Abstract:
Non-swelling clays have been used in traditional paper coating technologies for many years because these exert the least effect on the rheological properties of a formulate coating. However, recent work has demonstrated that combining swelling clays, particularly the smectites, with starch and plasticisers to form a sustainable coating, results in water vapour transmission rates (WVTR) that are competitive with oilderived barrier coatings. Coatings with high barriers to gases, vapours and flavours find their major application in food packaging materials. Taking into account the amount of food currently wasted every year, packaging that keeps it fresh for a longer time has an important role to play in reducing the amount of energy consumed during the food production and transport cycle.