Effect of high pressure processing and trehalose addition on functional properties of mandarin juice enriched with probiotic microorganisms

- L. salivarius has shown a positive effect against all food pathogens tested.
- Homogenization at 20 MPa allows obtaining high quantities of microorganism.
- Trehalose and homogenization influence stability of probiotic during storage.
- In an optimum media homogenization pressures improves probiotic hydrophobicity.
- In stress conditions trehalose interactions improve probiotic hydrophobicity.

This work aimed to determine the effect of homogenization pressures and addition of trehalose on the functional properties of mandarin juice enriched with Lactobacillus salivarius spp. salivarius. Physicochemical and structural properties of mandarin juice were evaluated and related with quantity and stability of probiotic microorganism as well as with its hydrophobicity. Both food matrix and processing, affected functional properties of L. salivarius spp. salivarius. Homogenization pressures and trehalose addition affected quantity and stability of probiotic microorganisms during storage. 20 MPa and 20 MPa with 100 g/kg of trehalose allowed obtaining 106 colony forming units (CFU)/ml mandarin juice after ten storage days. In MRS growth, cell hydrophobicity increased with homogenization pressures, with values in range 67-98%. Highest cell hydrophobicity was obtained in samples homogenized at 100 MPa. Under stress growth conditions, cell hydrophobicity values were in a range 30-84%. In samples no homogenized, addition of trehalose resulted in an increased values of hydrophobicity, with highest levels in those samples with 100 g/kg of trehalose addition.