Evaluation of nisin diffusion in a polysaccharide gel: Influence of agarose and fatty content

The present paper investigated the nisin mass transfer in agarose gel. Nisin is a conservator molecule involved in food safety by inhibiting growth of pathogenic and spoliage bacteria. Nisin's apparent diffusion coefficients and the gel texture were determined and correlated to both agarose and vegetaline® (hydrogenated coprah oil) content. As a result, increasing agarose content decreased nisin diffusivity. Vegetaline® seemed to have no impact on nisin mass transfer even if Young's modulus was decreased when it was added to agarose gel.Industrial relevanceNisin, an antimicrobial with membrane permeabilizing properties, needs to reach microbial surfaces to be effective. Consequently, this study dealing with the diffusion properties of model food matrices is relevant for predicting antimicrobial efficacy. In agreement with the authors statement, additional studies with model gels closer in composition to real foods than the agrose gels selected seem necessary to properly assess nisin diffusivity through food matrices.