Flexographic and screen printing of carboxymethyl chitosan based edible inks for food packaging applications

In this study, carboxymethyl chitosan (CMC) based edible inks were prepared and the flexographic and screen printing properties of the inks were investigated. The water soluble carboxymethyl chitosan was prepared through a one-pot, environmental-friendly method in an alkali/urea mixture. The monascus pigment was then mixed with the carboxymethyl chitosan to obtain the inks. The inks showed good printing quality (e.g. pH, scratch resistance, optical density, contact angle and chromatic value) on coated paper after flexographic and screen printing. Also, the obtained inks, with excellent antibacterial activity against E. coli and S. aureus, demonstrated great printing effect on different substrates including different foods. We believe that this water soluble chitosan based edible inks may have potential applications in different food and medical packaging fields.