##plugins.themes.huaf_theme.article.main##
Abstract
The aim of this study was to investigate the effects of thermal processing (100, 200 and 300℃ in 1, 2 and 3 minutes) and mixing ratio (flower, stem, ginger, stevia and green tea) on the quality of tea bags from flowers and stems of bo chinh Ginseng based on chemical criteria (saponins, polyphenols) and sensory criteria (color, smell, taste). The results showed that bo chinh ginseng flowers and stems were pan-fired at 200°C for 1 and 3 minutes, respectively, achieving the highest sensory value. The saponin content remains respectively at 84.4% and 76.9% in thermally treated flowers and stems. The polyphenol content retained in flowers and stems after the thermal process is 11.6% and 69.0%, respectively. The highest total sensory score was recorded in the mixing formula 6 with the mixing ratio of flower: stem: ginger: stevia: green tea respectively 1.1: 0.6: 0.1: 0.1: 0.1. The Bo Chinh gingsen tea bag had an antioxidant activity, although this activity was lower than that in the flower and stem materials. The products contain protein, total sugar, total lipid, especially saponin and polyphenol. Their moisture content, total ash and microbiological criteria meet the safety threshold according to Vietnamese standard for herbal tea bags.