4. Conclusion
In
the present work, AEE process proved to be effective in extracting RBO.
Alcalase 2.4L was found to give higher oil yields than Celluclast 1.5L,
Hemicellulase, Pectinex Ultra SP-L, Viscozyme
L.
Comparisons of the physicochemical characteristics of AEEO with those of
SEO revealed that different extraction methods had influence on the
quality parameters of RBO. Briefly, iodine value, saponification value
in the AEEO were found to be higher than SEO. AEEO had lower acid value
and peroxide value which was considered to be a high quality oil. The
content of wax and phospholipid in AEEO was lower, which could simplify
the refining steps.
In
addition, GC-MS results showed that AEE increased the amounts of
unsaturated fatty acids compared with SE. A comparison of the content of
bioactive compounds showed that RBO extracted by the AEE was more
abundant in
vitamin
E, sterols, squalene and oryzanol.
DSC results indicated that the different methods used for oil extraction
caused the variations in the melting and crystallization behaviour of
RBO. In comparison to the SEO, AEEO
were found to have lower crystallization and melting points. Moreover,
SEM
results demonstrated that the destruction of cell walls and the decrease
of substances in the cell by AEE.
These
results suggested that AEE offers an efficient, environment friendly and
easy procedure of RBO extraction and the oil produced by this emerging
method can be used as high-quality edible oil in food industry.