Optimizing packaging 445 The VTT Concept uses mathematical modelling to determine the minimum package requirements for the foodstuff. The modelling of the shelf-life of foodstuffs is performed in the following steps: (1) selecting factors and responses,(ii) selecting the experimental design method (screening or more extensive method),(iii) carrying out tests, (iv) analysing results,(v) making shelf-life predictions and(vi) determining the minimum package requirements The factors that might be relevant and might affect the quality deterioration of the foodstuff are chosen, for example, oxygen transmission rate of a packaging material, carbon dioxide concentration of a package, ge volume and storage conditions(temperature, illumination, etc. ) The parameters In shelf-life testing of food can include sensory and analyses and microbiological determinations. The minimum package requirements can also be based both on the information of the shelf-life tests and on the literature data 21.3. 2 Determining different package and storage combinations After the required packaging parameters for a foodstuff at certain storage conditions have been determined, it is possible to select the different alternatives of packages and packaging materials, packaging methods and package conditions all of which give equally acceptable food quality at the end of the required shelf-life of the product (e.g. vacuum or gas-flushed package wit specified packaging material and gas concentrations) 21.3.3 Scoring the selected alternative package type The selected, alternative package types giving the same minimum required shelf-life, are first scored by rating different characteristics of each package type. As an example, the following package attributes can be used in a Precision Packaging Concept mechanical strength of a package suitability with respect to packaging standards ratio of package weight to product weight volume of package waste ibility of incineration life cycle assessment of packages marketing properties of a package consumer convenience consumer attitude cost of packaging material indirect packaging cos All these characteristics are scored on a scale from I to 5, with I corresponding to poor and 5 to excellent quality. Fractional numbers are also allowed. The scoring is performed in co-operation with experts representing wholesalers, food manufacturers, packaging material manufacturers and independent specialists of ackaging technology and plastics industryThe VTT Concept uses mathematical modelling to determine the minimum package requirements for the foodstuff. The modelling of the shelf-life of foodstuffs is performed in the following steps: (i) selecting factors and responses, (ii) selecting the experimental design method (screening or more extensive method), (iii) carrying out tests, (iv) analysing results, (v) making shelf-life predictions and (vi) determining the minimum package requirements. The factors that might be relevant and might affect the quality deterioration of the foodstuff are chosen, for example, oxygen transmission rate of a packaging material, carbon dioxide concentration of a package, package volume and storage conditions (temperature, illumination, etc.). The quality parameters in shelf-life testing of food can include sensory and chemical analyses and microbiological determinations. The minimum package requirements can also be based both on the information of the shelf-life tests and on the literature data. 21.3.2 Determining different package and storage combinations After the required packaging parameters for a foodstuff at certain storage conditions have been determined, it is possible to select the different alternatives of packages and packaging materials, packaging methods and package conditions all of which give equally acceptable food quality at the end of the required shelf-life of the product (e.g. vacuum or gas-flushed package with specified packaging material and gas concentrations). 21.3.3 Scoring the selected alternative package types The selected, alternative package types giving the same minimum required shelf-life, are first scored by rating different characteristics of each package type. As an example, the following package attributes can be used in a Precision Packaging Concept: • mechanical strength of a package • suitability with respect to packaging standards • ratio of package weight to product weight • volume of package waste • possibility of incineration • life cycle assessment of packages • marketing properties of a package • consumer convenience • consumer attitudes • cost of packaging material • indirect packaging costs. All these characteristics are scored on a scale from 1 to 5, with 1 corresponding to poor and 5 to excellent quality. Fractional numbers are also allowed. The scoring is performed in co-operation with experts representing wholesalers, food manufacturers, packaging material manufacturers and independent specialists of packaging technology and plastics industry. Optimizing packaging 445