• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.38-45
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• 1993

Gel consistency data collected from various experiments in same location during 1988 to 1992 were analysed to clarify the degree of varietal and environmental variation in rice. Most of japonica and Tongil-type rice varieties were belonged to soft gel consistency, and average gel length of japonica rice was longer than that of Tongil-type varieties. Gel length of glutinous rice cultivars was extremely long, near 100mm. Year variation of gel consistency was recognized, but did not affect on varietal difference. Gel consistency of most rice varieties and pedigree lines tested varied slightly between different seeding dates or nitrogen levels, but gel length of two indica rice varieties were decreased with the later seeding dates or the higher nitrogen levels. Rice varieties belonged to extremely hard or extremely soft gel consistency showed less variation of gel length between different years, seeding dates or nitrogen levels compared with intermediate ones.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.179-184
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• 1976

Properties of starch from three rice varieties in Korea, Indica types Tongil, Yusin and a Japonica type Jinheung were investigated. 1) Gelatinization temperatures of Tongil, Yushin and Jinheung rice were $72^{\circ}C,\;70^{\circ}C\;and\;68{\sim}69^{\circ}C$ respectively. Gelatinization temperature of Indica variety was higher than that of Japonica variety. 2) Blue values of Tongil, Yusin and Jinheung rice starch were 0.40, 0.39 and 0.35 respectively, in which differences among rice varieties were small. 3) Color intensity of three varieties of rice starch with iodine gave rise to absorption maxima at $610{\sim}625\;nm$. 4) Amylose contents of Tongil, Yusin and Jinheung rice starch were 23.2%, 21.3% and 20.6% respectively, which were lower than those of other cereals. Amylose content of Indica variety was higher than that of Japonica variety. 5) Alkali numbers of Tongil, Yusin and Jinheung rice starchs were 7.0, 7.0 and 6.8, respectively. The differences were negligible among rice varieties. Those values were higher than that of glutinous rice starch.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.399-407
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• 2013

The purpose of this study was to evaluate the physicochemical characteristic of the cooked rice added with glutinous and non-glutinous sorghum. The sorghum cultivars were Sorghum bicolor L. Moench cv. Hwanggeumchal, Nampungchal (glutinous), and Donganme (nonglutinous), and rice cultivar was Ilpum rice. The cooking properties and pasting characteristics of cooking rice adding with sorghum according to varieties and different addition rates evaluated. The cooking properties and pasting characteristics had significant changes with the varieties and different addition rates of sorghum. With increased addition rates of sorghum, the pasting temperature, peak viscosity, trough viscosity, breakdown viscosity, and final viscosity were decreased. With increased addition rates of sorghum, the total polyphenol and flavonoid contents before and after cooked rice were increased. Total polyphenol contents of 30% addition rates before cooking rice with Hwanggeumchal, Nampungchal, and Donganme sorghum were 1,693.30, 1,890.98 and $2,386.11{\mu}g/g$ sample, whereas those after cooking rice with sorghum were 1,189.28, 1,190.42 and $1,397.87{\mu}g/g$ sample, respectively. The high level of DPPH radical scavenging activity before and after cooking rice with sorghum were 126.29 and 70.58 mg TE/100g sample in the Donganme in 30% addition rates. Also, ABTS radical scavenging activity was 135.56 and 83.12 mg TE/100g sample, respectively. The results of this study show that the addition of sorghum can make cooked rice improved antioxidant activity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.60-68
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• 2007

This study was perform to examine the feasibility of cooking processing using the rice added the 70% ethanol extract of pigmented rice bran layer. Four rice samples, including normal rice, glutinous rice, pigmented-normal rice, and pigmented-glutinous rice were compared the properties of physico-chemical, texture, and sensory evaluation. Pigmented rice varieties had a higher amylose content, but shorter length in glucose chains than non-pigmented rice varieties. The enthalpy for gelatinization was found to increase in pigmented rice, which need more energy for gelatinization of starch in cooking. The hydrolysis rate by glucoamylase in rice added pigmented bran extract was higher than pigmented rice. Rice with pigmented bran extract had higher glutamine content, but lower asparagine content and no difference in fatty acid composition, which affect palatability. Cooked rice added pigmented bran extract was less retrograded than pigmented rice during the storage period. Moreover, cooked rice added pigmented bran extract was more acceptable in sensory evaluation. Based on the results, the use of rice added pigmented bran extract instead of pigmented rice in grain processed food have advantageous effects in palatability of polished rice and phytochemicals of pigmented non-polished rice. This study will help develop new health-promoting rice products.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.1
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• pp.1-7
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• 2021

