If students are new to chromatography, it is important to point out that a perfect separation is not the object of the experiment but to explore the information that can be obtained from the paper chromatography. The formic acid mixture offers a cleaner separation because of its increased polarity. Smearing is not due to inadequate separation but to the large number of components. For each anthocyanidin there are typically 2-7 different anthocyanins present in any food sample. These differ by the identity and attachment point of the glycosides to the anthocyanidin backbone. This leads to inevitable smearing of paper chromatography results for the anthocyanin samples prior to hydrolysis. Anthocyanidins yield cleaner results, but there are several closely related anthocyanidins in each of the hydrolyzed samples, particularly blueberry, which lead to closely spaced spots in the hydrolyzed samples.2 Rf values are tabulated in the literature.1,3