Page 490 - Biosystems Engineering

462 Cha pte r S i x tee n

(Ozer et al. 1996), cloudberry seed oil (Manninen et al. 1997), sun-
flower oil (Perrut et al. 1997), almond oil (Marrone et al. 1998), pista-
chio nut lipids (Palazoglu and Balaban 1998), rapeseed, sunflower
and soybean (Bjergegaard et al. 1999), corn bran (Taylor and King
2000), grapeseed oil (Lee et al. 2000), hiprose seed oil (Reverchon et al.
2000), lavender essential oils and waxes (Akgun et al. 2000), and
Romanian mentha hybrids oil (Eugenia and Danielle 2001).
Rice bran lipid extraction with supercritical fluid is also reported.
Figure 16.3 shows a pilot-scale SFE extraction system. Zhao et al.
(1987) studied fractional extraction of rice bran oil at 40°C and
obtained an oil yield in the range of 18.6 to 22.0 percent with pressure
variations ranging from 14.7 to 34.3 MPa. Fractions obtained with
SFE contained 8.8 percent free fatty acids compared to 11.9 percent
for hexane-extracted oil. Ramsey et al. (1991) compared rice bran oil
extraction with hexane, SFE (29.99 MPa, 35°C, 5 h, 20.5 g/min) and
SFE with cosolvent (29.99 MPa, 35°C, 5 h, 20.5 g/min, 5 percent
ethanol) extraction processes. He was able to recover 20.2, 18.0, and
18.2 percent oil yield; sterol yields were 9.4, 7.3, and 8.3 mg/g of rice
bran for hexane, SFE, and SFE–cosolvent extractions, respectively.
Garcia et al. (1996) recovered 16 to 60 percent of solvent extractable
oil from rice bran at 28 MPa and 70°C. Kuk and Dowd (1998) reported
19.2 to 20.4 percent RBO yield in SFE extraction (48.26 to 62.05 MPa)
compared to 20.5 percent in hexane extraction. Xu and Godber (1999)
compared solvent extraction (50 percent hexane and 50 percent
isopropanol v/v) of rice bran with supercritical carbon dioxide extrac-
tion (50°C and 68.9 MPa) for γ-oryzanol fractionation. Their study

FIGURE 16.3 Pilot-scale SFE system for extraction of rice bran oil (Patel 2005).