Using polysaccharide-based edible coatings to enhance quality and antioxidant properties of fresh-cut melon

Abstract

The effect of alginate, pectin and gellan-based edible coatings on the shelf-life of fresh-cut ‘Piel de Sapo’ melon was investigated. Gas exchange, antioxidant properties, color, firmness, sensory quality and microbial growth of fresh-cut melon were studied during 15 days at 4 C. Gellan, pectin and alginate coatings increased the water vapor resistance of fresh-cut melon, thus preventing dehydration. They also had an inhibitory effect on ethylene production although O2 and CO2 diffusion through coated melon tissue was not avoided. Calcium chloride used as a crosslinking agent helped to maintain fruit firmness. Edible coatings themselves did not improve microbiological stability of fresh-cut ‘Piel de Sapo’ melon packaged under passive modified atmosphere. Pectin or alginate could reduce the wounding stress induced in fresh-cut melon, which triggered an accumulation of total phenolic compounds and other compounds with antioxidant properties. In addition, pectin-based coating seemed to best maintain sensory attributes.

This research was financed by the Ministerio de Ciencia y Tecnologı´a (Spain) through the AGL 2003-09208-C01 project, the European Social Fund and the Departament d’Universitats Recerca i Societat de la Informacio´ of the Generalitat de Catalunya (Spain) that also awarded author G. Oms-Oliu a predoctoral grant. We also acknowledge ISP International Corp., Barcelona, Spain for supplying the alginate employed in this work.