Phenolic Compounds Stability of Grumixama (Eugenia brasiliensis) Juice during Processing and Storage

Grumixama is an anthocyanin-rich berry commonly found in South America, yet not widely consumed by Brazilians due to the lack of studies covering its technological properties. Therefore, the stability of anthocyanins and the activity of oxidoreductase enzymes in grumixama juice during thermal treatment (60 °C to 100 °C) and storage (at 25 °C and 7 °C) were evaluated. As a result, the pasteurization of grumixama juice at 80 °C for 60 s completely inactivated peroxidase (POD) and polyphenol oxidase (PPO), eliminated microorganisms, and induced low degradation of the total anthocyanins (40%) and minimal degradation of the total phenolic compounds. Four anthocyanins were monitored in the pasteurized juice, namely delphinidin 3-glucoside, cyanidin 3-glucoside, and two unidentified anthocyanins. Despite the temperature range, the qualitative chromatographic profile of the anthocyanins did not change, while the contents were affected. The binominal temperature/time of 80 °C/60 s effectively inactivated PPO and POD enzymes, promoted moderate alterations in the contents of total anthocyanins and total phenolic compounds, and ensured the microbiological quality of grumixama juice. Grumixama juice can be used as a health food due to its high content of antioxidant phenolic compounds, especially anthocyanins.