Technological watch

Composite film prepared using PVA, pectin form passion and lime peel had excellent mechanical, optical, thermal and bioactive properties. This film was used to pack strawberries and plums during chilled storage. Active film could significantly increase the shelf life of both the fruits.ABSTRACTPectin from lemon and passion fruit peels was studied for its potential to serve as a source of biopolymer for preparation of active film. To develop a packaging film appropriate for fruits, different combinations of polyvinyl alcohol (PVA), pectin from lemon and passion fruit peel and rosemary essential oil (REO) were evaluated. Extensive characterisation of these films with respect to colour, thickness, moisture, opacity, UV absorption, tensile strength, elongation, swelling, solubility and thermal and chemical interactions was studied. Film prepared with PVA, lime and pectin peel (2:1:1?v/v) without REO and glycerol as plasticiser was found to be best based on the above properties. Additionally, the effectiveness of this film at extending the shelf life of strawberries and plums was evaluated. Physiological changes on storage were lesser in active packaged fruits as compared to unpackaged fruits. On basis of several spoilage indices studied, unpacked fruits had shelf life of less than 7?days, while those packed in active film were acceptable up to 15?days in case of strawberry and 45 in case of plums when stored at chilled temperature (6°C). Thus, use of the developed active packaging film would be beneficial for extending the marketable period of the fruits and enhancing its cost?effectiveness.