• Nutritional Sciences
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• v.3 no.1
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• pp.3-10
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• 2000

The present study was aimed at investigating the nutritional and physiological significance of rice bran as a source of dietary fiber as compared to pectin and wheat bran. The parameters for comparison included hypertrophy and morphology of intestines, stool weights and villus marker enzyme activity. For 6 weeks, 10 Sprague Dawley male rats were given one of six experimental diets: 1% cellulose control (CC), 5% pectin (P5), 5% rice bran(RB5), 10% rice bran(RB10), 5% wheat bran (WB5) or 10% wheat bran (WB10) based on the level of dietary fiber. Among experimental groups, food efficiency ratio and body weight gain was comparable. RB10 increased cecal and colonic tissue weights and content weights of cecum and colon as much as P5 did. Stool weight was positiviely correlated with colonic tissue weight (r=0.727, P<0.001), with colonic content weight(r=0.647, P<0.001). Small intestine length increased most in the P5 group, followed by the RB10 group. The scanning electron micrograph of jejunal villi from rice bran groups showed a leaf-shaped, smooth and regular pattern, whereas that of CC group produced a rather long shape. The wheat bran groups showed an irregular leafshaped pattern, and the pectin group typically produced leaf-shaped villi with surface damage. The activities of villus marker enzymes (maltase and sucrase) were higher in the bran-fed rats than in the control or pectin-fed rats. The results indicate than not only dietary fiber amounts but also fiber sources are closely related to the physiology and morphology of the large and small intestines in rats. Rice bran exerted effects on fecal output and trophic effects on the intestines similar to those of pectin.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.210-218
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• 2018

This study was conducted to examine the influence of different transplanting dates on rice quality and starch properties (morphology and pasting properties) of rice varieties that may be used for the production of rice flour. Three rice flour varieties, 'Seolgaeng', 'Hangaru', and 'Milyang317', were transplanted on May 20, May 30, June 10, and June 20. The peak viscosity decreased with a delay in the transplanting date. However, the amylose content increased with a delay in the transplanting date, whereas that of protein decreased. Amylopectin short-branch chain content increased in the rice varieties that were transplanted on May 30. The morphology of the starch granule of the varieties was determined by SEM. No apparent external difference in the starch granules was observed for the different transplanting dates. These results indicate that the transplanting date influenced the amylopectin structure and pasting properties, which led to changes in the physicochemical characteristics of rice starch.

• Korean journal of food and cookery science
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• v.33 no.3
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• pp.307-315
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• 2017

Purpose: To develop nano-sized starch particles for application as dietary fiber sources in liquid food system, the morphology and thermal properties of acid hydrolyzed rice starches with different amylose contents were evaluated. Methods: Rice starches purified from three Korean cultivars, including Goami, Hopyeong, and Hwaseonchal, were hydrolyzed with 2.2 N HCl solution in a $35^{\circ}C$ shaking water bath (100 rpm) for 7, 10 and 15 days. Results: Acid hydrolysis rates of rice starches increased with increasing hydrolysis duration, and rates for Goami, Hopyeong, and Hwaseonchal were 28.74-38.50%, 38.96-49.53%, and 40.24-48.88%, respectively. The granular size of acid hydrolyzed starches decreased to 122.4-479.9 nm, whereas granular aggregation increased with increasing hydrolysis duration. In particular, waxy rice starch of Hwaseonchal was composed of many tiny granules without aggregates. Gelatinization temperature and temperature range increased with increasing hydrolysis duration. All starches showed A type crystallinity using an x-ray diffractometer, regardless of acid hydrolysis. Conclusion: It is suggested that nanoparticles could be prepared by acid hydrolysis of rice starches, and waxy rice starch is the most preferred source for application.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.255-263
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• 2011

Projected increases in atmospheric $CO_2$ concentration ([$CO_2$]) and temperature ($T_a$) have the potential to alter in rice growth and yield. However, little is known about whether $T_a$ warming with elevated [$CO_2$] modify plant architecture. To better understand the vertical profiles of leaf area index (LAI) and the flag leaf morphology of rice grown under elevated $T_a$ and [$CO_2$], we conducted a temperature gradient field chamber (TGC) experiment at Gwangju, Korea. Rice (Oryza sativa L. cv. Dongjin1ho) was grown at two [$CO_2$] [386 (ambient) vs 592 ppmV (elevated)] and three $T_a$ regimes [26.8 ($\approx$ambient), 28.1 and $29.8^{\circ}C$] in six independent field TGCs. While elevated $T_a$ did not alter total LAI, elevated [$CO_2$] tended to reduce (c. 6.6%) the LAI. At a given canopy layer, the LAI was affected neither by elevated [$CO_2$] nor by elevated $T_a$, allocating the largest LAI in the middle part of the canopy. However, the fraction of LAI distributed in a higher and in a lower layer was strongly affected by elevated $T_a$; on average, the LAI distributed in the 75-90 cm (and 45-60 cm) layer of total LAI was 9.4% (and 35.0%), 18.8% (25.9%) and 18.6% (29.2%) in ambient $T_a$, $1.3^{\circ}C$ and $3.0^{\circ}C$ above ambient $T_a$, respectively. Most of the parameters related to flag leaf morphology was negated with elevated [$CO_2$]; there were about 12%, 5%, 7.5%, 15% and 21% decreases in length (L), width (W), L:W ratio, area and mass of the flag leaf, respectively, at elevated [$CO_2$]. However, the negative effect of elevated [$CO_2$] was offset to some extent by $T_a$ warming. All modifications observed were directly or indirectly associated with either stimulated leaf expansion or crop phenology under $T_a$ warming with elevated [$CO_2$]. We conclude that plant architecture and flag leaf morphology of rice can be modified both by $T_a$ warming and elevated [$CO_2$] via altering crop phenology and the extent of leaf expansion.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.5
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• pp.539-550
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• 1996

