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Sampling and Pretreatment of Tooth Enamel Carbonate for Stable Carbon and Oxygen Isotope Analysis
Published on: August 15, 2018
Carbon stable isotopic compositions of citric acid and malic acid in Japanese apricot liqueur decrease as the fruit
Fumikazu Akamatsu1, Yasuhisa Tsuchida2, Takaaki Oe2
1National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan.
Abstract:
The carbon stable isotopic composition (δ13C) is often analyzed to quantify the addition of acidulants to Japanese apricot liqueur, but little is known about the variation in the δ13C values of the main organic acids arising from differences in the ripeness of Japanese apricots. We show that in Japanese apricot liqueur prepared using fruits at different stages of ripeness, the δ13C values of citric acid and malic acid ranged from -25.1‰ to -23.7‰ and from -22.3‰ to -19.7‰, respectively, and the δ13C values decreased as the fruit ripened. The average δ13C value of citric acid from liqueurs was 0.7‰ higher than that from fresh fruits, whereas the δ13C values of malic acid showed no isotope discrimination. The variation in δ13C values of the main organic acids in Japanese apricot liqueurs will help detect acidulant addition and control authenticity.
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