POST-HARVEST STUDIES ON REDUCING LOSSES AND MAINTAINING QUALITY OF PACKAGING ROSELLE CALYXES

Document Type : Original Article

Abstract

The post-harvest technologies of roselle must be developed to maintaining quality. There are no appropriate structures for the shelling ,drying, packaging and storage for the calyxes of Hibbiscus sabdariffa L and it appears that these operations are performed under unsuitable conditions leading to the deterioration of the quality of the Hibbiscus sabdariffa , Lcalyxes .For this, the effect of shelling methods ( hand and tools) ,drying processing (sun and oven drying), packaging materials and storage period on some quality of two cultivars of roselle calyxes extracts was studied. Dark and light roselle calyxes removed the seed’s capsules for obtained fresh roselle calyxes one shelling hand and the other tool shelling, and the after that drying is carried out after shelling by two ways first is sun drying and second way is
an oven air dryer at 55Co for 36 hours to obtain 11% moisture content of dried roselle calyxes. All previously treatment of dark and light red roselle calyxes were divided into two groups randomly assigned to each of the treatment
combinations one were packed in polypropylene (pp) package and the other packed in glass bottles as three hundred gram of each sample and stored for eight months at room temperature. Cultivars of roselle calyxes extracts, the
packaging materials and storage period were highly significant effect for TSS, total acidity and pH but there are no significant different in anthocyanin with drying processing The two, three and four-way interactions were highly
significant for TSS, total acidity and anthocyanin. Total soluble solids content was found to be increased by increasing storage period for both dark and light red roselle cultivars dried by (sun and oven) and packed in (polypropylene and glass bottles). Higher total soluble solids content was recorded for dark cultivar dried by oven packed in glass bottles after 8 months of storage. PH value for dark and light red roselle calyxes decreased with the increase in storage period for the two cultivar with two packaging material and two drying methods from zero days to the end of storage (after 8 months). The pH values of dark roselle extracts was higher than that of light red roselle extracts with all treatments. Dark and light red Roselle calyxes packaged in polypropylene showed pH values largest compared with packaged in glass bottles. The pH
values of dark and light red roselle calyxes extracts dried by sun was less than that dried by oven for two packaging materials after 8 months of storage. Anthocyanin value decreased in roselle calyxes extracts of both dark and light
cultivars with increasing storage period with all treatments. Anthocyanin value for dark cultivar was higher than the light cultivar. Dark and light roselle calyxes extracts packaged in polypropylene had anthocyanin value higher than that packaged in glass bottles during storage periods. Total acidity of dark and light roselle calyxes extracts increased with increasing storage period for all treatments. The dark roselle calyxes recorded the higher titratable acidity than light red roselle calyxes for all treatments during storage period. Titratable acidity of dark and light red roselle was highly with roselle calyxes dried by oven for two packaging materials throughout storage. Roselle calyxes packed in (pp) gave the lowest value titratable acidity as compared with roselle calyxes extracts packed in glass bottles for two cultivars.

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