Berries are commonly consumed as juice, and juice-processing conditions could affect their bioactive
compounds. This study evaluated the effect of thermal treatments on the antioxidant capacity of
blackberry juice polyphenols. Pasteurized blackberry juices were prepared at 75 8C for 15 s (JP75) and
92 8C for 10 s (JP92). Polyphenol analysis showed that for JP75 and JP92, anthocyanin concentrations
decreased significantly, compared to non-pasteurized juice (NPJ), whereas ellagitannins were not
significantly affected. The evaluation of the DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging capacity
showed a significant decrease of 26% for JP75 and 27% for JP92, and, for the NO (nitric oxygen) scavenging
capacity, the activity was reduced 15% for JP75 and 16% for JP92. There were no significant reductions
observed for the peroxidation inhibitory capacity of the pasteurized juices for any of the oxidation
substrates tested: liposomes, liver homogenates and erythrocytes. Furthermore, the intracellular
antioxidant capacity showed no significant differences due to thermal treatments. The concentration of
phenols necessary to scavenge 50% of the radical oxygen species was 204 9 mg/mL for NPJ, 219 10 mg/
mL for JP75 and 220 9 mg/mL for JP92. This study revealed that pasteurized blackberry juices maintained
their biological properties related to inhibition of peroxidation and their capacity to scavenge intracellular
radicals.