| dc.description.abstract | This study aimed at investigating the effects of microwave treatment , ultrasound
treatment and the water-to-powder ratio on the efficiency of extraction of oil from
fresh avocado fruit pulp. The samples were treated with microwave power (400-
800W), microwave time (15-60 seconds), ultrasound temperature (30-60oC),
ultrasound time (15-60 minutes) and water-to-dry matter ratio (6-10 mL/g). The
optimal conditions for each factor were determined by measuring the highest oil
yield and the physiochemical properties of the final oil were evaluated. The best
conditions for fresh avocado pulp extraction in this study were observed under
microwave treatment (45s, 800 W), sonication temperature (30oC, 30 min), and
a water-to-dry matter ratio of 6 mL/g, of which the extraction oil yield was 36.50%
(d.b.). Compared to Soxhlet-extraction of avocado oil, which gave yield of 56.60%
(d.b.), the oil yield was approximately 20.1% less in the microwave combined with
ultrasound extraction. However, the quality oil was higher in terms of lower free
fatty acid value, peroxide value and a higher iodine and saponification values. The
color of microwave-ultrasound extracted oil was lighter than that of Soxhlet
extraction. Additionally, the solvent used for oil extraction, i.e water, is a type of
green solvent. Overall, the avocado oil extraction with the assistance of microwave
and ultrasound can be applied, using water as a green solvent. | en_US |
