identified four new compounds by HPLC, mass spectroscopy and nuclear magnetic resonance, derived from the reaction between anthocyanins and hydrocinnamic acid in the juice of blood oranges during storage. They were denominated as Pyranoanthocyanins. It is thus believed that the anthocyanins were polymerized during storage, both in the fruits and juice, and that these compounds derived from condensation, were not identified in the HPLC analyses under the conditions used in the present study
spectrophotometry, and for this reason, the losses appeared to be
more significant