Kinetics of colour changes in pasteurised strawberry juice during storage

Colour changes during storage are an important quality defect of fruit-based products. Therefore, this work investigated the effect of storage time, storage temperature and oxygen availability (through the type of bottle) on changes in CIEL*a*b values, anthocyanin and ascorbic acid content of shelf-stable strawberry juice (produced with a spiral-filter press under vacuum conditions) using kinetic modelling. The colour-related attributes changed significantly during storage at ambient (20 degrees C) and accelerated temperatures (28-42 degrees C) in both types of bottles. The change in all attributes was accelerated at higher storage temperatures. A higher oxygen availability resulted in a faster change of all attributes. As oxygen availability was not fully controlling colour changes, they are caused by complex oxidative and non-oxidative reactions. The results of this work demonstrate the applicability of a kinetics-based accelerated shelf-life testing approach to obtain faster insight into colour changes of strawberry juice and to be used for shelf-life investigations. (C) 2017 Elsevier Ltd. All rights reserved.