The present research examined the stabilization of Listeria phage A511 in whey protein concentrate (WPC), pullulan (PULL) films and their composites. The functional properties of the films were investigated during 60 days of storage at 25 ◦C and relative humidity of 53%. Pure films of WPC and PULL were not successful in phage stabilization. The highest phage recovery at zero time belonged to 30WPC:70PULL and 50WPC:50PULL films. Phage distribution was uniform in composite films. Addition of phage to the films resulted in enhanced opacity, b and ΔE. Antimicrobial effects in the solid medium in 50WPC:50PULL and 70WPC:30PULL films were reduced to zero, and the opacity, b and ΔE of phage-containing films increased over 60 days. In 30WPC:70PULL film the elastic modulus and tensile strength were enhanced while the elongation at break was reduced over time. Overall, 30WPC: 70PULL film had the best performance of the physical, mechanical and anti-Listerial properties during storage.

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