Effects of high-pressure processing and thermal pasteurization on quality and microbiological safety of jabuticaba (Myrciaria cauliflora) juice during cold storage.

Abstract

The aims of this study were to investigate the effects of high-pressure processing (HPP) on jabuticaba juice characteristics including microbial levels, phenolic compounds, antioxidant activity, and physicochemical properties during 28days of storage at 4°C and to perform a sensory evaluation. Juice samples were pressurized at 200, 400, or 600MPa for 5min. During thermal processing, juice was treated in a water bath at 90°C for 60s. Elevated aerobic plate counts, coliforms, psychrotrophs and yeasts/molds, were not detected in the HPP-400, HPP-600, or thermal-processed (TP) juices and further cold storage showed at least a shelf life of 28days at 7°C. All HPP-treated juice had significantly higher antioxidant capacities, higher total phenolic, flavonoid, and monomeric anthocyanin content, and lower browning degrees, compared with the TP. The soluble solid content, titratable acidity and pH were not significantly different in the HPP-400, HPP-600, and TP after 28days. The ΔE values were significantly increased in all juice samples. Sensory analysis indicated that the HPP-treated juices had higher acceptance and lower bitter perception. In conclusion, HPP treatments above 400MPa were effective in ensuring microbiological safety, maintaining the overall quality parameters, extending the shelf life, and achieving consumer acceptance.