Effect of Packaging Materiales, Storage Conditions, Cultivar and Extraction Methods on The Extraction Quality of Roselle Calyxes

Document Type : Original Article

Authors

1 Food Tech. Res. Inst., Agric. Res. Center, Giza, Egypt.,

2 Department Medicinal and Aromatic Plants, Agricultural Research Center, Dokki, Giza. Egypt.

Abstract

Effect of packaging materiales, extraction methods and storage period on some quality of two cultivars of Roselle calyxes extracts has been studied. Dark red and light red Roselle calyxes packed in- low density polyethylene (LDPE) and Glass bottles and stored for eight months at room temperature. Two methods were carried out for preparation of Roselle extract from both dark and light cultivars. Soaking in distilled water or acidic water (2% citric acid) at different temperatures (5, 20, 60 and 100 0C) for several periods (1/2 : 24 hrs). The packaging type, cultivars of Roselle, extraction method soaking temperature, soaking period and storage period were highly significant effect for TSS, and anthocyanin, but there are no significant different in pH value with packaging type or extraction method. T.S.S. content was found to be increased by increasing soaking temperature, soaking period and storage period for both  dark and light cultivars packed in (LDPE and Glass bottles) and soaked in distilled water or acidic water (2% citric acid). High total soluble solids content was recorded for dark red cultivar packed in low density polyethylene (LDPE)  and extracted with acidic water (2% citric acid) at 100 0C  for 90 min.The PH values of Roselle calyxes extract was found to be  depending on soaking temperature, soaking period and  storge time.The pH value of light Roselle calyxes extract was less than that of dark red Roselle calyxes extract with all treatments. High decreament in pH value of Roselle calyxes extract was recorded for light red cultivar packed in glass bottle  and extracted with acidic water (2% citric acid) at 100 0C for 90 min. Anthocyanin value increased in Roselle calyxes extracts of both dark and light cultivars with increasing soaking temperature and soaking period in both water or  acidic water (2% citric acid) but decreased with increasing storage period.  

Main Subjects