EXPERIMENT 1 WATER VAPOUR PERMEABILITY OF PACKAGING FILMS Prac Report Example

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EXPERIMENT 1 WATER VAPOUR PERMEABILITY OF PACKAGING FILMS 1. Aim To examine selected packaging materials for moisture permeability at 37oC and approximately 90% humidity. 2. Introduction Packagi... ng is used not only for the distribution of food products but also for protecting food products from deterioration caused by some major classes of external influences either biological or physical (Heiss & Eichner 1970). Besides that, chemical protection is also required in order to minimize compositional changes triggered by environmental influences such as moisture gain or loss, exposure to gases (typically oxygen) or light (Marsh & Bugusu 2007). There are various packaging materials available nowadays but not all of that can be used to package food products since each food product has different properties. By using proper packaging materials, it can be expected that the packaging can deliver products in the same quality as freshly prepared foods. Water vapour permeability of packaging materials is one factor influencing the quality of food products, typically dry food products such as crackers. Each packaging material has porous which is ranging in diameter size (Debeaufort et al 1994) and acts as membrane which when it is exposed to water vapour, the membrane chemically attracts the vapour and absorbs it (Jena & Gupta 2002). This is undesirable properties especially for dry food products since they have tendency to adsorb water vapour from the environment until the equilibrium moisture content reached as the moisture transfer from the ‘wet’ to the ‘dry’ system (Roudaut et al 1998). Therefore, it requires packaging materials which provide low gas permeability and good moisture barrier. 3. Materials and Methods Please refer to “FOOD7011 Practical Manual page 1 – Water Vapour Permeability of Packaging Films” for complete details of the experimental methods. Please note that only three packaging materials used, brown paper, polyethylene and cellophane. [Show More]

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