• Korean journal of food and cookery science
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• v.23 no.3 s.99
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• pp.314-320
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• 2007

The objective of this study was to investigate the effect of grain size on the physicochemical properties of rice porridge. Here, the grain size of the rice was classified as whole grain, half grain, and flour by traditional Korean cooking methods. The viscosity of the rice flour porridge was highest for the among the three different grain size porridges. In the amylographs, the increase in viscosity for the whole grain porridge was higher than that of the rice flour porridge during cooling. The soluble solid and reducing sugar contents of the rice porridges increased according to the rice grain size, while the blue value decreased. The SDI (starch digestion index) increased according to the rice grain size. The RDS (rapidly digestible starch) was highest while the SDS (slowly digestible starch) the lowest in the rice flour porridge. The morphologies of the rice porridges were examined by SEM and showed a smoother surface and more exudated gelatinized granules in the rice flour than in the whole grain rice porridge. In conclusion, rice porridges made from the smallest possible grain size such as flour may be helpful for people with weaker digestive systems such as infants, the elderly, and hospital patients.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.249-259
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• 2009

Puroindoline alleles, grain characteristics, milling performances and physical properties of flour of 22 Korean wheat cultivars were evaluated to determine the influence of puroindolines genotypes on grain and flour characteristics and to provide useful information for improving milling and end-use quality in Korean wheat breeding programs. Nine Korean wheat cultivars carried with Pina-D1a/Pinb-D1a, 11 cultivars had Pina-D1a/Pinb-D1b and 2 cultivars were Pina-D1b/Pinb-D1a. Korean wheats carrying with Pina-D1a/Pinb-D1a genotypes showed lower test weight and thousand kernel weight, area and roundness of grain and hardness index in grain characteristics, lower flour yield and higher proportion of break flour in milling performances and lower average particle size of flour, ash and damaged starch content, water retention capacity, yellowness-blueness and higher lightness of flour than wheats with Pina-D1a/Pinb-D1b or Pina-D1b/Pina-D1a genotypes. Pina-D1a/Pinb-D1b genotypes showed lower 1000-kernel weight, grain area, higher average of particle size of flour, higher ash and damaged starch content than Pina-D1b/Pina-D1a genotypes. There was no difference in hardness index of grain, milling performances, flour color between Pina-D1a/Pinb-D1b and Pina-D1b/Pina-D1a genotypes. These results could present the information to improve milling quality and physical properties of flour in Korean wheat breeding programs.

• Korean journal of food and cookery science
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• v.31 no.3
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• pp.264-279
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• 2015

The principal objective of this study was to evaluate the effects of the addition of sourdough to various grain flours in bread, specifically, in regards to the physicochemical characteristics of bread dough, sensory evaluation, and bread storage. As the incubation time of sourdough increased, the total titratable acidity increased. Viable yeast counts of sourdough increased consistently until the third day, while lactic acid bacteria counts increased until the second day. The weight of breads containing sourdough made with rye flour, strong flour, and Korean wheat flour were higher than that of the control. However, the height, volume, and specific volume of control were higher than those of the groups with sourdough made with various grain flours. The pH of breads containing sourdough was lower than that of the control, while the total titratable acidity and moisture content were higher than those of the control. In analyzing the visible mold colony during the five days of storage at $30^{\circ}C$, mold growth in breads containing sourdough made of Korean wheat flour, barely flour, and rye flour was retarded. In the color measurement, the L values of the control and bread containing sourdough made with barley flour were higher than that of the other groups after five days. The a value of bread containing sourdough made of rye flour was higher, and the b values of breads containing sourdough made of Korean wheat flour, barley flour and rye flour were higher than those of the other groups after five days. The hardness of breads containing sourdough increased as storage time increased, where as breads containing sourdough made of Korean wheat flour, Korean whole wheat flour, and rye flour revealed no significant differences with control group. Sensory evaluation scores in terms of after swallowing, taste, and overall preference of bread containing sourdough made of Korean wheat flour was higher than those of the control group.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.966-978
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• 1993

A power operated 90.5 hp electric motor) grain flour separator was designed and developed for separation of grain (wheat, corn, chickpea and soybean) flour into various fractions based on the size of the particles of the product. The separator agitating mechanism, feed control, cylindrical separator unit and an eccentric mechanism. The machine was tested for wheat ( variety ; Sujata) flour separation into four fractions, viz ; semolina, Gr-I and II, flour (coarse) and white (fine) flour. Wheat samples (6.8% m.c., db) were first pearled by CIAE pearler for 15.8% bran removal . The pearled wheat grains were then milled for semolina by a burre mill. The product and machine characteristics were determined at different capacities varying from 24 kg/h to 143 kg/h. It was found that 76 kg/h capacity gave reasonably best results in terms of purity and recovery of semolina vis-a-vis the market product. The energy requirement of the machine at no-load was found to be 230 W and at load c nditions, it varied between 36.3-6.4 KJ per kg of fead seperation. The macine could be used by small flour millers small/medium size traders and retailers and other processors for making available various flour products of different particle size in the market for ready use of the consumers.

