Location: Mycotoxin Prevention and Applied Microbiology Research
Title: Detection of carob flour in cocoa powder by direct analysis in real time-mass spectrometry (DART-MS)Author
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Maragos, Chris |
Submitted to: Food Additives & Contaminants. Part A: Chemistry, Analysis, Control, Exposure & Risk Assessment
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/10/2025 Publication Date: 1/21/2025 Citation: Maragos, C.M. 2025. Detection of carob flour in cocoa powder by direct analysis in real time-mass spectrometry (DART-MS). Food Additives & Contaminants. Part A: Chemistry, Analysis, Control, Exposure & Risk Assessment. https://doi.org/10.1080/19440049.2025.2453496. DOI: https://doi.org/10.1080/19440049.2025.2453496 Interpretive Summary: The value of cocoa has increased substantially recently, a result of declining production due to pests, diseases, climate, and the availability of labor. The high value of cocoa products makes them a target for adulteration with less expensive ingredients such as carob flour. Rapid methods to detect adulteration of cocoa powder are needed to protect consumers from fraudulently labeled products. Researchers with the USDA-ARS in Peoria, Illinois, developed a rapid method for detecting cocoa powder adulterated with 15% carob flour. The method relied upon distinguishing 'fingerprints' of pure cocoa powder from that containing carob. The method was 96% accurate and will provide importers of cocoa with a tool to rapidly detect adulteration. Technical Abstract: Cocoa is a high value product and therefore a potential target for economic adulteration with less expensive ingredients. Carob flour is less expensive than cocoa powder and is frequently cited as a potential cocoa substitute. While carob has legitimate uses as a cocoa replacement, these characteristics also make it a potential adulterant of cocoa powder. Direct analysis in real time mass spectrometry (DART-MS) is an ambient ionization MS technique that can be used to rapidly interrogate samples. Samples of cocoa powders, carob flours, and mixtures of the two were extracted with buffer and interrogated by DART-MS. The mass spectra were used to develop models to distinguish between cocoa powder and cocoa powder amended with carob. A principal component-linear discriminant analysis (PCA-LDA) model was used to discriminate between cocoa powder and cocoa powder amended with 15% carob flour. The accuracy using internal validation was 100%. Using an external validation dataset, the accuracy, precision, and recall were 96.0%, 94.8%, and 97.3% respectively. These results suggest that DART-MS can be used to discriminate between cocoa powder and cocoa powder adulterated with 15% carob. |