Flowers of Ulex europaeus L. - Comparing two extraction techniques (MHG and distillation)

Microwave hydrodiffusion and gravity (MHG) extraction of Ulex europaeus was proposed for the production of extracts. The extraction time and yield and the antioxidant and sensorial properties of the extracts were significantly affected by the irradiation power. MHG treatment at 100 W during 76 min provided optimum yields and the extracts showed the highest reducing power and antiradical activity. The extraction time could be reduced in relationship to that needed with steam distillation (153 min) to reach comparable extraction yields and retaining the antioxidant properties. The flower extracts from the two tested technologies showed similar color (colorless) and olfactometric characteristics (floral and ripe fruity aroma).