Experiment was conducted to study the effect of sources of dietary fiber on the intestinal morphology of geese. Sixty white Roman geese of two-week-old were divided randomly into six groups and were fed with isoenergetic and isonitrogenous diets which contain alfalfa meal, barley hull, rice hull, purified cellulose, lignin, or pectin as the major dietary source of fiber. Different sources of dietary fiber significantly influenced the villi height and the crypt depth in the duodenum, and the villi height and the muscle layer thickness in the ileum (p < 0.05). The duodenal villus in the geese that fed diets with alfalfa meal, rice hull or pectin supplemented were significantly longest ($968.5{\mu}m$), whereas the lignin group was significantly shortest villus and deepest crypt depth (p < 0.05). The thicknesses of the ileal and caecal muscle layer were significantly thicker in the geese fed with cellulose supplemented diets than in those fed with the other treatment diets. The caecum of the barley bran fed geese possessed significantly longest villi and the most thick muscle layers (p < 0.05). From scanning electronic microscopic observation, the leafy and plate-like in the duodenal villi morphology of geese represented a more effective nutrient absorption in the small intestine. The morphology of ileal villi in geese was similar from herbivorous rabbit and from the African Green monkey.

• Journal of Plant Biology
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• v.37 no.1
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• pp.53-67
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• 1994

The opal phytolith types in Oryza sativa L. were examined with light and scanning electron microscope, and we suggested the standard tenninoligies based on original cells of the phytoliths in situ. The distinctive fonus of opal phytoliths were observed in all plant parts such as leaf blade, leaf sheath, culm, root, glume, lemma, and palea. The phytolith fonus originated from long cell, short cell, and dennal appendages were different from part to part. The opal phytoliths derived from the long cells showed the most various form: twelve types were identified based on side wall shape. The results showed that the leaf blade did include almost all types of opal phytolith observed in the other parts of rice.f rice.

• Food Science and Preservation
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• v.8 no.2
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• pp.181-186
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• 2001

The objective of this study is to determine the effect of soy protein isolate (SPI) film coating on the color, firmness, viscosity and weight loss of Rice Cake stored at 15, 20 and $25^{\circ}C$ (RH 50%) for 30 days. Raw materials mixed with SPI and cocoa powder (10:0, 7:3, 5:5, 3:7, w/w) were prepared. After adding sugar and shortening to raw materials, the mixture were refined to 25 micron of particle size. Coating of Rice Cake were carried out at $65^{\circ}C$. SPI coated Rice Cake had higher internal and external firmness comparing to the control at $25^{\circ}C$. SPI coated Rice Cake showed smooth surface morphology and had 0.71-1.01 mm of thickness. SPI coated Rice Cake showed less weight loss for 30 days compared to controls. SPI coating solution was successfully coated on Rice Cake and extended shelf-life over 15 days at room temperature.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.1
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• pp.11-18
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• 2001

The saccharification and sensory characteristics of Sikhe, Korean traditional beverage of saccharified rice, made from thirteen glutinous rice varieties and one of non-glutinous rice named I1pum were examined. During saccharification, Shinsunchalbyeo, Whasunchalbyeo, Yukdononhrimna 1 and Hangangchalbyeo showed the highest sweetness determined by refractometer. Yukdononhrimna 1 was good for the morphology and texture of cooked rice kernel during saccharification. There was interrelationship between contents of released reducing sugar and sweetness determined by refractometer during preparation of Sikhe. The overall acceptability determined by sensory evaluation of Sikhe made from Yukdonongrimna 1, was slightly higher than that of Sikhe made from Ilpum, the non-glutionous rice variety. Yukdononhrimna 1 was considered to the most suitable varieties of Sikhe.

• Korean journal of food and cookery science
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• v.16 no.1
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• pp.91-97
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• 2000

The cooking properties of imported rice (Thai and Chinese rice, harvested in 1998) were compared with those of domestic rice(Chuchung byeo, harvested in 1998 and 1997). The morphology, general composition, color value, RVA viscosities, cooking properties, texture and sensory properties of raw or cooked rice were measured. Thai rice showed lower water absorption rate than others, however its amylose content and gelatinization temperature were higher. While the cooked Thai rice showed the least preference due to its hard and nonsticky properties, Korean rice harvested in 1998 showed the greatest cooking quality in stickiness and softness. Although Chinese rice was inferior to Korean rice harvested in 1998, there were no significant difference between Chinese rice harvested in 1998 and Korean rice harvested in 1997.

• Journal of Powder Materials
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• v.2 no.2
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• pp.135-141
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• 1995

As the first step of study on fabrication of ceramic powders from phytoliths in rice, especially in rice husks, pulverization method of rice husks and the properties of milled rice husks were investigated. Impact methods, such as ball milling, were not meaningful for pulverizing elastic and thin fabric structure of rice husks. The most effective one was cutting method. In the present work, a rotating knife cutting method was applied to pulverizing rice husks. A 40-mesh screen was inserted under the rotating knives. The most portion of the milled powder was found in -50/+100 mesh section. Morphology of the milled rice husks revealed that the husks larger than 70 mesh were flake-like shape, at -70/+100 mesh section relatively equi-axed shape, at -170/+325 mesh section rod-like shape, and below 325 mesh section dust-like shape. Tap density of raw rice husks was about 0.1 $g/cm^3$, while those of milled rice husks were over $0.4 g/cm^3$. This meant that, for a given volume of reactor, raw material charge can be increased more that 4 times when using milled rice husks than unmilled one. True densities of unmilled and milled rice husks were higher than $1.4 g/cm^3$, and increased with decreasing milled sizes.