Compositional changes of rice germ oils prepared at different roasting temperatures (160-180°C) and times (5-15 min) from rice germ were evaluated and compared with those of unroasted rice germ oil. The color development and phosphorus content of oils increased significantly as roasting temperature and time increased, whereas the FA compositions of rice germ oils did not change with roasting temperature and time. Four phospholipid classes, i.e., PE, PI, PA and PC, were identified. PE had the lowest stability under roasting conditions. There were no significant differences in γ-oryzanol levels of rice germ oils prepared at different roasting temperatures and times. Four tocopherol isomers (α-, β-, γ-, and δ-tocopherol) and three tocotrienol isomers (α-, γ-, and δ-tocotrienol) were identified, but no β-tocotrienol was detectable. The content of α-and γ-tocopherol in rice germ oil gradually increased as roasting temperature and time increased.

The objectives of this research were to characterize capsaicin-loaded nanoemulsions stabilized with natural biopolymer such as alginate and chitosan for use as a functional ingredient delivery system. The biopolymer nanoemulsion was prepared using self-assembly emulsification methods, and the capsaicin included oleoresin capsicum as the core material in the nanoemulsion. The particle sizes of the double-layer nanoemulsions prepared with alginate (AN) and chitosan (CN) were 20 nm or lower. The triple-layer nanoemulsion, which was prepared by complexation with chitosan and alginate (CAN), was successfully prepared with particle sizes on the nanoscale through the electrostatic interactions between the carboxylic groups and amine groups of the biopolymers. The Zeta potential value, which is an indicator of the overall stability and physicochemical properties of the nanoemulsion, of AN and CN were significantly higher than SN and CAN (p<0.01).In conclusion, the double-layer nanoemulsions incorporated with alginate and chitosan can be expected to improve the stability of nanoemulsion. In addition, this system holds promise for use in the production of functional foods containing functional ingredients.

HHPE used for red ginseng processing contributes to enhanced extraction efficiencies of functional materials such as ginsenosides through cell structure modification.

Aroma-active compounds from a beeflike process flavor, produced by extrusion of enzyme-hydrolyzed vegetable protein (E-HVP), were analyzed using aroma extract dilution analysis. The number of aroma-active compounds and the aroma intensity were increased by the addition of aroma precursors prior to extrusion. The most intense compound was 2-methyl-3-furanthiol having a cooked rice/vitamin-like/meaty aroma note. Several sulfur-containing furans, such as 2-methyl-3-(methylthio)furan, 2-methyl-3-(methyldithio)furan, and bis(2-methylfuryl)disulfide, were detected with high flavor dilution (FD) factors. Some pyrazines, such as 2-ethyl-3,5-dimethylpyrazine, 2,6-diethylpyrazine, and 3,5-diethyl-2-methylpyrazine, also had high FD factors. It is hypothesized that sulfur-containing amino acids and thiamin were important precursors in aroma formation in process flavor from E-HVP.

Apple pomace (AP), a fibrous by-product of apple juice processing, was solubilized by a twin-screw extruder. AP was extruded under I4 digerent operating conditions, where the process variables are controlled in the following ranges: screw speed, 250-350 rpm; feed rate, 30-40 kg/h; moisture, 20-30%. Water soluble index (WSI) increased linearly with specific mechanical energy (SME). Soluble dietary fiber of extruded AP also increased with SME, which in turn decreased the content of insoluble dietary fiber (IDF). As a result, total dietary fiber mF) remained nearly unchanged. Water holding capacily (WHC) remained nearly constant at low SME, but markedly deceased at high SME due to disintegration of cell wall. Gel filtration of WSP exhibited the structural fragmentation of cell wall by extrusion: the higher SME, the higherfragmentation of SME. Ion exchange chromatography of WSPdemonstrated that increasing SME resulted in increasing the extractability offree neutralpolysaccharides from the cell wall of AP. It was also found that the degradation of AP cell wall by extrusion preferentially occurred at the arabinogalactan sidechains of pectins.

Twin-screw extruder was employed to disintegrate apple pomace (AP) to facilitate production of apple pectins by hot water extraction. AP was extruded under different conditions of screw speed, 250-350 rpm; feed rate, 30-40 kg/h; moisture, 20-30%. The yield of water soluble polysaccharides (WSP) increased with increasing specific mechanical energy (SME), but intrinsic viscosity decreased with increasing SME. Considering both the WSP yield (g/dL) and intrinsic viscosity (dL/ g), a dimensionless term, product yield ∞ intrinsic viscosity (Y[ ]), was an objective function for optimizing conditions for the solubilization of AP polysaccharides. Y[ ] of pectins in extruded WSP ranged 0.59-1.34, while acid extracted WSP had Y[ ] of 1.12. Extruded WSP with Y[ ] comparable to acid extraction was obtained in the SME ranges of 110-170 kWh/h.

Degummed rice bran oil was deacidified by caustic, solvent and steam refining processes. The steam refining process was optimized through a series of experiments with varying refining times (1–5 hr), temperatures (220–280 C) and amounts of steam (4–20%), at a pressure of 4 mmHg. The most significant factors affecting the degree of deacidification were the refining temperature and amount of steam. The correlation coefficient between quadratic equation obtained and experimental results was 0.96. Acid value and color of steam refined oil were not as good as those of caustic refined oil, but steam refining showed better retention of natural antioxidants than caustic or solvent refining. Steam refining is preferred for deacidification of rice bran oil because of reduced neutral oil loss and elimination of soap production.The important criteria in selecting a deacidification process are known to be the degree of deacidification, neutral oil loss, effect on bleaching and production of soapstock (2,8–10). In comparing caustic refining, solvent refining and steam refining, caustic refining of degummed rice bran oil resulted in satisfactory acid values and color but showed the worst result in neutral oil loss and produced large amounts of soapstock. Solvent refining was not shown to be efficient because of poor deacidification, high losses of neutral oil and darkening of color. Steam refining also was less effective than caustic refining in deacidification and bleaching. However, the degree of deacidification could be improved by development of a process to remove all the free fatty acids (8), and the color problem could be eliminated by including a preliminary bleaching step before steam distillation (10). The application of steam refining to rice bran oil will result in many advantages such as reduced neutral oil loss, no production of soap, and the production of high purity, industrial fatty acids.

Tocol levels in the milling fractions of rice, barley, corn, wheat, and soybeans were analyzed by HPLC with a fluorescence detector. Among all milling fractions tested in this study, rice germ had the highest total tocol levels. In the four milling fractions of barley, except pearling flour, all eight tocol isomers were detected, and they were more uniformly distributed than in any other cereal grains measured in this study. The total tocol and α-tocopherol levels of wheat germ were significantly (P < 0.05) higher than the other wheat milling fractions. A significantly (P < 0.05) higher proportion of γ-tocopherol was obtained from corn germ (71.5%) and endosperm (50.3%) than from corn hulls. Only four tocol isomers (α-, β-, γ-, and δ-tocopherol) were detected in soybean milling fractions; no tocotrienol isomers were detected. The δ-tocopherol level of soybean endosperm, although minor, was significantly higher than those in milling fractions of other cereal grains in this study.Paper no. J10476 in JAOCS 80, 585-589 (June 2003).a Results (mg/kg of fraction) are expressed on a dry weight basis, and means within columns followed by the same letter are not significantly different P < 0.05). Values in parentheses are the percent distribution of each tocol. For abbreviations see Table 1.