Ultra-high pressure homogenization (UHPH) at 300 MPa and 4 C inlet temperature were used to preserve
apple juice, and shelf-life evaluation of aseptically packaged juice was investigated. After processing
Tetra Brik containers were stored at temperatures of 4, 10, 20 and 30 C during 60 days. In this article,
the effect of processing on the spoilage inactivation was evaluated after processing and during the storage
trial. Non-germinated and germinated spores were found in the UHPH-treated juice, being an inactive
population during storage. Patulin content was also not modified by UHPH processing, but a significant
decrease was observed during storage at 30 C (P < 0.05). Polyphenoloxidase (PPO) and pectinmethylesterase
(PME) activity was not found after UHPH-processing and during storage.
A kinetic study of post-processing quality loss was conducted. Vitamin C, chlorogenic acid, total polyphenols
and color change were measured during storage study and were used to model the UHPH-treated
apple juice shelf-life. Loss of vitamin C was correlated with the hydroxymethylfurfural (HMF) accumulation
(0.59, P < 0.05). A limiting quality parameter was polyphenolic content. UHPH-treated apple juice
stored at 4 C was found to show a shelf-life for about 21 months by preserving the color characteristics
of the juice with low HMF accumulation. From 15 C changes in quality parameters were more evident.