TRANSPORT OF OLEIC AND ACETIC-ACIDS FROM EMULSIONS INTO LOW-DENSITY POLYETHYLENE - EFFECTS ON ADHESION WITH ALUMINUM FOIL IN LAMINATED PACKAGING

Three test emulsions were prepared by adding oleic acid and/or acetic acid to a fatty food simulant (oil-in-water emulsion) from rapeseed oi l, using Tween-80 as emulsifier. These test emulsions and the blank we re packed in laminated material and stored for 4 wk at room temperatur e (21 degrees C). Sorption of oleic acid into LDPE and the rate of ace tic acid permeation through LDPE were highest for emulsions containing both oleic and acetic acids. A complete delamination within 4-7 days occurred for all acid-containing test-emulsions, probably caused by fo rmation of a weak boundary layer (WBL).