• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.1102-1105
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• 2006

The effect of heat treatments on in vitro starch hydrolysis of proso millet, sorghum, Job's tears, and buckwheat by pancreatic ${\alpha}-amylase$ was investigated. Grain samples were tested raw, boiled in water, or steamed/roasted. Starch content of the grains varied from 59.5% in Job's tears to 65.5% in proso millet, and amylose content varied from 5.3% in Job's tears to 36.3% in buckwheat. The in vitro starch hydrolysis of raw and heat-treated grains continuously increased during 60 min of hydrolysis. The starch hydrolysis (%) of raw grains after 60 min incubation was in the order of buckwheat (5.7%), proso millet (33.0%), Job's tears (51.2%), and sorghum (57.6%). Grains treated with steaming/roasting appeared to have higher starch hydrolysis rates than those with boiling except proso millet. Hydrolysis rates of buckwheat with a high amylose content appeared to be lower, compared to proso millet, sorghum, and Job's tears containing low amylose contents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.637-645
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• 1991

Physicochemical factors affecting cooking and eating quality of rice and their mechanisms were investigated. The stickiness of cooked rice was negatively correlated with amylose content(r=0.58, p<0.05) and protein content(r=-0.72, p<0.01), but not affected by crude fat content of rice. The ultrastructure of cooked rice grain showed the progressive gelatinization of starch from the periphery toward the center of the endosperm as water and heat energy diffused into. The rate of water diffusion appears to be dependent on the cell arrangement in the endosperm and the protein content of milled rice. Once water and heat reach the starch granules, the rate of in situ gelatinization of starches appears to be dependent on their own gelatinization temperature range and amylose content. Protein acts as a barrier for the swelling of starch and water diffusion in two ways : 1) by encasing starch granules in the starchy endosperm, and 2) by forming a barrier between the subaleurone layer and the starchy endosperm. Therefore, the separation and fragmentation of the outermost layers of the endosperm occurred more easily in the low-protein content rices, and was associated with increases of solids lost in cooking-water at 95$^{\circ}C$ and stickiness of cooked rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.5
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• pp.288-293
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• 2000

Two rice cultivars (Oryza sativa L.), Hwa-seongbyeo of Japonica type and Taebackbyeo of Indica/Japonica type, were cultivated with hydroponic culture to examine nitrogen effects on the growth responses, contents and utilizations of carbohydrates, and the ripening velocity of grains with three different N levels. Plant height and tiller number were clearly increased to 80 ppm N level compared to 40 ppm N level and then they were slightly decreased in N level of 120 ppm. Higher dry weights were appeared with 80 ppm N level than did with other N levels, showing statistically differences in both cultivars and N levels, while dry weight of roots was heavier with decreasing the N levels. Therefore, T/R ratios were not significantly different among N levels, although there was statistically differences between rice cultivars. After the flowering stage, higher water-soluble carbohydrate (WSC) and water-insoluble carbohydrate (WISC) were contained in stem compared with other parts, showing that WISC of sheath and stem, unlike WSC, was significantly different among N levels. Starch of grain, WISC, was remarkedly increased from 3.0% at just after the flowering to 52.0% and 75.0% at 15 and 30 day after the flowering, respectively, showing that lower N application had faster accumulation of starch in rice grains. N would affect the contents of carbohydrates of each tissue, and starch accumulation in rice grains.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.2
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• pp.187-193
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• 2014

As a result of the cost of grains, the replacement of grains by co-products (i.e. DDGS) in feedlot diets is a common practice. This change produces diets that contain a lower amount of starch and greater amount of fibre. Hypothetically, combining feed grade urea (U) with slow release urea (Optigen) in this type of diet should elicit a better synchrony between starch (high-rate of digestion) and fibre (low-rate of digestion) promoting a better microbial protein synthesis and ruminal digestion with increasing the digestible energy of the diet. Four cannulated Holstein steers ($213{\pm}4$ kg) were used in a $4{\times}4$ Latin square design to examine the combination of Optigen and U in a finishing diet containing different starch:acid detergent fibre ratios (S:F) on the characteristics of digestive function. Three S:F ratios (3.0, 4.5, and 6.0) were tested using a combination of U (0.80%) and Optigen (1.0%). Additionally, a treatment of 4.5 S:F ratio with urea (0.80% in ration) as the sole source of non-protein nitrogen was used to compare the effect of urea combination at same S:F ratio. The S:F ratio of the diet was manipulated by replacing the corn grain by dried distillers grain with solubles and roughage. Urea combination did not affect ruminal pH. The S:F ratio did not affect ruminal pH at 0 and 2 h post-feeding but, at 4 and 6 h, the ruminal pH decreased as the S:F ratio increased (linear, p<0.05). Ruminal digestion of OM, starch and feed N were not affected by urea combination or S:F ratio. The urea combination did not affect ADF ruminal digestion. ADF ruminal digestion decreased linearly (p = 0.02) as the S:F ratio increased. Compared to the urea treatment (p<0.05) and within the urea combination treatment (quadratic, p<0.01), the flow of microbial nitrogen (MN) to the small intestine and ruminal microbial efficiency were greater for the urea combination at a S:F ratio of 4.5. Irrespective of the S:F ratio, the urea combination improved (2.8%, p = 0.02) postruminal N digestion. As S:F ratio increased, OM digestion increased, but ADF total tract digestion decreased. The combination of urea at 4.5 S:F improved (2%, p = 0.04) the digestible energy (DE) more than expected. Combining urea and Optigen resulted in positive effects on the MN flow and DE of the diet, but apparently these advantages are observed only when there is a certain proportion of starch:ADF in the diet.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.6
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• pp.513-523
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• 1993

