Release of Propyl Paraben From a Polymer Coating Into Water and Food Simulating Solvents for Antimicrobial Packaging Applications

Abstract

The release phenomena ofpropyl paraben fiom a polymer coating to water and three food simulating solvents (1 0% aqueous ethanol, 50% aqueous ethanol, nheptane) were studied for antimicrobial packaging applications. The effects of food simulating solvent, initial concentration in the coating and temperature on the propyl paraben release were examined. The initial concentration of propyl paraben in the coating rangedfiom 1.26 x lV to 10.52 x 10 g/m' and the temperaturefiom 5.5 to 30C. For water, the release was controlled by Fickian dirusion with constant difision coefficient (7-11 x I@" cmz/s at 30C), and independent of the initial concentration. For 10% ethanol, the release followed again the Fickian model with constant dimion coefficient (30-40 x I @ ] I cmz/s at 30C). For 50% ethanol and n-heptane, the release was instantaneous and not controlled by Fickian dimion. For the release into water, the activation energy for d i f i i o n from the Arrhenius relationship was around 88 kl/mole.

Properties of nisin‐incorporated polymer coatings as antimicrobial packaging materials

“…6,7,9,10 Nisin release from these coatings was only slightly affected by temperature when compared to most cases of additive migration in polymer. Equilibrated migration level of nisin into water increased with temperature up to 20°C but decreased at 40°C ( Figure 2B).…”

“…Electrostatic interaction among the binder, the migrant and the solvent has been known to determine the equilibrated partition of the migrant between the binder and the solvent. 9,14 Nisin has a molecular structure consisting of hydrophilic and hydrophobic components. 13 Lakamaraju et al 26 reported that a hydrophilic surface adsorbed a higher amount of nisin than a hydrophobic one.…”

“…15 The release rate and the extent of migration of the active antimicrobial substance from the packaging materials to the food substrate are the main factors for a given level of antimicrobial activity and speci®city, 16 and have been the topic of many researchers. 6,7,9,10 In the case of nisin-incorporated packaging materials, it is also important to understand the rate and degree of nisin migration from the packaging materials as a function of the application conditions. Migration of nisin from polyamide coating binder was shown to be affected by the contact solution.…”

Advancing controlled release packaging through smart blending

“…28,29 Several categories of antimicrobials have been tested for antimicrobial packaging applications: organic acids, fungicides, bacteriocins, proteins, enzymes, inorganic gases, species, silver substitute zeolite, and others. 3,[27][28][29][30] Our research group has also studied the antimicrobial activities and release kinetics of packaging materials containing paraben, [31][32][33] triclosan 32,34 and nisin. 35 In general, the studies reported in the literature confirm that antimicrobial packaging is effective in inhibiting microbial growth and extending the shelf-life of food.…”

“…The release rate is slow when migration is governed by diffusion in the polymer matrix, and it is fast when governed by swelling or dissolution. 33,34 It is not uncommon that a large portion of the active compound incorporated in these materials will never be released, because of the closely packed structures of polymer matrices and/or strong affinity between active compound and polymer. A new approach is needed to overcome the limitations of existing materials and film technologies.…”