While high-hydrostatic pressure (HHP) has successfully been applied to the pasteurization of fruit and vegetable juice beverages, their quality-stable shelf life during storage has not been fully elucidated. Therefore, we investigated the effect of HHP (550 MPa/10 min) treatment on polyphenols, carotenoids, ascorbic acids, and antioxidant capacity in tomato juice and their changes during 4-week refrigerated storage. High-temperature short-time (HTST, 110 °C/8.6 s) treatment was used as a control. The results revealed a significantly greater presence of polyphenols, carotenoids, ascorbic acid content, and antioxidant capacity in tomato juice after HHP processing than after HTST processing. However, the total carotenoids and total phenolic content in HHP-treated tomato juice decreased dramatically and approached that in the HTST-treated tomato juice after 1 week of storage. Therefore, HHP’s advantage in maintaining antioxidant compounds and capacity was only evident during the first week of storage in tomato juice. Nevertheless, the post-storage caffeic acid, quercetin, ferulic acid, and p-coumaric acid concentrations were 8.31, 4.77, 1.86, and 6.84 μg/g higher in the HHP-treated than in HTST-treated tomato juice, respectively. This study provides a new perspective for predicting HHP products' quality-stable shelf life.

High hydrostatic pressure has become a non-thermal alternative to thermal pasteurization in dairy product processing. In this study, we investigated the effects of the treatment of high hydrostatic pressure on the bacterial composition in donkey milk using high-throughput sequencing technology and culture-dependent methods. Compared with the microbial composition in the untreated donkey milk, the relative percentage of Pseudomonas and Acinetobacter in donkey milk after high hydrostatic pressure was significantly decreased by 4.92% and 4.82%, respectively. Beta diversity analysis demonstrated that the treatment of high hydrostatic pressure affected the microbial composition in donkey milk significantly. The potential probiotic Enterococcus casseliflavus isolated from the untreated donkey milk has a good acidifying ability. This study revealed the effects of high hydrostatic pressure treatment on the microbial composition in donkey milk, exhibiting its practical industrial application and the potential use of biological resources in the future.