cis limonaldehyde: relative density (d20) 0.8898, refractive index (nD20) 1.4891, boiling point 118-119℃ (2666Pa). Trans limonaldehyde: relative density 0.8888, refractive index (nD20) 1.4891, boiling point 117-118℃ (2666Pa). It dissolves in non-volatile oils, volatile oils, propylene glycol and ethanol, but does not dissolve in glycerol and water. It is unstable in alkaline and strong acidic conditions. Natural products are found in lemon grass oil (70%-80%), nutmeg oil (about 70%), lemon oil, white lemon oil, citrus leaf oil, etc. 

Purpose

GB 2760—96 stipulates that these are the permitted edible flavorings. They are mainly used for preparing lemon, citrus and mixed fruit flavor essences, and are also the main raw material for synthesizing violet ketone.

Used as a fragrance additive, for preparing lemon essence, also used as the main raw material for synthesizing violet ketone and vitamin A.

It has a wide range of applications, used in various aspects that require lemon aroma. It is an important flavoring for lemon-type, deodorizing wood-type, artificially prepared lemon oil, fragrant lemon oil and orange leaf oil edible essences. It is also a raw material for synthetic violet ketone series and methyl violet ketone series Chemicalbook. It can also be used to mask unpleasant odors in industrial production. It can also be used in ginger, lemon, white lemon, sweet orange, round tangerine, apple, cherry, grape, strawberry and spicy edible essences. It can also be used in wine essences.

Limonene is an edible flavoring permitted by China for use. It can be used to prepare fruit-type edible essences such as strawberry, apple, apricot, sweet orange, lemon, etc. The dosage is according to normal production needs. Generally, it is 1.70mg/kg in gum candies; 43mg/kg in baked foods; 41mg/kg in candies; 23mg/kg in cold drinks; 9.2mg/kg in soft drinks.

It is used for the preparation of artificial lemon oil, citrus oil, and other citrus-type fragrances, as well as fruit essences, cherry, coffee, plums, etc. for food. It is also widely used as an additive for detergent for tableware, soap, and cologne. Limonene is a raw material for synthesizing violet ketone, methyl violet ketone, dihydro camphor ketone, etc. in the chemical industry. It can also be reduced to citronol, orange alcohol and linalool; or converted into limonocyn. It is used in the pharmaceutical industry to manufacture vitamins A and E, and is also a raw material for phytol.

Synthetic vitamin A. Flavoring.