Packaging Design And Software Development For Food Moisture-proof And Oxidation-proof Package

All foods are susceptible to quality and safety losses during the processes of production, distribution and consumption. The shelf life of food package can be obtained or extend by applicable packaging technology, which can prevent or delay the quality reducing. In this paper shelf life prediction models for moisture-proof package and oxidation-proof package are developed and some results are obtained.Silica gel, montmorillonite and rice cracker were studied as test subjects, and the relationship between the water activity and the equilibrium moisture content were studied by the gravimetric method. According to the scope of the activity and the effect of the fitting agreement, the Langmuir, Oswin and Oswin models are the most suitable for fitting the isotherms of silica gel, montmorillonite and rice cracker respectively. The moisture sorption kinetics was also characterized. The parameters of sorption rate were connected with relative humidity by mathematical modeling.A new model used for shelf life prediction of moisture-proof package was developed. The new model was based on the diffusion rate of packaging materials and sorption rate of contains. Both permeable and un-permeable materials are investigated. Predicted moisture contents and RH agree well with real time stability data. The new model could be applicable for accurate shelf life prediction.Another new model used for shelf life prediction of oxidation-proof package was developed. The new model was based on the diffusion rate of packaging materials and oxygen adsorbed and reacted rate of contains. An orthogonal test of the effect of packaging factors on shelf life was taken by computer simulation and the significant of each factor is ordered: the oxygen diffusion rate of packaging materials, the initial oxygen partial pressure in package, the volume of headspace of package. Based on the needed packaging permeability and the principle of ValueEngineering, a method for packaging material optimization design was proposed. The limiting conditions of this method are permeability of packaging materials, the maximum thickness of composite material or given materials for different position. Using the mathematical models and packaging design method, a software system of shelf life prediction and packaging design was developed.