| Summary: | The objective of this study was to validate the performance of the OnVuTM time temperature indicator (TTI) labels and prove the use of such labels under practical conditions during storage of cod loins, in both expanded polystyrene (EPS) boxes and retail packages. This was done by finding the appropriate initial charging value of the labels in agreement with the product time temperature history, finding a suitable position of the labels on the packages and by investigating whether the shelf life, as indicated by the colour change of the TTI labels, was in agreement with sensory, chemical and/or microbiological predictions of the shelf life of cod loins after different storage treatments. Three different storage treatments were studied i) a fresh cod supply chain scenario from packaging to consumption without abuse during transportation; ii) a fresh cod supply chain scenario from packaging to consumption with six-hour abuse during transportation and iii) a fresh cod supply chain back-up scenario from packaging to consumption including superchilled storage (whole simulation at Matis laboratory). Shelf lives predicted by TTI on bottom tray surface and predicted by the SSSP (Seafood Spoilage & Safety Predictor) square-root spoilage model (based on product temperature) were in good agreement for all storage treatments. Placement of TTI labels with the initial square value of 61 on the bottom surface of the retail trays stored at 0.5 C also gave similar shelf life as the product shelf life declared by sensory evaluation. It is therefore, suggested to stick the labels on the bottom of trays to monitor the shelf life of the product. The kinetic model of Kreyenschmidt et al. (2010) for TTI labels worked well with data from non-abuse storage at temperatures below 2 C, which indicates the potential to extend their quality contour diagram to low temperatures so that a charging level can be defined to suit the shelf life of a product stored under the same conditions. However, the shelf life predicted by the TTI labels ...
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