AN ANTHOCYANIN COMPLEX ISOLATED FROM THE SYRUP OF CANNED BLUEBERRIES

Abstract

SUMMARY ‐The addition of 5 vol ethanol to syrup from canned blueberries caused the precipitation of a blue‐colored anthocyanin complex. The complex, which readily redissolved in water, was decomposed under strongly acid conditions. The complex contained glycosides of the antho‐cyanidins, delphinidin and petunidin. It also contained a high proportion of a polysaccharide resembling pectin and a small proportion of proteinaceous material. Cations detected by X‐ray fluorescence spectroscopy included: aluminum (0.13%), calcium (0.13%), iron (0.12%) and potassium (0.67%). Tin was not detected in the complex. There was some evidence that the complex also contained leucoanthocyanins. The results of ultracentrifugation studies suggested that the molecular weight was between 77,000,000 and 490,000,000.