Effect of alkaline pH values on physical and functional properties of edible films made from calcium caseinates

Abstract

Films are an important tool in food packaging, delivery, and preservation of food products. Milk based films have shown the potential to be renewable, edible, and provide a lower cost option to replace plastic films, but there is still a need to find formulations that have superior physical properties and can be made with cheaper materials. Research has suggested that pH modification of the film solution into alkaline conditions could improve film properties. Calcium caseinate based films were made with increased pH to study their physical qualities. Film strength for CaCN films reached a relative maximum at pH 8. CaCN films also showed increasing strength and decreasing elongation with aging. Increasing pH above 10 yielded the lowest oxygen permeabilities for both recipes. Calcium caseinate films with modified pH have many beneficial properties, performing better than previously reported milk-based films in a number of categories and are promising candidates for food applications.