Determination of Packaging Material Requirements for Optimum Shelf Life of Packaged Filled Milk Powder

Packaging plays an important role in protecting and preserving the quality of food and is therefore significant in any food manufacturing and distribution process. The shelf life of any food is limited due to the occurrence of many deteriorative processes and reactions within the food material. These include physical and chemical reactions and interactions between food and the ambient environment across the packaging material. Milk powder like any other food, is prone to such reactions and interactions with package resulting in degradation of its edible quality due to changes in smell, colour and texture, which ultimately renders it nutritionally and economically unacceptable. During distribution and storage the packaging system needs to stabilize the powder by ensuring optimum storage conditions are maintained. To ensure maximum shelf life it is essential to apply packaging systems that are optimally designed, to meet the requirements with respect to manufacturing as well as product protection in the distribution environment. In this thesis, the interactions between ambient environmental conditions, packaging material properties and the shelf life of a particular filled milk powder were investigated. Consequently, the requirements for a packaging system that can provide a two-year shelf life for the powder were determined. The filled milk powder is manufactured and packaged in bulk in Europe, imported into Africa via sea freight containers to be repacked into small portion packs and distributed in multiple African countries. Because of Africa's tropical conditions the packaged product is exposed to rather high levels of relative humidity and temperature during transportation and storage which influences the stability of the powder. The storage stability of the filled milk powder along with the barrier characteristics of the packaging was assessed in order to evaluate the theoretical shelf life of the powder in its current packaging system