water and then allowed to settle. Aqueous phase (clear and oil free)
was discarded, and the oil was decanted. Then the oil was kept in
hot air oven for 2 h at 105 C until constant weight was obtained.
For comparison, ultrasound-assisted aqueous extraction of rice
bran oil was done with the similar procedure as described above.
The sample before centrifugation (tabletop centrifuge) was
immersed in ultrasound bath with power of 60 kHz for a specific
time (15–90 min) at constant temperature. All experiments were
conduct in three repetitions. Oil extractability was calculated using
below formula and expressed as a percentage of the initial oil
content:
% Oil extractability ¼ weight of oil extractedðgÞ
100=weight of initial rice branðgÞ