Quality changes during storage of fresh-cut or intact Swiss chard leafy vegetables

Fresh-cut leafy vegetables have been gaining importance in the human diet both their nutraceutical proprieties and low calories content. The preparation procedures for fresh-cut production and the storage system may lead to severe leaf damages that may affect leaf colour and may induce shortened shelf life. The aim of this work was to study the leaf pigment changes in cut and whole Swiss chard leaves under dark or light storage conditions. The effect of treatments was evaluated by chlorophyll, carotenoids and anthocyanins determinations. The leaf membrane integrity was estimated by electrolytes leakages. All measurements were performed until 12 days of storage. The chlorophyll reduction was statistical significant in cut Swiss chard leaves stored in darkness. Total carotenoids did not statistically decline. Anthocyanins content strongly declined in cut leaves in both dark and light storage conditions. Leaf electrolytes leakage increased after 8 days of storage and higher leakage was observed in Swiss chard stored in light conditions without any difference between cut or whole leaves. Results suggest that Swiss chard can be stored until 8 days without any visible changes. Dark storage seemed to preserve quality losses and reduce membrane permeability.