Shelf life of HHP-processed peach puree with antibrowning agents

Natural peach puree and peach puree containing 500 ppm of ascorbic acid (AA) or cysteine (250 ppm) were treated at high pressure (517 MPa/5 min). High hydrostatic processing (HHP)-processed and control purees were stored at 3, 21 and 35 +/- 1 C for 30 days. Total count, yeast/molds, color and polyphenoloxidase (PPO) activity were analyzed regularly. PPO activity was reduced to 12.1, 26.4 and 5.5% in both the natural puree and puree containing AA and cysteine after applying HHP PPO activity of the non-HHP-processed puree containing cysteine was different from the other purees, as well as the PPO activity of HHP-processed purees. Non-HHP-processed natural puree (yellow color) and purees containing AA (yellow color) and cysteine (orange color) maintained their colors individually for 9 days. HHP-processed purees maintained their yellow (natural puree and puree with AA) and orange colors (puree containing cysteine) for 21 to 24 and 30 days, respectively. Less than 10 cfu/g were counted in HHP-processed purees stored at 3C.