Influence of cardboard coating on solvent retention

Abstract

Packaging has a barrier function between the product and the environment. Flavour and taste changes in food products due to the transfer of undesirable volatile compounds from gravure printed cardboard packaging should be avoided. In this study, the influence of cellulose-based, folding boxboard (FBB) type cardboard coating on solvent retention was studied by gas chromatography (GC). FBB samples with 1-3 and no coating layers on the top side, and with coated or uncoated back side, were printed by rotogravure. Then, solvent retention was measured at 3 different time intervals. Ethanol and ethyl acetate contents were studied more in depth in order to obtain information on the emission behavior of alcohol and ester type solvents from the cellulose-based cardboard. Based on GC results, ethanol and ethyl acetate retention ratios were calculated and then normalized to coating thickness for every time interval, aiming to see the solvent retention differences as a function of the number of coating layers applied onto the cardboard surface. It was found that the number of coating layers on the cellulose-based cardboard top and back sides has a clear influence on solvent retention and emission on/from printed packaging. Therefore, it can be considered as a significant variable in solvent retention analysis.