Application of carbon and hydrogen stable isotope analyses to detect exogenous citric acid in Japanese apricot liqueur.
Japanese apricot liqueur manufacturers are required to control the quality and authenticity of their liqueur products. Citric acid made from corn is the main acidulant used in commercial liqueurs. In this study, we conducted spiking experiments and carbon and hydrogen stable isotope analyses to detect exogenous citric acid used as an acidulant in Japanese apricot liqueurs. Our results showed that the δ13C values detected exogenous citric acid originating from C4plants but not from C3plants. The δ2H values of citric acid decreased as the amount of citric acid added increased, whether the citric acid originated from C3or C4plants. Commercial liqueurs with declared added acidulant provided higher δ13C values and lower δ2H values than did authentic liqueurs and commercial liqueurs with no declared added acidulant. Carbon and hydrogen stable isotope analyses are suitable as routine methods for detecting exogenous citric acid in Japanese apricot liqueur.
National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan. Electronic address: akamatsu99@gmail.com.
Fumikazu
F
Akamatsu
Agriculture, Forestry and Fisheries Depertment, Wakayama Prefecture, 1-1 Komatsubara-dori, Wakayama, Wakayama 640-8585, Japan.
Takaaki
T
Oe
National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan.
Tomokazu
T
Hashiguchi
National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan.
Yuri
Y
Hisatsune
Agriculture, Forestry and Fisheries Depertment, Wakayama Prefecture, 1-1 Komatsubara-dori, Wakayama, Wakayama 640-8585, Japan.
Takafumi
T
Kawao
National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan.
Tsutomu
T
Fujii
D000434:Alcoholic Beverages / Q000032:analysis; D044466:Asian People; D002247:Carbon Isotopes / Q000032:analysis / Q000737:chemistry*; D019343:Citric Acid / Q000737:chemistry*; D006801:Humans; D007554:Isotopes / Q000737:chemistry*; D000068219:Prunus armeniaca / Q000737:chemistry*
D002247:Carbon Isotopes; D007554:Isotopes; D019343:Citric Acid
Acidulant; Authenticity; Carbon stable isotope; Fruit liqueur; Hydrogen stable isotope