Determination of low levels of methanol and ethanol in licorice extract by large volume injection head-space GC.
A large volume injection head-space GC method was established for measuring low levels of residual methanol and ethanol in licorice extract used a food additive. A vial was kept at 50 degrees C in the oven of the head-space sampler. Injection of the head-space gas for 0.75 min into a Poraplot Q GC column with a initial oven temperature of 35 degrees C, enabled the determination of low levels (5 micrograms/g) of methanol and ethanol. The standard deviations for five rounds of analysis of methanol and ethanol in licorice extracts were between 0.82 and 2.97. Methanol was found in 6 samples out of 9 collected in 1999, at concentrations exceeding 50 micrograms/g, the limit set by the Japanese Government, established in 1999 and coming into force on April 1, 2000. The highest concentration reached 10,000 micrograms/g. Methanol at a concentration exceeding 50 micrograms/g was found in 2 out of 9 samples collected in 2000. The highest concentration was 270 micrograms/g.
Uematsu
Yoko
Y
Tokyo Metropolitan Research Laboratory of Public Health: 3-24-1, Hyakunin-cho, Shinjuku-ku, Tokyo 169-0073, Japan.
Suzuki
Kumi
K
Iida
Kenji
K
Hirata
Keiko
K
Ueta
Tadahiko
T
Kamata
Kunihiro
K
D002849:Chromatography, Gas / Q000379:methods*; D000431:Ethanol / Q000032:analysis*; D005503:Food Additives / Q000737:chemistry*; D006035:Glycyrrhiza / Q000737:chemistry*; D000432:Methanol / Q000032:analysis*
D005503:Food Additives; D000431:Ethanol; D000432:Methanol