The durability of press-formed paperboard trays – Effects of sealing and drying

Dimensional measurements were recorded to observe the durability of press-formed paperboard trays used for food processing via heating and cooling of the paperboard trays containing oatmeal. A set of the studied press-formed paperboard trays were dried before being heated, and a set of the paperboard trays were heat-sealed before being cooled to compare the effects of drying and sealing on the durability of the tray. In addition, empty trays were heated to observe the impact of food processing conditions on its durability via leak tests with a colouring solution as well as optical analysis of the material coating on the surface of the trays. The drying process of the trays was observed to improve the dimensional stability of the trays while being heated, and heat-sealing the trays yielded a major positive impact on the dimensional stability of the trays while being cooled. The leak tests and optical analysis results on the heated empty trays showed a negative durability impact from the food processing conditions. It was concluded that adjusting the heat-sealing parameters and food processing conditions is necessary in order to achieve improved durability of the press-formed paperboard trays for food processing purposes.