Evaluation of quality changes of pressurized and pasteurized herbal-plant beverages during chilled storage

Abstract

© 2008 IFRJ, Faculty of Food Science & Technology, UPM. The physicochemical and microbiological qualities of pressurized herbal-plant beverage at 400 MPa and 25°C for 30 min and pasteurized beverage at 90°C for 2 min were investigated during storage at 4°C for 4 weeks. It was found that the brightness (L) of both processed beverages noticeably decreased (P < 0.05) with an increasing storage time, while other parameters such as a*(reddish), b*(yellowish), ΔE (total different colors) and BI (Browning Index) were trended to increase. In addition, the bioactive components, i.e. ascorbic acid, γ-oryzanol, asiatic acid, gallic acid, ellagic acid and total phenols, and antioxidant capacity (DPPH assay) in both processed beverages significantly declined (P < 0.05) throughout the entire storage. Overall the results displayed that pressurization could maintain the natural color and bioactive compounds of the product better than thermally process.