| dc.description.sponsorship | Pumpkin seeds (Cucurbita ficifolia) contain rich oil, which is considered as a rich source
of bioactive compounds. Although pumpkin seed oil obtained from mechanical cold
pressing expressed is of good quality, however, some treatmnents may help to
increase both oil yield and quality. This study aimed to investigate the effect of
different roasting methods for pumpkin seed oil to investigate the yield, quality
physicochemical and bioactive properties of cold-press oil from different methods. In
the present study, pumpkin seed was roasted by 3 methods including pan, hot air flow
and microwave roasting before cold-pressing. The cold-pressed was conducted at
pressure of 20 MPa at room temperature, using a custom-made device. The pan, hot
air flow and microwave roasting methods were compared by the extraction yield and
several quality indicators such as peroxide values, iodine value, free fatty acid values,
and bioactive properties such as total phenolic content and antioxidant capacity.
Theperoxide values, free fatty acid values and the yields were significantly different
among 3 methods. The oil obtained by cold-pressed was most against oxidation and
rancidity. The best oil product by using cold press extraction got a highest oil yield
(27.3%) of microwave roasting 240W in 40 seconds and a good quality with free-fatty
acid value (3.29 as % oleic acid) of pan roasting at 200oC in 5 minutes, peroxide value
(5.75meq O2/kg) of hot-air roasting at 200oC in 9 minutes, iodine value (78.75 g
I2/100g) of microwave roasting at 240W in 40 seconds, total phenolic content
(84.56mgGAE/100g) of hot air flow at 200oC in 9 minutes and antioxidant capacity
(45.79%)of microwave roasting at 240W in 40 seconds. In general,it could be
concluded that hot air flow and microwave roasting was better on oil yield, peroxide value, total phenolic content and antioxidant capacity than pan roasting. In other
cases, pan roasting resulted in higher free fatty acid value than hot-air roasting and
microwave roasting. | en_US |
