Effects of Temperature and Solid-liquid-ratio on the Extraction of Total Phenolic Content of Hibiscus sabdariffa leaves

Abstract

Hibiscus sabdariffa leaves (HSL) can be used as tea leaves because of its bioactive compounds. This study demonstrates the effects of extraction temperature and solid liquid extraction ratio on the total phenolic content (TPC) of HSL. The HSL was harvested, washed dried with vacuum dryer at 40 °C and ground. The resultant powder was characterized in terms of tapped and bulk density, Carr’s index and Hausner ratio to ascertain its flow characteristics prior to the extraction using distilled water as the extraction medium at 70, 80and 90 °C and at the solid-liquid ratio of 1:9 and 3:7. The bulk and tapped density of 212m were 20.29 ± 0.1753 g/ml  and 25.58 ± 0.2700 g/ml respectively .The carr index and Hausner ratio  were 20.67 ± 1.154 and 1.26 ± 0.0185 respectively. Maximum extraction TPC was observed at 90 °C and at the solid-liquid ratio of 1:9 while the least TPC was observed at 70° C at 3:7 solid-liquid ratio.