Active coating for storage of Mozzarella cheese packaged under thermal abuse

A novel antimicrobial packaging system, as active coating on a commercial Poly(ethylene terephthalate) (PET) film, was formulated and tested in vitro against the spoilage bacteria of Mozzarella cheese. It is based on layered double hydroxide (LDHs) intercalated with salicylate and carbonate anions dispersed in a solvent-based heat seal. The population of spoilage microorganisms (total coliforms, Pseudomonas, fungi), along with the functional microbiota of Mozzarella cheese (lactic acid bacteria) was characterized. Microbial shelf life was evaluated at 18 °C, to simulate thermal abuse. Experimental results show an increase in the microbial shelf life of the packaged Mozzarella cheese of about 20 days, confirming that the investigated active coating may exert an inhibitory effect on the microorganisms responsible for spoilage phenomena, without affecting the functional microbiota of the product.