Storage Stability of Selected Vegetable Purees in High Barrier Pouches Processed With Pressure-Assisted Thermal Sterilization

Abstract

This study evaluated the stability of physicochemical properties, including the enzymatic activity of polyphenol oxidase (PPO) and the concentration of natural pigments, of three vegetable purees packaged in high barrier pouches after pressure-assisted thermal sterilization (PATS) and 6 months storage. The red beetroot, red cabbage, and carrot purees sealed in a high-barrier polymeric pouch were subjected to a PATS treatment at an operating pressure of 600 MPa and a starting vessel temperature of 90°C for a 5 min process. After PATS, the residual activities of PPO ranged from non-detectable to 8.1%. A total color difference (ΔE) in different purees varied between 4.23 and 5.53. The PATS treatment caused significant degradation in the content of betalains in the beet puree, while both anthocyanins in the cabbage puree and beta-carotene in the carrot puree exhibited a higher retention. During the 6 months of storage, cabbage puree showed a higher ΔE value and PPO residual activities than beetroot and carrot purees. Both anthocyanins and betalains experienced significant degradation, but beta-carotene had a high storage stability.