• Journal of the Korean Home Economics Association
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• v.23 no.3
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• pp.63-73
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• 1985

This study was conducted to investigate the effects of fermentation time and the proportion of wheat flour to rice flour on Jeung-Pyun's texture. Textural characteristics were examined through sensory Evaluation and Instron Universal testing machine. The properties examined through sensory evaluation were grain, softness, sourness, chewiness and overall quality. Wigh Instron, hardness, cohesivenessm elasticity, gumminess and chewiness were measured. RESULTS : 1. Sensory evaluation data indicated that Jeung-Pyun containing 25% wheat flour and fermented 2 hrs were obtained higher scores than any other Jeug-Pyuns in the grain, softness and overall quality. 2. pHs of Jeung-pyundough and Jeung-Pyun containing 100% rice flour were lower than pHs of those with wheat flour added. 3. Volume of Jeung-Pyun increased as the proportion of wheat flour to rice flour and the length of fermentation time increased. 4. Instron measurement indicated that the hardness of Jeung-Pyun with 50% wheat flour added and 2hrs fermentation time was higher than of others.

• Food Science and Industry
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• v.50 no.2
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• pp.86-97
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• 2017

The major food grains in Korea are rice and barley. The wheat was supplied from USA after World War II in 1945 and it changed the eating habits for Korean diet. The role of barley as a food grain has been diminished and that of wheat has been acknowledged; the consumption per capita per year of wheat is over the half of that of rice which is the staple grain in Korea. This article is a brief review on the background of wheat becoming the important grain in Korean diet and the following developmental story of flour mills. Emphasis was given to the statistics on flour mills industry.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.1
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• pp.13-20
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• 2002

Bread baking parameters and relationships between bread baking properties and flour characteristics were evaluated for two years, 1997 and 1998, and at two locations, Suwon and Deokso, with Korean winter wheat cultivars and lines. Among the bread baking parameters, lightness of crumb grain showed differences between years. No significant differences were found in dough mixing time, bread loaf volume, crumb grain score or firmness. Keumkangmil, Suwon 278 and Tapdongmil showed higher bread loaf volume, good structure of crumb grain and softer crumb firmness. However, compared to commercial flours for baking, cultivar means averaged over years and locations of nineteen Korean winter wheats showed poor bread baking quality because of low protein content and unsuitable protein quality. Protein content and flour swelling volume showed better relationships with the bread baking parameters than other flour characteristics. Friabilin-absence lines showed softer crumb firmness than those of friabilin-presence lines.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.207-213
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• 1999

Thirty-eight glutinous rice varieties were classified into nine groups on the scatter diagram by the upper two principal components (56% contribution to the total information) based on eleven physicochemical characteristics including the viscograms and physical properties of cooked rice. The first principal component was the factor mainly associated with the viscogram characteristics of rice flour emulsion and the second was the factor chiefly related to the physical properties of cooked rice and water absorbability of rice grain. Indica glutinous rices were clearly distinguished from japonica ones by the first principal component score. Javanica glutinous rices were widely distributed on the intermediate zone between indica and japonica or on several japonica rice groups. Significant positive or negative correlations were found among water absorption rates of rice grain, physical properties of cooked rice, and viscogram characteristics of rice flour. Especially in japonica glutinous rices, the breakdown and setback viscosities of rice flour were closely associated with the alkali digestion value of milled rice and the stickiness of cooked rice. The frequency ratio of short glucose chains (A-chain) to intermediate glucose chains (B-chain), the ratio of B- chains to long glucose chains (C-chain) and the relative frequency of A- or B-chain fractions representing the amylopection structure of rice starch was closely associated with the breakdown and setback viscosities of rice flour.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.979-983
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• 1993

A power operated (0.5 hp electric motor) grain flour separator was designed and developed for separation of grain (wheat, corn, chickpea and soybean) flour it no various fractions based on the size of the particles of the product. The separator is made of mild steel and consists of a hopper, power driven agitating mechanism, feed control , cylindrical separator unit and an eccentric mechanism. The machine was tested for wheat (variety : Subjata) flour separation into four fraction, viz : semolina ; Gr-I and II, flour (coarse) and white (fine) flour. Wheat samples (6.8% m.c., db) were first pearled by CIAE pearler for 15.8% bran removal . The product and machine characteristics were determined at different capacities varying from 24 kg/h to 143 kg/h. It was found that 76 kg/h capacity gave reasonably best results in terms of purity and recovery of semolina vis-a-vis the market product. The energy requirement of the machine at no-load was found to be 230 w and at load conditio s, it varied between 36.3-6.4kj per kg of feed separation. The machine could be used by small flour millers, small/medium size traders and retailers and other processors for making available various flour products of different particle size in the market for ready use fo the consumers.