• Korean journal of food and cookery science
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• v.22 no.2 s.92
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• pp.147-157
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• 2006

To improve the properties of non-waxy rice flours for baking, soaked-wet milled rice flour (SWRF) was adjusted moisture content (MC) to 30 and 50 % and heated at 50 and $70^{\circ}C$ in a shaking water bath for 6 and 18 hrs, respectively. Moisture-heat treated rice flours were investigated with regard to particle size distribution, and morphological, physicochemical and pasting properties for comparing dry and wet milled flours. The particle size of rice flour treated with 30% MC was distributed between $4-20{\mu}m\;and\;100-200{\mu}m$, like SWRF. The particles above $200{\mu}m$ in the flour were produced at higher heating temperature. By SEM, starch granules were found in the rice flours treated with 30% MC, who whereas aggregated starch granules were shown in the flours treated with 50% MC. Moisture-heat treatment using higher MC and heating temperature decreased the lightness and increased the yellowness of non-waxy rice flours. Water binding capacity of 30% moisture treated rice flour was similar to that of SWRF. In the same moisture treated rice flour, swelling power was higher, but solubility was lower at $50^{\circ}C$ than at $70^{\circ}C$. The initial pasting temperature by RVA increased after moisture-heat treatment. The peak viscosity of moisture-heat treated rice flour was higher for 30% moisture than that of the others. The rice flour treated with 30% MC and heated at $50^{\circ}C$ showed low setback and increased stability for retrogradation.

• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.307-313
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• 1981

The components of several kinds of Sokokju (old Korean cleared rice wine) prerared in the laboratory by two steps mashing and commercial Yakju (Korean cleared rice wine) were evaluated. The Sokokju mashed with half steamed waxy rice in tile primary fermentation yielded higher contents of alcobol and extract. Especially considerable amount of pyruvate was contained in it. The commercial Yakju sample contained abundantly tartarate and citrate while dominant organic acids in the fermented mashes of Sokokju were lactate, fumarate and succinate. The taste characteristics of the Sokokju brewed with half steamed waxy rice were most acceptable to the sensory panel.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.219-219
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• 2022

Granule-bound starch synthase I (GBSSI), encoded by the waxy gene, is responsible for the accumulation of amylose during the development of starch granules in rice endosperm. Despite many findings on waxy alleles, the genetic diversity and evolutionary studies are still not fully explored regarding their functional effects. Comprehensive evolutionary analyses were performed to investigate the genetic variations and relatedness of the GBSSI gene in 374 rice accessions composed of 54 wild accessions and 320 bred cultivars (temperate japonica, tropical japonica, indica, aus, aromatic, and admixture). GBSS1 coding regions were analyzed from a VCF file retrieved from whole-genome resequencing data, and eight haplotypes were identified in the GBSSI coding region of 320 bred cultivars. The genetic diversity indices revealed the most negative Tajima's D value in the tropical-japonica, followed by the aus and temperate-japonica, while Tajima's D values in indica were positive, indicating balancing selection. Diversity reduction was noticed in temperate japonica (0.0003) compared to the highest one (wild, 0.0044), illustrating their higher genetic differentiation by F_ST-value (0.604). The most positive Tajima's D value was observed in indica (0.5224), indicating the GBSSI gene domestication signature under balancing selection. In contrast, the lowest and negative Tajima's D value was found in tropical japonica (-0.5291), which might have experienced a positive selection and purified due to the excess of rare alleles. Overall, our study offers insights into haplotype diversity and evolutionary fingerprints of GBSSI. It ako provides genomic information to increase the starch content of cooked rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1047-1052
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• 2001

The pigment content in meju fermented by a Monascus species with different materials was studied. The relations between growth of M. pilosus and pigment production were positive and the correlation coefficient associated with this relationship was determined to be : r = 0.9879. Pigments produced by M. purpureus and M. pilosus were composed of 9 and 8 bands, respectively. One kind of them was yellowish, whereas the others were reddish. Total pigment levels in rice meju fermented by M. purpureus and M. pilosus were 335.25 and 1428.90$\mu\textrm{g}$/g, respectively. Pigment levels in the mejus fermented at 3$0^{\circ}C$ showed higher than those at 20 and 4$0^{\circ}C$. The order of pigment content in meju was polished rice > germinated brown rice > wheat > brown rice > waxy brown rice > germinated waxy brown rice. Pigment production by M. pilosus was higher than that of M. purpureus. Pigment content in rice meju prepared by adding 10% seed culture was highest, and pigment content of granulated rice was higher than that of powdered rice. Pigment production was not desirable in soybean meju fermented by seed culture, whereas the pigment levels in meju by adding 10% powdered rice and 10% powdered rice seed meju increased by 23.0 ~75.0 $\mu\textrm{g}$/g.

• Korean journal of food and cookery science
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• v.33 no.2
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• pp.198-208
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• 2017

Purpose: To improve the quality of basic gluten-free rice bread composed of white rice flour, salt, sugar, yeast, skim milk powder, olive oil, and water, the effects of transglutaminase (TGase), whey protein (WP), propylene glycol alginate (PGA), and hydroxypropylmethylcelluose (HPMC) were investigated. Methods: TGase, WP, PGA, and HPMC were added to rice flour cumulatively. The pasting properties of rice flour blends as well as volume, shape, color value, textural properties and sensory evaluation of basic rice bread (RB1) RB1+TGase (RB2), RB1+TGase+WP (RB3), RB1+TGase+WP+PGA (RB4), and RB1+TGase+WP+PGA+HPMC (RB5) were compared. Results: Consistency of rice batter increased upon addition of TGase, WP and PGA, and RB3 and RB4 had higher specific volumes than others. PGA improved volume, crumb air cell uniformity, and resilience but lowered elasticity and moistness of RB. HPMC increased, hardness, moistness and softness, and slightly reduced volume. Conclusion: Therefore, it is suggested that hydrocolloids, PGA and HPMC may be necessary to improve volume, crumb structure, textural properties and overall eating quality of gluten-free rice bread.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.384-389
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• 1997

