Due to the high cost of the cranberry extract, there have been several reported cases of adulteration. The aim of our study was to find markers to authenticate extracts or cranberry-based food supplements. Cranberry fruits from 7 countries, 17 cranberry extracts and 10 cranberry-based food supplements were analysed by UPLC-DAD-Orbitrap MS. Procyanidins were assessed by DMAC method. Anthocyanin fingerprint and epicatechin/catechin, procyanidin A2/total procyanidin and procyanidin/anthocyanin ratios were used as markers, and PCA carried out to check for similarity. Approximately 24% and 60% of the extracts and food supplements, respectively, differed significantly from the fruits. One seemed adulterated with Morus nigra and two with Hibiscus extract. Six food supplements were non-compliant and five contained mainly cyanidin-glucoside and cyanidin-rutinoside, suggesting adulteration with M. nigra extract. Only four products contained the procyanidin amount declared on the package, and only one provided the daily dose deemed effective for treating a urinary tract infection.

Consumers must be assured that bought food supplements contain both bilberry extract and the anthocyanin amounts that match the declared levels. erefore, a Fourier transform near-infrared (FT-NIR) spectroscopic method was validated based on principal component scores for the prediction of bilberry extract adulteration and partial least squares regression model for total anthocyanin evaluation. Anthocyanins have been quantified individually in 71 commercial bilberry extracts by HPLC-DAD, and 6 of them were counterfeit. e anthocyanin content in bilberry extracts was in the range 18-34%. Authentic bilberry extracts (n � 65) were divided into two parts: one for calibration (n � 38) and the other for the validation set (n � 27). Spectra were recorded in the range of 4000-12500 cm 1 , and a good prediction model was obtained in the range of 9400-6096 and 5456-4248 cm 1 with r 2 of 99.5% and a root-mean-square error of 0.3%. e adulterated extracts subjected to NIR analysis were recognized as noncompliant, thus confirming the results obtained by chromatography.e FT-NIR spectroscopy is an economic, powerful, and fast methodology for the detection of adulteration and quantification of the total anthocyanin in bilberry extracts; above all, it is a rapid, low cost, and nondestructive technique for routine analysis.

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