Rubus fruit phenolic research: The good, the bad, and the confusing

Here we attempt to clarify contemporary scientific findings of Rubus fruit phenolics, focusing mainly on published peer-reviewed work from the last 6 years. Our review focuses on research papers that identified phenolics of Rubus fruit, although other edible parts of Rubus plants (i.e. leaves, roots) also contain phenolics. With an increased awareness given to the potential health benefits of consuming berries high in phenolics, efforts have been directed at enhancing Rubus fruit quality and colour (through plant selection, harvesting, storage, etc.) for processors and consumers alike. Assessment of any progress requires knowing the state of the starting material, so effective research into Rubus phenolics relies upon the accurate identification of the components in Rubus fruit in the initial investigations. We have summarised these reports into three sections: anthocyanins, phenolic monomers other than anthocyanins, and phenolic polymers. More work is needed in identification and quantification, and further opportunities remain for deciphering and clarifying existing phenolic information for Rubus fruit.