Development of a mixed jussara and mango juice with added Lactobacillus rhamnosus GG submitted to sub-lethal acid and baric stresses.

Abstract

This study evaluated the interference of sub-lethal acid (SLA) stress and high isostatic pressure (HIP) stress on the survival of Lactobacillus rhamnosus GG (LGG) in mixed jussara and mango juice with the pH adjusted to 3.0 and 3.5, during 90days of storage at 6°C. The SLA stress at pH 4.0 previously applied to the LGG cells had no effect on the survival of this bacterium in mixed jussara and mango juices. On the other hand, the application of 200MPa/5min/25°C treatment to LGG cells was shown to be efficient in the cross protection of this bacterium in an acid medium. Pressures above 400MPa/5min/25°C caused a reduction in the viability in an acid medium and lower pressures (< 100MPa) showed similar results compared to control treatment in the LGG survival. No changes in pH, acidity and soluble solids were observed in mixed juices. In addition, these products showed elevated levels of anthocyanins, phenolic compounds and antioxidant capacity. This highlights the capacity of the HIP process to promote the cross protection of LGG in an acid medium.