Multi-layer packaging functional barriers

It is generally known that only a very limited number of packaging materials such as glass or metal provide absolute protection properties concerning the penetration of chemical compounds from layers behind or from the environment. In the case of multi-layers with plastics materials as functional barriers there occurs, in most cases to a certain extent, an unavoidable mass transfer from the plastics layers into the product. This must be understood as a functional quantity which, however, must comply with food regulations. Therefore it is necessary firstly to understand functional barrier characteristics and mechanisms and, secondly, to define the functional barrier efficiency in relation to food safety and to establish appropriate test methods. This is especially important with those food packaging applications where recycled plastics are covered by plastics functional barriers. 

J. SIMAL-GANDARA, M. SARRIA-VIDAL, R. RIJK, Tests of potential functional barriers for laminated multi-layer food packages. Part II Medium molecular weight permeants. Food Additives and Contaminants, 2000, 17(9), 815-819. 

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