Detection of Additives and Chemical Contaminants in Turmeric Powder Using FT-IR Spectroscopy
AbstractYellow turmeric (Curcuma longa) is widely used for culinary and medicinal purposes, and as a dietary supplement. Due to the commercial popularity of C. longa, economic adulteration and contamination with botanical additives and chemical substances has increased. This study used FT-IR spectroscopy for identifying and estimating white turmeric (Curcuma zedoaria), and Sudan Red G dye mixed with yellow turmeric powder. Fifty replicates of yellow turmeric—Sudan Red mixed samples (1%, 5%, 10%, 15%, 20%, 25% Sudan Red, w/w) and fifty replicates of yellow turmeric—white turmeric mixed samples (10%, 20%, 30%, 40%, 50% white turmeric, w/w) were prepared. The IR spectra of the pure compounds and mixtures were analyzed. The 748 cm−1 Sudan Red peak and the 1078 cm−1 white turmeric peak were used as spectral fingerprints. A partial least square regression (PLSR) model was developed for each mixture type to estimate adulteration concentrations. The coefficient of determination (R2v) for the Sudan Red mixture model was 0.97 with a root mean square error of prediction (RMSEP) equal to 1.3%. R2v and RMSEP for the white turmeric model were 0.95 and 3.0%, respectively. Our results indicate that the method developed in this study can be used to identify and quantify yellow turmeric powder adulteration. View Full-Text
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Dhakal, S.; Schmidt, W.F.; Kim, M.; Tang, X.; Peng, Y.; Chao, K. Detection of Additives and Chemical Contaminants in Turmeric Powder Using FT-IR Spectroscopy. Foods 2019, 8, 143.
Dhakal S, Schmidt WF, Kim M, Tang X, Peng Y, Chao K. Detection of Additives and Chemical Contaminants in Turmeric Powder Using FT-IR Spectroscopy. Foods. 2019; 8(5):143.Chicago/Turabian Style
Dhakal, Sagar; Schmidt, Walter F.; Kim, Moon; Tang, Xiuying; Peng, Yankun; Chao, Kuanglin. 2019. "Detection of Additives and Chemical Contaminants in Turmeric Powder Using FT-IR Spectroscopy." Foods 8, no. 5: 143.
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