POLYETHYLENE PACKAGING WITH SILVER AND ZINC MICROPATICLES AND ITS INFLUENCE ON MILK QUALITY

Protection of milk and dairy products from the effects of microorganisms and surface spoilage by the introduction of antimicrobial additives into packaging materials is a relevant and promising method. This publication is devoted to the preparation of a microparticle-modified ECOS preparation (silver salts and oxide) of a polyethylene package, the study of its properties and effects on the composition of milk. The basic physicochemical and microbiological parameters of milk during storage, as well as the possible migration of microparticles into milk and model liquids were studied by the methods of elemental analysis, scanning electron microscopy, and laser dynamic light scattering. It was found that such indicators as the content of fat, protein, lactose, dry substances remain unchanged within the experimental error for the initial milk, milk aged for 24 h in a glass container, and in contact with the modified polyethylene. When stored in glassware at room temperature (24 °C), the number of mesophilic aerobic and facultative anaerobic microorganisms in a day amounted to 8.1 · 106 CFU/cm3, while the number of bacteria in the package with ECOS was 6 times less. It was found that the silver content in milk in contact with the modified polyethylene is negligible. The amount of zinc increases within 24 h by 10%, which is not critical in terms of milk quality indicators. It is shown that storing milk in a polymer package made with ECOS preservatives allows to suppress the development of microorganisms in cow milk, does not lead to any significant change in its composition and does not affect the quality.