Authentication of fresh apple juice by stable isotope ratios of δD, δ18O and δ13C

Abstract

Abstract The authentication of fresh apple juice (FAJ) is a significant issue. However, the main characteristics of FAJ, diluted apple juice (DAJ) with added concentrated apple juice (DAJ+CAJ), and DAJ with added sucrose (DAJ+s) are not different when using classical chemical analyses in juice authentication. In this study, isotope ratio mass spectrometry (IRMS) was used to determine the δD, δ18O, and δ13C in adulterated apple juice for juice authentication. The δD and δ18O values were decreased in adulterated juice. A linear correlation was found between δD and δ18O in apple juices with different amount of adulteration. Therefore, this linear relationship can be used to determine the amount of adulteration that took place. The δ13C value and the content of each component in real apple juice are within specific ranges. The adulteration can be recognized once the δ13C value and the content of each component in the apple juice are out of these ranges. The implementation of this method would help maintain the juice market’s stability and protect consumers’ interests.