Varietal difference in structural and physical characteristics of rice starch and interrelationships between these starch properties and the physicochemical components of rice grains were investigated for twenty four rice varieties, which were considerably different in amylose content, gelatinization temperature and gel consistency, to obtain the basic informations for diversifying the utility of rice grains and for developing various rice cultivars adaptable to rice food processing. Wave length of maximum absorbance for blue color reaction of starch-I$_2$ complex was 520nm for glutinous rice and 560～600nm for nonglutinous rice. The higher amylose rice showed the longer wave length but there was considerable difference of the wave length among rice materials with similar amylose content. Varietal difference in frequency distribution of debranched starch molecules by isoamylase hydrolysis was largest in amylose fraction, the longest fraction(Fr. I), and was next bigger in intermediate fraction(Int.Fr.) and the ratio between short and long glucose chain of amylopectin fraction(Fr. III /Fr. II). The Fr. III / Fr II ratio was higher in glutinous rice than in nonglutinous one but it was considerably different among nonglutinous rice varieties without any connection with amylose content. The lower alkali digestible rice showed the longer half-hydrolysis time in acid solution. Both soft and hard gel rice varieties in gel consistency test revealed significant varietal difference of 50% acid hydrolysis time. The harder rice in gel consistency exhibited the less frequency of short branch fraction of amylopectin (Fr. III) and the higher amylose content. Twenty four rice varieties were cleary classified by upper two principal components contracted from structural or physical traits of rice starch and some physicochemical properties of rice grain by principal component analysis. The 1st and 2nd principal components can be characterized to components related with amylose and amylopectin structure respectively.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.27-36
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• 1990

Injeolmi is a kind of rice cake made from glutionusrice grains by steaming and pounding much into dough. The way of making Injeolmis has an important effect on the characteristics of Injeolmis; whether the glutinous rice is Japonica or Japonica/Indica, and whether it is steamed in rice grain, or in rice powder. The characteristics of Injeolmi were investigated through sensory evaluation and Instron Universal testing machine. The results were as follows; 1. Injeolmi which was steamed in glutinous rice was more chewier than powder Injeolmi after 48 hours. 2. In the case of changing ${\beta}$-starch to ${\alpha}$-starch by reheating. Injeolmi with microwave oven, the result was same as above investigation in color, appearance, and chewiness. But in hardness grain Injeolmi became tenderer. 3. Instron measurement of texture indicated that there were significant differences in hardness. This result was the same as that by the sensory evaluation. 4. The preference for Injeolmi was increased when it was made of high moisture contented glutinous rice. japonica had more moisture than J/Indica.

• Journal of Plant Biotechnology
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• v.40 no.2
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• pp.88-101
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• 2013

Eating quality of rice attracts more and more attention from rice-eating consumers in the recent years. Thus, improvement of eating quality of cooked rice has become one of the most important breeding goals in japonica rice. Here, the generation of transgenic japonica rice with improved eating quality and grain yield are reported. Overexpression of OsSbe1 gene encoding rice starch branching enzyme 1 was driven by 35S promoter. Eleven independent homozygous $T_3$ transgenic lines were characterized and had shown higher palatability (71.2 ~ 72.6) than wild type Gopum (70.4). Moreover, transgenic rice lines showed an increase in 1000-grain weight and number of spikelets per panicle compared with the wild type. The yield of milled rice was 562.8 ~ 596.7 kg/10a in eight $T_3$ lines, but 542.1 kg/10a in wild type. Gene expression analyses in mRNA transcription and enzyme activity levels suggest that improved eating quality is due to the up-regulation of OsSbe1 gene.

