• Preventive Nutrition and Food Science
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• v.4 no.4
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• pp.231-235
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• 1999

Three black rices(Suwon 415, Iksan 427 and Sanghaehyanghyeolla) harvested in Korea were examined in their pasting characteristics, and minor nutrients(vitamins and minerals) in comparison to those of a brown rice (Dongjinbyo), whereas Iksan 427 and Sanghaehyanghyeolla were waxy rices(0.4 and 0.6%, respectively). Iksan 427 and Sanghaehyanghyeolla showed similar viscosity pattern with significantly low pasting temperatures and viscosity. Brown rice showed higher pasting viscosity and pasting temperature than black rices, and its viscosity pattern was similar to Suwon 415. Brown rice and Suwon 415 displayed higher hardness but lower adhesiveness of their gels. Black rices contained more non-carbohydrate components and dietary fiber than brown rice. From the amino acid analysis, black rices contained more acid amino acids (aspartic and glutamic acids) than brown rice. Among the black rices, Suwon 415 had the highest content of total essential amino acids(4.3%). Black rices also contained higher amounts of vitamin B complexes (thiamin, riboflavin and niacin) and minerals(K, Mg and Ca) than brown rice. Sanghaehyanghyeolla showed an exceptionally high amount of Ca (12mg%).

• Applied Chemistry for Engineering
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• v.18 no.1
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• pp.41-47
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• 2007

Crude copper phthalocyanine (Cupc) was synthesized by Wyler process, then grounded using various methods such as acid pasting, kneader, attritor and SC-mill. Particle size, shape and crystalline structure were compared and evaluated after particle size reductions. Cupcs prepared by acid pasting and kneader methods that are excellent manufacturing processes in industry were used as our standards. Particle properties of Cupcs prepared either by attritor or by SC-mill were compared with particle size analyzer, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Particle size analyzer and SEM were used to analyze the variation of particle sizes of Cupc with milling time. Particle size was initially decreased up to the 90 min of milling time, thereafter it reversely began to increase in case of SC-mill. Cupc obtained from dry milling with attritor displayed strong cohesion so that particle size was not possible to determine with particle size analyzer. However, the optimum milling time was indirectly approximated from the analysis of XRD peak intensity.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.755-760
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• 2008

The aim of this study was to produce resistant starch preparations from acid-modified com starches prepared at various hydrolysis levels (0.5-4.0 hr). Effect of autoclaving cycles on resistant starch (RS) formation was investigated. Molecular weight distribution, pasting and functional properties of acid-modified com starches were determined. For RS formation native and acid-modified starch samples were gelatinized and autoclaved (1 or 2 cycles). While native and acid-modified starches did not contain any RS, the levels increased to 9.0-13.5% as a result of storage at $95^{\circ}C$ after first autoclaving cycle. Second autoclaving cycle together with storage at $95^{\circ}C$ brought final RS contents of the samples incubated at 4 and $95^{\circ}C$ after the first cycle to comparable level. As acid modification level increased, the amount of high molecular weight fractions decreased, resulting in significant decreases in viscosities (p<0.05). The samples produced in this study had low emulsion stability and capacity values.

• Textile Coloration and Finishing
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• v.15 no.1
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• pp.8-14
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• 2003

The effect of pasting agent on the defibrillation of Tencel fabric was investigated. It was evaluated by the weigth loss of fabric when the fabric was treated with cellulase containing various kinds of pasting agents. The surface appearance of Tencel fabric was checked by SEM. Under the treatment condition without pasting agent, the weight loss of fabric was high at pH 5.0 and $60^\circ{C}$. This means that the cellulase activity was high at this condition. By increasing the concentration of carboxymethyl cellulose(CMC), the weight loss of fabric was decreased monotonously. This tendency was not appeared in other pasting agents. CMC is synthesized by the reaction of chloroacetic acid and cellulose. The glucose units may be remained after the reaction. So, it was considered that the degradation of glucose unit in Tencel was decreased, because cellulase had to attack both Tencel and CMC.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.149-153
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• 2005

Composition and pasting properties of endosperms of one common buckwheat (CB) and two tartary buckwheats (TB) grown in China were investigated. No differences were observed in proximate composition and amino acid content between CB and TB. Content of rutin in TB was 22-fold higher than that of CB. Among minerals, iron, calcium, and magnesium contents were higher in TB than CB, whereas zinc, manganese, and phosphorus contents were similar, Pasting properties measured with Rapid visco Analyzer revealed TB-2 cultivar had highest peak viscosity, trough, and breakdown, followed by TB-1 and CB. Setback of TB was about 2.2-fold greater than that of CB. Significant differences in color were observed between CB and TB, and among TB cultivars.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.396-402
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• 2020

