The purpose of this study was to extract phenolic compounds and antioxidant activity from buckwheat with water, 50% aqueous ethanol, or 100% ethanol using microwave irradiation or a water bath for 15 min at various temperatures (23-150 °C). Phenolic content of extracts increased with increasing temperature. In general, phenolic contents in microwave irradiated extracts were higher than those heated with a water bath. The highest phenolic content, 18.5 ± 0.2 mg/g buckwheat, was observed in the extract that was microwave irradiated in 50% aqueous ethanol at 150 °C. The highest antioxidant activities, 5.61 ± 0.04-5.73 ± 0.00 μmol Trolox equivalents/g buckwheat, were found in the 100% ethanol extracts obtained at 100 and 150 °C, independent of heat source. These results indicate that microwave irradiation can be used to obtain buckwheat extracts with higher phenolic content and similar antioxidant activity as extracts heated in a water bath.
|Original language||English (US)|
|Number of pages||4|
|State||Published - Apr 1 2010|
ASJC Scopus subject areas
- Analytical Chemistry
- Food Science