Combined effect of microwave and ultrasonication treatments on the quality and stability of sugarcane juice during cold storage

Abstract

Summary The main objective of this study was to investigate the combined effect of microwave ( MW ) treatment (2450 MH z for 120 s), ultrasonication ( US ) (24 KH z, 20 °C for 20 min) and combined treatment ( MW ‐ US ) on the quality and stability of sugarcane juice ( SCJ ) during 21 days of storage at 4 °C. The effect of the treatments and storage time on physicochemical, bioactive compounds (total phenolic, flavonoids and ascorbic acid content) and microbial analysis of SCJ . No significant ( P < 0.05) changes were observed in °Brix, while there was an increase in pH and a decrease in titratable acidity in all treatments. Compared to US and MW , MW ‐ US treatments was more effective in preserving colour attributes, total phenolic and flavonoids contents, ascorbic acid and antioxidant capacities of the SCJ during storage. The results regarding the microbial count indicate that more microbial safety and longer shelf life was achieved by MW ‐ US . MW ‐ US treatment is an effective technology for improving the safety and shelf life of SCJ by minimising quality changes, retaining bioactive compounds and reducing microbial growth during storage.