Stability of anthocyanins and ascorbic acid of high pressure processed blood orange juice during storage

The stability of anthocyanins (Cy3Gl) and ascorbic acid (AA) of high pressure processed blood orange juice during storage was investigated. Blood orange juice was processed at pressure levels of 400, 500,600 MPa for a constant treatment time of 15 min. During processing >99% and 94.5% retention of Cy3Gl and AA content was observed for all pressure treated samples. The degradation kinetics of processed samples followed first order kinetics during storage. Cy3Gl and AA losses were significantly higher at a storage temperature of 20 degrees C compared to 4 degrees C for both high pressure processed and untreated control samples. During storage at 4 degrees C for 10 days, retention rates for Cy3Gl and AA of 93.4 and 85.0% were observed at 600 MPa and treatment time of 15 min. A strong correlation was observed between AA content and Cy3Gl content with r = 0.79 and r = 0.90 (p < 0.0001) during storage at 4 and 20 degrees C respectively, indicating a strong influence of AA content on Cy3Gl stability during storage. Predicted shelf-life, based upon nutritional requirements, during storage at 20 degrees C of high pressure processed juice samples were found to be higher compared to control samples. Industrial relevance: This study shows the potential benefits of high pressure processing in retaining ascorbic acid and anthocyanins in blood orange juice. High pressure processed samples showed improved shelf life compared to fresh juice. Results presented in this study revealed that high pressure processing helps preserve the nutritional value of blood orange juice during storage. (C) 2011 Elsevier Ltd. All rights reserved.