Identification of Ellagic Acid in Blackberry Juice Sediment

The sediment in a commercial reconstituted 'Evergreen' blackberry (Rubus laciniatus L.) juice concentrate was found to be composed of ellagic acid, protein, and other unidentified compounds. The qualitative tannin and protein-tannin haze test indicated that the sediment was predominantly tannin or protein-tannin complexes. Nitrogen determination showed the sediment to be 6.69% +/- 2.21% protein on a dry-weight basis. Almost all of the extractable material was identified as ellagic acid by high-performance liquid chromatography and liquid chromatography-mass spectrometry. The ellagic acid content of the wet sediment was 0.05 g/100 g, whereas it was 7.41 g/100 g in freeze-dried sediment. Tannase enzyme did not significantly decrease the concentration of ellagitannins in Marion blackberry (Rubus spp. Hyb.) juice in this study.