The aim of this study was to use nanocomposites of polypropylene (PP) and montmorillonite (MMT), prepared by melt intercalation in a twin-screw extruder, as a food packaging material. The nanocomposites were evaluated by thermal, mechanical, and morphological analyses. Measurements of oxygen and water vapor permeability were also conducted to the nanocomposites. Besides, orange juice was used as modeling food and its physical-chemical and microbiological properties were determined. Despite of no significant changes in tensile properties were observed to the nanocomposites, the impact strength presented a substantial enhancement and the rigidity as well. Besides, MMT have shown a high capacity to improve oxygen barrier properties of PP. Electronic microscopy revealed certain homogeneity, showing some MMT-exfoliated lamellae in the PP matrix. Regarding the package efficacy, the orange juice quality was maintained after 10 days of storage. Concluding, this study seems to clarify a little more the claimed efficiency of nanocomposites as food packing materials.