• International Journal of Automotive Technology
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• v.7 no.4
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• pp.399-406
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• 2006

The smoke emission of diesel engines is being recognized as one of the major source of the air pollution problems. This study investigates the potential of esterified rice bran oil to reduce smoke emission as an alternative fuel for diesel engines. Because the esterified rice bran oil has approximately a 10.5% oxygen content, the combustion of the diesel engine improved and exhaust smoke decreased. Gas chromatography was used to analyze not only the total amount of hydrocarbon but also the amount of hydrocarbon components from $C_1$ to $C_6$ in the exhaust gas to determine an exact source responsible for the remarkable reduction in the smoke emission. The number of individual hydrocarbon($C_1{\sim}C_6$) as well as the total amount of hydrocarbon of esterified rice bran oil reduced significantly compared to that of hydrocarbon of diesel fuel.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.207-211
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• 1996

This study was carried out to determine the lipid content and neutral lipid compositions of Japonica and indica rice bran oils. The average content ratio of neutral lipids, g]ycolipids and phospholipids were 89.5 : 4.0 : 6.5 in japonica rice bran oil and 93.7 : 2.6 : 3.7 in Indica rice bran oils, respectively. It was seen that the neutral lipid content was significantly higher in JAponica rice bran oil, while the contents of glycolopods and phospholipids were significantly higher in japonica rice bran oils. The neutral lipids consisted of esterified sterol, triglyceride, free fatty acid, free sterol, diglyceride and monoglyceride. Triglyceride was the highest (48.7-49.7%) among the neutral lipids. Major fatty acids of rice bran oils were oleic (39.65-43.68f)), linoleic (32.62-39.42%) and palmitic acid (16.54-18.83%). The linoleic acid content was higher in Japonica rice bran oils than in indica rice bran oils.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.180-185
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• 1985

The alkali refined rice bran oil (ARBO) and the esterified rice bran oil (ERBO) with glycerol were compared for their thermal stabilities at $150^{\circ}C$ and $180^{\circ}C$, respectively. The acid value gradually increased in ARBO during heating period but increased slowly in ERBO-2 and declined gradually in ERBO-1. The peroxide value was somewhat fluctuated during heating period, and the maximum peroxide value in all samples was 13.3 meq/kg. TBA value was sharply increased for the first 10 hr. heating and slowed down thereafter for all samples but ERBO were intensely colored after the heat treatment. The TG ratio of the oils after 90 hr. heating was not different at $150^{\circ}C$ but ERBO was 2-7% higher ratio of TG than ARBO at $180^{\circ}C$. The oxidative stability of ARBO was twice higher than ERBO according to the result of active oxygen test.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.175-179
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• 1985

The alkali refined rice bran oil (ARBO) and the esterified rice bran oil (ERBO) with glycerol were analyzed for their physicochemical charateristics and the compositions. Specific gravity, refractive index and yellowness of ERBO was higher than ARBO but smoking point was 60-$80^{\circ}C$ higher than ERBO. The free fatty acid content was 0.05% a ARBO and 0.88-1.36% ERBO. The wax was not detected in ARBO but the soft and hard waxes were detected in ERBO. The lipids were composed of 98-99% neutral lipid, 0.2-0.5% glycolipid and 0.1-0.5% of phospholipid in all samples. The triglyceride content of neutral lipid was 96.3% ARBO and 93.0-94.1% ERBO, and its monoglyceride content was 0.11% ARBO and 0.39-0.69% ERBO. The major fatty acid composition of samples were 41-42% oleic, 36-40% linoleic and 17-18% of palmitic acid.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.803-807
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• 2009

Solid fats were esterified with solid phase of rice bran oil (S-RBO), palm stearin (PS), and conjugated linoleic acid (CLA) at 2 substrate mole ratios (S-RBO:PS:CLA of 1:1:2 and 1:3:4). The major fatty acids were palmitic, oleic, and CLA in 36 hr products. The solid fat content (SFC) of the 1:1:2 product was 12.8% while the SFC of 1:3:4 product was 45.1% at $20^{\circ}C$. The SFCs after $20^{\circ}C$ reduced when the reaction time increased from 1 to 36 hr, suggesting that the change of triacylglycerol species was augmented by extending reaction time.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.193-199
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• 1980

A series of tests were conducted on the reesterification of rice bran oil containing high free fatty acids (acid value=119.7) with theoretical equivalent of glycerol. Test results showed that reaction rate (in terms of decrease in acid value) was increased as the reaction temperature was increased regardless of the presence of the catalyst and reaction time (42.7, 21.5 and 10.0 at $170^{\circ}C,\;210^{\circ}C\;and\;250^{\circ}C$, respectively) and as the reaction time was increased regardless of the temperature and the presence of the catalyst (31.1 vs 18.3 for 3 hrs vs 6 hrs). The presence of the catalyst (0.2% tin chloride) also accelerated the rate regardless of the reaction temperature and time (36.9 vs 12.5). Analysis by column chromatography showed that content of triglyceride in the oil was increased to 72.9% and 61.1% from 10.4% and content of free fatty acids in the oil was decreased to 1.4% and 6.1% from 60.2%, when the degummed oil was esterified at $250^{\circ}C$ for 6 hrs in the presence of and in the absence of the catalyst, respectively. The results estimated from the iodine values indicate that polymer formation was not significant, when the oil was esterified for 6 hrs at temperatures up to $210^{\circ}C$. However, it was somewhat significant for the oil esterified at $250^{\circ}C$ for 6 hrs. The catalyst did not affect the polymer formation. Analysis by high performance liquid chromatography showed that oleic acid (42.5%), linoleic acid (29.0%) and palmitic acid (20.3%) were the major fatty acid components of the rice bran oil.