The processing of rice is one of the measures to expand the scope of rice use in response to the decrease in rice consumption. Since the main ingredient of rice processing is rice flour, "rice flour varieties" have been bred with the aim to improve the productivity and quality of rice flour. In order to study the variation in the ripening characteristics of rice flour varieties with respect to temperature, the average temperature after heading date was set at 28℃ (33/23℃), 22℃ (27/17℃), and 18℃ (23/13℃) inside the phytotron. We used Saenuri as non-glutinous rice variety, Seolgaeng as soft-type rice flour variety, and Baromi2 as powdered rice flour variety. At high temperatures (28℃), the grain weight of Baromi2 decreased by 21%. Its starch content also decreased by more than 10%, which was significantly lower than that of Saenuri and Seolgaeng. At low temperatures (18℃), the grain weight and starch content slightly increased or were similar in all varieties. An analysis of changes in the grain weight due to effective accumulated temperature through the sigmoid function showed that the velocity of grain-filling slowed significantly when Baromi2 was exposed to low temperature during the ripening stage compared to the other varieties. Therefore, the transplanting time of Baromi2 should be delayed to avoid high temperatures during the ripening stage. However, because the ripening period is not properly secured under low temperature conditions, grain filling may not be sufficient.

• The Korean Journal of Food And Nutrition
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• v.33 no.2
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• pp.204-209
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• 2020

We investigated the physicochemical properties of brown rice by cultivar to select cultivar suitable for making brown rice porridge. The moisture content of the brown rice ranged from 8.79~11.78% with the highest varieties being 'Geonyangmi'. The crude ash and crude lipid content ranged from 1.02~1.65% and 1.65~3.26%, while the rest were similar except for 'Daebo'. Crude protein also had the lowest 'Daebo' and generally glutinous rice showed higher crude protein content than common rice. The hardness showed that 'Seolgaeng' and 'Keunnun' were the lowest, and 'Haiami' was the highest. In the RVA analysis, the setback was in the range -80.61~22.44 and was low in the order of 'Wolbaek', 'Baekjinju'', and 'Dongjinchal'. As a result of water binding capacity (WBC) measurement, 'Sindongjin', 'Geonyang' and 'Samkwang', were high in common rice, and 'Dongjinchal' and 'Hwaseonchal' were high in glutinous rice. Generally, solubility and swelling power in common rice was found to be lower than in glutinous rice. As a result, 'Samkwang' is considered suitable for brown rice porridge production because of high WBC, breakdown, and low setback.

• Korean journal of food and cookery science
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• v.13 no.1
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• pp.64-69
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• 1997

The experiments of rice bread processing were carried out to compare the varietal difference in processing adaptability to rice bread between brown and milled rice flour, and to analyze the interrelations among chemical properties of rice grain and some characteristics relevant to rice bread processing and quality There was varietal difference in adaptability to rice bread processing in both brown and milled rice, but there was not significant adaptability difference between brown and milled rice flours to rice bread processing. However, there was remarkable adaptability difference between brown and milled rice flours to rice bread processing in some rice varieties. Three high-amylose rices AC 27, IR 44, Suweonjo showed high quality of milled rice bread among tested rice materials. Brown rice revealed better adaptability to rice bread processing compared with milled rice in all varieties except the above three varieties. Especially, the glutinous rice Hangangchalbyeo failed to normal formation of rice bread from milled rice flour, but it showed the successful formation of rice bread from brown rice flour. The interrelations among chemical components of rice grain and some characteristics relevant to rice bread processing and quality exhibited quite different tendency between brown and milled rices. In the case of rice bread processing by brown rice flour, the larger volume expansion of dough during fermentation made the more springy rice bread and the more moist rice bread showed the more soft and cohesive physical property. In the case of rice bread processing by milled rice flour, the lower protein of rice flour was closely associated with the more moistness of rice bread and the higher lipid led to the more uniformal air pore distribution, the smaller pore size and the lower springiness of rice bread. Also, the larger volume expansion of dough during fermentation made the better loaf formation and the larger pore size of rice bread. The better loaf formation of rice bread revealed the softer hardness and the lower chewiness, and the lower springiness was closely correlated with the more uniformal size distribution of air pore and the smaller pore size in rice bread.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.261-272
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• 2008

