Concerning the comparison of the five techniques in termsof total extraction time and yield, combined UAE–HD techniques(ultrasound assisted extraction followed by hydrodistillation) wereclearly fast (≤1 h) while 6 h were required for full extraction ofessential oil from cardamom seeds by traditional hydrodistilla-tion. Time of hydrodistillation with or without ultrasound assistedextraction was set when no more essential oil was obtained. Thecombined technique 3 provided significantly higher extractionyield compared with that obtained by HD. On the other hand, theultimate yield of cardamom essential oil obtained by other com-bined UAE–HD techniques were not significantly different fromthat obtained by means of HD. Results are in agreement withthose reported by Assami et al. (2012) who found that ultrasoundtreatment engenders a rapid release of essential oil after only30 min of extraction for treated Carum carvi L. seeds versus 90 minfor untreated seeds. Pingret et al. (2014) reported that the use ofultrasound allowed the recuperation of the same amount of orange