Application of Active and Edible Films of Sodium Caseinate to Extend the Shelf-life of Argentine Pategrás Cheese

Argentine Pategrás cheese is one of the most popular types of cheese in Argentina. The main spoilage causes in these products are microbiological contamination and lipid rancidity. Semi-hard cheeses are usually covered with a paraffin wax that favors its preservation. When pieces are stored, cutting faces must be protected to prevent desiccation and contamination. Active biodegradable films are an alternative to the traditional materials, in particular, casein-based edible films are attractive for food applications. In the present work, active films of sodium caseinate with oregano (Origanum vulgare) and laurel (Laurus nobilis) essential oils were produced for packaging a processed Pategrás cheese. Aseptical portions of these were packaged by heat sealing, the samples were stored under shelf conditions (12.8 °C and 70-80% RH) for 56 days. Portions were periodically removed from storage and microbiological count of mesophilic microorganisms, food pathogens like S. aureus, as well as fungi and yeasts determination were made on samples surfaces. The results showed the highest antimicrobial activity of films with oregano essential oil. Subsequently the sensory analysis of packaged cheeses was made; those involved with active films with essential oils, were the freshest at the end of shelf life and showed the highest acceptability by the sensory panel members throughout the study period