Effect of ultrasound followed by high pressure processing on prebiotic cranberry juice

- Prebiotic cranberry juice was submitted to non-thermal processing.
- Seven anthocyanins were identified by UPLC-qTOF-MS.
- The FOS preservation was good despite a slight depolymerization.
- The juice color and pH were well preserved.
- An increase in anthocyanin content (up to 24%) was observed.

This work evaluated the effect of high pressure processing (HPP) and ultrasound (US) on the quality of prebiotic cranberry juice fortified with fructo-oligosaccharides (FOS). The juice was subjected to HPP for 5 min (450 MPa) and to ultrasonic treatment for 5 min (600 and 1200 W/L) followed by HPP for 5 min (450 MPa). Chemical analyses were carried out to identify and quantify the anthocyanins, and to quantify FOS, organic acids, instrumental color, soluble solids, pH and antioxidant capacity. Both non-thermal treatments preserved the FOS content maintaining the prebiotic property of the juice. The retention of organic acids was high (>90%) and an increase in anthocyanin content (up to 24%) was observed when ultrasound was followed by HPP. The changes in instrumental color, soluble solids content and pH were negligible. The use of HPP and ultrasound processing has been proven satisfactory to treat prebiotic cranberry juice.