Effect of moisture content on tensile properties of paper-based food packaging materials

Tensile properties (tensile strength and elongation at break) of 3 selected paper-based packaging materials, such as a vegetable parchment (VP) paper, a Kraft paper, and a solid-bleached-sulfate (SBS) paperboard, were determined with varying moisture contents. The monolayer moisture content of the paper samples determined using the Guggenheim-Anderson-de Boer (GAB) model were 3.45, 3.01, and 3.18 g water/100 g solids for the VP paper, the Kraft paper, and the SBS paperboard, respectively. Tensile strength and flexibility of paper samples was greatly influenced by the moisture content depending on the paper materials and paper manufacturing directions. However, the tensile properties of the paper samples maintained up to the monolayer moisture content, which corresponds to the water activity (Aw) of around 0.4 at 25°C.