Inhibition of Penicillium commune by edible whey protein films incorporating lactoferrin, lactoferrin hydrolysate, and lactoperoxidase systems

Effects of lactoferrin (LF), lactoferrin hydrolysate (LFH), and lactoperoxidase systems (LPOS), both directly and incorporated into edible whey protein isolate (WPI) films, on the inhibition of Penicillium commune were studied. Mechanical, oxygen-barrier, and color properties of WPI films with and without LPOS were also compared. Antimicrobial effects were examined by turbidity, disc diameter, surface spreading, and film surface inoculation tests. Film elastic modulus, tensile strength, percent elongation, oxygen permeability, and Hunter L, a, and b values were tested. LF and LFH at 10 mg/mL or higher inhibited P. commune in 1% peptone water but not in potato dextrose broth. WPI films incorporating LPOS inhibited growth of P. commune. The properties of WPI films were not significantly changed by incorporation of LPOS (P > 0.05).