This study was conducted to provide the fundamental data based on the agronomic characteristics of domestic aroma rice, widely cultivated domestic rice and foreign aroma rice for breeding of functional aromatic rice. Among the 104 varieties, all of domestic aroma rice and widely cultivated rice varieties were headed, 24 of 84 varieties of foreign aroma rice were not headed. The average heading date of domestic aroma rice Japonica types of domestic rice was later as 136 day, and Tongil types of domestic aroma rice were faster as 122 day. The average culm length of Indica types of foreign aroma rice was longer as 130 cm, and Tongil types of were shorter as 74 cm. The average panicle length of domestic aroma rice and traditional rice were about 21 cm, and Indica types of foreign aroma rice were longer as 29.5 cm. The average 1,000 grain weight of Tongil types of domestic aroma rice and was not a difference with the domestic aroma rice and was more 2.5 g than the Indica types of foreign aroma rice. The average ratio of grain width and length of Indica types of foreign aroma rice were highest as 3.29 (W/L), and the domestic traditional rice was lowest as 1.7 (W/L). The average fertility rate of the domestic aroma rice, the widely cultivated domestic rice, and the Japonica types of foreign aroma rice were above 89.7%, but the Indica types of foreign and the Tongil types of domestic aroma rice were below 65.4%. The average germination rate of foreign aroma rice were above 83.7%, and domestic aroma rice were above 90.4%. The non-glutinous rice were 64 varieties (84.2%) of total 104 accessions of material rice and the waxy rice were 7 varieties (1%). In the domestic aroma rice, Hyangmi2ho and Aranghyangchalbyeo has a mild aroma grade. In the foreign aroma rice, 22 of 40 varieties of Indica types and 9 of 16 varieties of Japonica types has a lightly aroma grade. And 13 varieties of widely cultivated domestic rice has a non-aroma grade.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.31-37
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• 1993

To analyze and classify the varietal variation of alkali digestibility in detail, which is closely connected with the gelatinization temperature and physical characteristics of cooked rice, the patterns of alkali decomposition changed along the alkali concentration were investigated for thirty three Korean leading rice cultivars and new breeding lines(japonica : 25, Tongil-type:8) including five glutinous rice. Principal component analysis was used to condense the information and to classify rice materials according to decomposed reaction pattern at several levels of potassium hydroxide(KOH) concentration. Thirty three rice varieties were classified largely into four groups by the distribution on the plane of upper two principal component scores which contained above 92% of total informations. Group I was consisted of one variety, Dobongbyeo, which owned almost same strong resistance to alkali digestion at the range of 0.8% to 1.6% KOH solutions. Group II included three japonica and Tongil-type glutinous rice varieties, which revealed medium alkali digestion value(ADV) at 1.4% KOH solution and intermediate change in ADV from 0.8% to 1.6% KOH solutions. Most of Tongil-type and early-maturity japonica rice, which exhibited medium-high ADV at 1.4% of KOH concentration and large ADV difference between low and high alkali solutions, were contained in Group III. Group N included most of medium or medium-late-maturity japonica, which showed high ADV at 1.4% KOH and medium or intermediate-high ADV change between low and high alkali solutions. The 1st principal component indicated the average index of ADV through 0.8-1.6% KOH solutions and the 2nd principal component pointed out the factor related with ADV difference between low and high alkali solutions or regression coefficients of ADV change along with the KOH concentrations.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.144-152
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• 1977

The physiochemical properties of eight different cultivars or newly bred lines of glutionous rice were investigated and obtained following results; (1) The gelatinizing temperature, blue value and alkali number of starch separated from the sample cultivars or lines were similar to those of starch from conventional cultivar Olchal. The expansive power of three newly bred lines were somewhat weaker than that of starch from conventional cultivar, but the expansive power of other four lines were similar to that of conventional cultivar. (2) pH of cooked rice of the ten sample cultivars or breeding lines showed no discernible differences rangeing from 6.54 to 6.60. (3) The degree of gelatinization of cooked rice of newly bred lines were rather lower than that of conventional ones, but the degree of their retrogradation were somewhat higher than that of conventional cultivars. (4) In order to improve the palatability of cooked rice of Tongil (common rice), glutinous rice were mixed in different rate. The results showed that a mix ratio of six per cent glutinous rice was most favourable. The acceptability of common Tongil rice was improved when it was cooked with four to six per cent of glutinous rice mixed, and it showed no significant difference from that of Akibare alone cooked rice. Also no difference was noticed among newly bred glutinous lines in the acceptability when they cooked with common Tongil rice mixed. (5) Injolmi, Yaksik, Misitgaru, Twipap and Yugwa were prepared from glutinous rice of sample cultivars and or breeding lines to study their characteristics in processing and their acceptability. The results indicated that the acceptability score of newly bred lines were lower than that of conventional cultivar in cases of Twipap and Yugwa, but in cases of Injolmi, Yaksik and Misitgaru, identical score was obtained from both of newly bred lines and conventional cultivars.