Alleged Cranberry Adulteration

The Botanical Adulterants Program was alerted by Nutra Canada (Champlain, Quebec, Canada) about the sale of adulterated cranberry (Vaccinium macrocarpon, Ericaceae) extract material. After initial testing using a high-performance liquid chromatography-ultraviolet (HPLC-UV) fingerprinting method by a third-party laboratory indicated that the composition of the material did not correspond to the composition of authentic cranberry extract, the company had extensive ultra-HPLC-UV with diode array and single quadrupole mass spectrometric detection [UHPLC-UV(DAD)/MS(SQD)] testing performed by Botanicert (Grasse, France). The results – when compared to authentic cranberry extract – showed a different proanthocyanidin (PAC) profile, the presence of anthocyanins different from those of cranberry, different hydroxycinnamic acids, and the absence of iridoid glycosides in the raw material. The extract showed type A or type B PACs, with type A being more abundant. According to the literature, there are a few materials, other than cranberry, that can provide type A PACs: blueberry (Vaccinium angustifolium, V. corymbosum, V. pallidum, Ericaceae), bilberry (V. myrtillus), lingonberry (V. vitis-idaea), and other Vaccinium spp., as well as plums (Prunus domestica, Rosaceae), peanut (Arachis hypogaea, Fabaceae), and cinnamon (Cinnamomum verum, Lauraceae). The skin of peanut, which contains more type A than type B PACs, was suggested as the most likely adulterant.

Comment: Based on the recent evidence of the substitution of grape (Vitis vinifera, Vitaceae) seed extracts with extracts made from peanut skin (discussed in the previous issue of this publication), it may not come as a surprise that other PAC-containing extracts are subject to adulteration as well. Peanut skin extract makes a particularly challenging adulterant for cranberry extract since its chemistry is similar to that of cranberry extract. While some cranberry fruit powders with ca. 0.5% PAC contents (measured by the BL-DMAC assay) cost around US $70.00/kg, extracts standardized to 15% PAC according to the BL-DMAC method cost around US $550.00/kg, making adulteration of such extracts a very lucrative business. Adulteration can be detected based on comparison of the HPLC-UV fingerprint of the flavan-3-ol monomers, dimers, and polymers, and by comparison of the anthocyanin profile with the profiles of authentic cranberry extract. In addition to peanut skin extract, cranberry extract has been subject to adulteration with grape seed extract,¹ which has been the topic of discussion in a previous issue of this publication. Beyond economic fraud, non-compliance with Good Manufacturing Practices (GMPs), and producing a potentially ineffective product, the adulteration of cranberry with peanut skins, if confirmed, has implications regarding the non-compliance with allergen labeling regulations. The presence of ingredients made from peanuts must be disclosed on the product label, and failure to do so can have serious health consequences for those who suffer from peanut allergies.

Reference

1.     Navarro M, Núñez O, Saurina J, Hernández-Cassou S, Puignou L. Characterization of fruit products by capillary zone electrophoresis and liquid chromatography using the compositional profiles of polyphenols: application to authentication of natural extracts. J Agric Food Chem. 2014;62(5):1038-1046.

Note: The evidence for the above-reported case of adulteration is based on internal data gathered by the companies but has not been independently verified by a third-party analytical laboratory.