Toxic mineral oils can migrate into foods from cardboard boxes made of recycled fibers. This is an emerging issue for the whole dry-food-packaging industry. Breakfast cereals, for example, are typically packaged in boxes with or without inner bags and consumed without further processing. Currently, fossil-based high-density polyethylene (HDPE) films are used as a major raw material for such inner bags. However, HDPE is a very poor barrier against mineral-oil migration. Biobased coatings from cellulose nanofibrils (CNFs), hydroxypropylated xylan, and hydroxypropylated cellulose were applied onto biobased high-density polyethylene (bio-HDPE) films, and the mineral-oil barrier properties were evaluated. All of the coated films significantly decreased the migration of ndecane, isobutylbenzene, 1-cyclohexylbutane, 1-cyclohexylheptane, and 1-cyclohexyldecane. Biobased barrier bags prepared from (2,2,6,6-tetramethylpiperidin-1-yl)oxy oxidized CNF coated bio-HDPE film protected the content to a great extent from mineral-oil migration compared to noncoated bio-HDPE and other commercial breakfast cereal-bag films.
- biopolymers and renewable polymers
- cellulose and other wood products