Attempts were made to improve gelatinization, saccharification and panfrying processes for mass production of Nochi, a kind of traditional Korean rice cake. Gelatinization of waxy rice powder with 20-55% of moisture content were completed within a minute at 120$^{\circ}C$ or above by using the extrusion cooker. Among enzymes tested for liquefaction and saccharification of the gelatinized rice, in place of malt, BAN (0.53%)+${\beta}$-amlyase (4.27%) was the most suitable enzymes for the production of Nochi. Panfrying process of Nochi was drastically shortened by heating Nochi dough for 1 minute in a microwave oven and subsequently panfrying at 150$^{\circ}C$ for 7 minutes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.8
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• pp.1076-1083
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• 2009

The physicochemical properties of rice flour produced by 3 different grinding methods using various steeping times (3, 6, 9, and 12 hrs) were investigated. Roller mill gave coarse rice flour; the pin mill, intermediate flour; and mixed when both (roller & pin mills) were used. With the increase of steeping times, the rice flours became finer and the contents of crude protein, crude fat and crude ash decreased. Damaged starch was noticeably high in rice flour by roller & pin mills compared to those by roller or pin mills alone. Amylose contents, solubility and swelling power increased as the steeping times increased. Water binding capacity was the highest in roller & pin mills, followed by pin mill. In scanning electron microscope (SEM), pin mill showed distribution of separated fine particles of rice flours. The physicochemical properties of rice flours showed many differences by steeping times of rice and grinding methods. With sufficient steeping times, the rice flours obtained from pin mill were relatively fine having less damaged starch.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.593-600
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• 2014

Normal rice starch (NRS) possesses high gelling and retrogradation tendencies, with poor freeze-thaw stability. This study investigated the effects of partial replacement of waxy rice starch (WRS) with gums on the pasting and viscoelastic properties as well as the freeze-thaw stability of the WRS paste. Xanthan gum (XAT), locust bean gum (LBG), and their mixtures were individually mixed with WRS at a ratio of 1:19 (w/w). WRS-gum mixtures were pasted using a rapid visco-analyzer at 5% total solid content, and analyzed with respect to the pasting and viscoelastic characteristics, and freeze-thaw stability. Pasting properties of WRS were retarded in pasting temperature and enhanced in pasting viscosity (although peak viscosity was varied) by partial replacement with gum and gum mixtures. Storage moduli of WRS-XAT:LBG pastes became similar to those of NRS paste with increasing angular frequency from 1 to 10 rad/s. Finally, WRS-XAT and WRS-XAT:LBG possessed more enhanced freeze-thaw stability than NRS.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.84-91
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• 2009

Rice consumption per capta, in South Korea, has been decreased dramatically, owing to the changes of living patterns. Because of not only the major energy source of Korean people but also major income source of Korean farmers, diversifying end-use-quality of rice has been demanded. To the context, 'Suweon 472', a high yielding and early mature japonica line and released as 'Namilbyeo' to framers in 2002, was treated with a chemical mutagen, Sodium Azide to find endosperm mutant types. A total of nine endosperm mutat lines, including five waxy, one dull, two floury, and one white core type, were identified from the 3,542 mutatagen treated lines. Amylose contents, iodine reaction, disintegration in alkali solution, gelatinization in urea solution and amylogram properties of those nine endosperm mutant lines were evaluated to address the possibility as new genetic materials for diversifying rice quality of Korean japonica cultivars. All embryo mutants were clearly differentiated from their wild type, 'Suweon 472', in terms of physic-chemical properties evaluated. The endosperm mutant lines would be very useful in expanding untiliztation of rice through opening new rice markets of processed foods from Korean japonica rice.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.299-305
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• 2009

A new six-rowed naked barley cultivar "Jinjuchal" with high whiteness after cooking and high $\beta$-glucan content was developed from the cross between 'Jinmichapssalbori' with high winter hardiness, lodging tolerance, grain whiteness and pearling yield, and 'Suwon 333' with waxy endosperm by the Honam Agricultural Research Institute (HARI), NICS, RDA in 2007. An elite line, SB962002G-B-B-B-84-4 was selected in 2002 and designated as 'Iksan 79' It showed good agronomic performance in the regional yield trials (RYT) from 2005 to 2007 and was released with the name of "Jinjuchal" possessing high whiteness and low proanthocyanidin waxy endosperm. The average heading and maturing dates of "Jinjuchal" were April 27 and June 1 in paddy field, which were same and one day later than those of the check cultivar 'Saechalssalbori' respectively. The new cultivar, "Jinjuchal" had 81 cm of culm length that was 1cm longer than that of 'Saechalssalbori' and 4.9 cm of spike length. It showed 673 spikes per $m^2$, 56 grains per spike, 27.0 g of 1,000-grain weight, and 752 g of test weight. "Jinjuchal" showed stronger hardiness and better resistance to powdery mildew and BaYMV (Barley yellow mosaic virus) than those of the check cultivar, 'Saechalssalbori' It showed higher $\beta$-glucan content(8.4%) and water absorption rate than those of the check cultivar, 'Saechalssalbori' Its average yield of the pearled grain in the regional yield trial was 3.79 MT/ha in upland, and 3.73 MT/ha in paddy field, which were 1% lower and 3% higher than those of the check cultivar, respectively. Total phenol and proanthocyanidin contents were 4.2 and 0.2 mg/g, respectively. This cultivar is suitable for the area of the daily minimum temperature above $-6^{\circ}C$ in January in Korean peninsula.