In order to investigate the changes in the quality attributes during the storage of dry-milled rice flour, two flour samples were obtained from two rice varieties (Hangaru (HG), Samkwang (SK)). These samples were stored at 4℃ and room temperature, respectively, and we analyzed the initial rice flour moisture content and chemical properties. The changes in the rice flour pasting and quality properties during storage were measured for 12 months. Our results showed that HG exhibited better pasting properties than SK, while the fat acidity of HG rapidly increased at room temperature, resulting in short shelf-life. However, the low-temperature (4℃) storage of dry-milled rice flour could reduce the change in the free fatty acid values of both samples. Therefore, low-temperature storage seems to contribute not only to an increased rice flour shelf-life by reducing the fatty acid value changes but also to a reduction in the changes in pasting properties.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1145-1149
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• 2009

Physicochemical properties of native and acid-modified Job's tears (Coix lachryma-jobi L.) starches were investigated. Starch extracted from Job's tears was treated with 2.2 N hydrochloric acid for different length of time (3, 6, 12, and 18 hr). The hydrolysis pattern of starches with the acid proceeded rapidly up to 12 hr and then the approached constant values. The swelling power of acid-modified starches measured at all temperatures was lower than that of its native counterparts and the water solubility index increased as temperature and hydrolysis time increased. Rapid visco analyzer viscograms of acid-modified starches demonstrated a very low viscosity as compared with that of native starch. However, Xray diffraction did not show any significant alteration in the crystallinity after acid-modification.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.207-211
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• 2008

In order to understand the difference in rice eating quality, two rice varieties having different eating qualities were examined from the correlation between palatability score (Toyo value) and components of lipid in rice endosperm. We also analyzed the relationship between lipid properties and physicochemical characteristics of milled rice. Major fatty acids of milled rice starch-lipids, known to exist as inclusion complexes with amylose in starch granules, were palmitic (38.25% in Gopum and 39.75% in Palgong) and linoleic aicds (33.13% in Gopum and 31.93% in Palgong). In addition, the unsaturated fatty acid contents of rice endosperm showed a significant relationship with palatability. Plant sterols in two rice samples were identified, Gopumbyeo of good eating quality had high contents of squlaene and cycloartenol and similar contents of campesterol, stigmasterol and sitosterol. There were significant differences in pasting properties of rice flours and starches between the two cultivars. These results suggested that rice lipids impact on pasting properties after cooking, subsequently relating to palatability.

• Journal of Applied Biological Chemistry
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• v.49 no.3
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• pp.95-100
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• 2006

Brown rice with a giant embryo (GE) was observed on the quality parameters of the enlargement of embryo, nutritional components, and physical properties, in comparison to normal embryo brown rice (NE). Also, the effects of germination on the quality parameters were examined. GE embryo was approximately 2.68 times larger than of NE rice. Total free sugars were significantly higher in GE rice (71.96 vs. 41.17 mg/100 g), and germinated rice increased in fructose, but decreased in sucrose and maltose. No significant difference in mineral contents was found in GE and NE rice and their germinated rice, whereas a significant increment was observed on reducing sugars and gamma-amino butyric acid (GABA) contents in GE rice. The lower water absorption index (WAI) of GE rice resulted in relatively lower pasting viscosity, whereas the increased WSI in germinated rice might be attributable to the significant increment of soluble components in GE rice.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.218-228
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• 2015

In this study, the physicochemical characteristics of rice sourdough fermented with Omija extract were investigated. Rice sourdough was made with a 3 stage fermentation process. pH & total titratable acidity, numbers of yeast and lactic acid bacteria, and dough expansion rate were measured. In addition, an RVA was employed to study the pasting properties of rice sourdough. There was a significant (p<0.05) change in both the pH of rice sourdough, which decreased from 5.08 to 3.98, and total titratable acidity, which increased from 0.20 to 0.57 (0.1N NaOH mL), as fermentation time increased. The amount of yeast and lactic acid bacteria significantly increased from 6.73 to 7.65 log CFU/g, 6.93 to 7.65 log CFU/g, respectively(p<0.05). The expansion rate of rice sourdough fermented with Omija extract was higher than rice sourdough fermented without Omija extract. The initial pasting temperatures of rice sourdough fermented with Omija extract were decreased from $91.3^{\circ}C$ to 85.6. The final viscosity and setbacks decreased as fermentation time increased. These results suggest that Omija extract has a beneficial effect on increasing the expansion rate of rice sourdough as a substitute for wheat flour.