• Korean journal of food and cookery science
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• v.16 no.4
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• pp.342-351
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• 2000

This study aimed for exploring the best recipe of Sangjabyung to increase its utility value and to develop traditional Korean rice cake industry for next generation. The best recipe was determined after several tests such as sensory evaluation and mechanical measurements for texture, moisture content, and colorimetry. The samples prepared with 5% of acorn starch with honey showed the best scores in sensory evaluation for color and flavor, 5% of acorn powder with sugar for grain, 15% of acorn powder with sugar for moistness and chewiness, 15% of starch with honey for sweetness, and non-glutinous rice flour mixed with 10% of acorn powder and sugar for overall quality. Every item except for flavor was significantly different from that of control (P<0.05). The highest score for springiness was obtained from the samples prepared with 10% of acorn starch with sugar, cohesiveness with 5% of acorn starch with sugar, chewiness with 15% of acorn starch with honey, gumminess with 15% of acorn starch with honey, adhesiveness with 5% of acorn starch with honey, and hardness with 15% of acorn starch with honey. All items were significantly different from that of control (P<0.05). The overall quality of sensory evaluation was correlated with moistness(P<0.05), springiness, cohesiveness(P<0.01), and adhesiveness(P<0.01) in mechanical test. Moisture contents of rice flour, acorn starch, and acorn powder were 32.93%, 8.52%, and 13.26%, respectively. The desirable moisture content in Sangiabyung was 44.11% in the case of using rice flour with acorn starch or 44.33% for rice flour with acorn powder. As a result of colorimetry, the best L, a, and b values were obtained from the rice cakes with 5% acorn starch and oligosaccharides, with 15% of acorn powder and sugar, and with 15% of acorn starch with oligosaccharides, respectively. Overall. the most desirable recipe for Sangjabyung was determined as rice flour 315 g, acorn starch or acorn powder 35 g, sugar 60 g, salt 3.5 g, and water 130 ml.

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.51-51
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• 2023

Global warming has significant effects on the growth and development of wheat and can cause a reduction in grain yield and quality. Grain quality is a major factor determining the end-use quality of flour and a reduction in quality can result economic losses. Therefore, it is necessary to study the physiological characteristic of wheat to understand its response to temperature elevation, which can aid in the development of strategies to mitigate the negative effects of high temperature and sustain wheat production. This study investigated the effects of elevated temperature on grain characteristics and quality during the grain filling period of two Korean bread wheat cultivars Baekkang and Jokyoung. These two bread wheat cultivars were subjected to an increasing temperature conditions regime; T0 (control), T1 (T0+1℃), T2 (T0+2℃) and T3 (T0+3℃). The results showed that high temperature, particularly in T3 condition, caused a significant decrease in the number of grains per spike and grain yield compared to the T0 condition. The physical properties, such as grain weight and hardness, as well as chemical properties, such as starch, protein, gluten content and SDSS, which affect the quality of wheat, were changed by high temperature during the grain filling period. The grain weight and hardness increased, while the grain size not affected by high temperature. On the other hand, amylose content decreased, whereas protein, gluten content and SDSS increased in T3 condition. In this study, high temperature within 3℃ of the optimal growth temperature of wheat, quantity properties decreased while quality-related prosperities increased. To better understand the how this affects the grain's morphology and quality, further molecular and physiological studies are necessary.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.2
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• pp.95-105
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• 1973

Sink (grain)-filling rates of IR667 line (Suwon 213 and 214) and local leading varieties (Jinheung and Paldal) were investigated in relation to sink-source ratio, sink-source distance, forms of photosynthates, and weather factors. The results are as follows. 1. IR667 line have higher maximum filling rate (g. grain/day. ear) and shorter duration to reach maximum filling rate than local varieties. The curve pattern of sink-filling rate was high and steep type in IR667 line and low and broad type in local varieties. 2. Weather factors seem to give little effect on the curve pattern of sink-filling rate. 3. The functional sink-source distance (actual sink-source distance multiplied by the contribution rate of leaf for grain production) was shorter in upper leaves (flag and 2nd leaf) for IR667 line, the upper leaf-dependent type in grain production, and was longer in lower leaves (3rd and 4th) for local varieties, the lower leaf-dependent type. Specially short first internode from top may contribute to the upper leaf depencency of IR667 line. 4. According to free sugar-starch ratio (sugar/starch) in the culm and leaf sheath IR667 line could be classified as the high sugar type and the local varieties as the high starch type. The ratio of transportable form (sugar) to non transportable photosynthate (starch) seems to relate with sink-filling rate. And high sugar type is expected to have higher efficiency for grain production in view of energy balance. 5. A hypothesis that the higher in the uniformity within the series of productive structure the more efficient in grain production is proposed and discussed in relation to productivity. 6. According to the pattern of percent nutrient retention of each leaf blade IR667 showed the central retention type and Jinheung showed the apical retention type and each retention type appears to be a cause of each canopy conservation pattern. 7. From the content and percent distribution of nutrient in various organ IR667 could be classified as the leaf sheath dominant type and Jinheung as the leaf blade dominant type. 8. The fact that the greater the percent translocation of nutrient into grain the greater the percent nutrient retention in leaf blade was held between nitrogen and phosphorus within a variety and between varieties within a nutrient (N, P or K).