시트랄

Citral occurs as (2Z)- and (2E)-isomers (citral a and b, respectively) analogous to the corresponding alcohols, geraniol and nerol: geranial (citral a), bp2.7 kPa 118–119 °C, d20 0.8888, n20 D 1.4898; neral (citral b), bp2.7 kPa 120 °C, d20 0.8869, n20 D 1.4869. Natural citral is nearly always a mixture of the two isomers. It occurs in lemongrass oil (up to 85%), in Litsea cubeba oil (up to 75%), and in small amounts inmany other essential oils. The citrals are colorless to slightly yellowish liquids, with an odor reminiscent of lemon. Since citral is an α,β-unsaturated aldehyde with an additional double bond, it is highly reactive and may undergo reactions such as cyclization and polymerization. Geraniol, citronellol, and 3,7-dimethyloctan-l-ol can be obtained from citral by stepwise hydrogenation. Citral can be converted into a number of addition compounds; the (Z)- and (E)-isomers can be separated via the hydrogen sulfite addition compounds.The condensation of citral with active methylene groups is used on an industrial scale in the synthesis of pseudoionones, which are starting materials for ionones and vitamins.

출처Reported found in apricot, clary sage, ginger, grape, grapefruit, lemon, lime, mandarin, orange, raspberry, tamarind, tangerine, tea and tomato.

용도Citral is an anti-microbial agent found in plants with antibacterial activity against some food pathogens. It is also a fragrance compound with a distinct lemon scent.

일반 설명A clear yellow colored liquid with a lemon-like odor. Less dense than water and insoluble in water. Toxic by ingestion. Used to make other chemicals.

순도시험(1) 비중 : 이 품목의 비중은 0.885～0.891이어야 한다. (2) 굴절률 : 이 품목의 굴절률 은 1.486～1.490이어야 한다. (3) 용상 : 이 품목 1mL를 60% 에탄올 10mL에 녹일 때, 그 액은 징명하여야 한다. (4) 산가 : 이 품목의 산가는 향료시험법 중 산가측정법에 따라 시험할 때, 5 이하이어야 한다.

확인시험이 품목 1mL에 아황산수소나트륨시액 2mL 및 탄산나트륨시액 2방울을 가하여 흔들어 섞으면 발열하여 백색의 결정덩어리로 된다. 이에 아황산수소나트륨시액 10mL를 추가하여 수욕중에서 흔들어 섞으면서 가열하면 이 결정덩어리는 녹으며 레몬과 같은 향기는 없어진다.

정량법이 품목 약 1g을 정밀히 달아 향료시험법 중 알데히드류 및 케톤류함량측정법의 히드록실아민법 제2법에 따라 정량한다. 다만 방치시간은 15분간으로 한다.0.5N 염산 1mL ＝ 76.12mg C10H16O

정의Commercial material is a mixture of α and β isomers.