Release of nisin from polyvinyldichloride lacquer coated on a polyethylene film

Polyethylene films coated with commercially available polyvinyldichloride (PVdC) lacquer with the addition of nisin preparation Nisaplin (5.0% to 33.4%, w/w), i.e. with nisin concentration from 16 500 IU per dm sup(-2) to 110 200 IU per dm sup(-2), were studied at 25 deg C to determine the bacteriocin migration into physiological saline solution. The maximal level of released nisin from films was 5 000 IU per dm sup(-2), which was less than 10% of the total theoretical amount of nisin added to the coating. Equilibrated nisin migration depended on coating thickness. A non-linear relation between the equilibrium nisin migration level and the coating thickness of the nisin preparation was found. A diffusion coefficient of 2.37 × 10 sup(-10) cm sup(2) per s sup(-1) plus minus 0.82 × 10 sup (-10) per cm sup(2) per s was determined on the basis of migration data.