• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.2
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• pp.187-195
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• 2008

Polyphenol oxidase (PPO) is implicated in discoloration of white salted noodles and other wheat based foods. PPO activity was evaluated to determine the effect on discoloration of noodle dough sheets prepared from 25 Korean wheat flours during storage and to screen experimental lines with low PPO activity in 52 Korean wheats. PPO activity was assayed with whole-seed and performed with L-dihydroxyphenylalanine (L-DOPA) as substrates. Absorbance by L-DOPA assay of 25 Korean wheats was from 0.285 to 1.368 at 475 nm. PPO activity was significantly related with grain characteristics, including 1000-kernel weight and grain colors. In flour characteristics, PPO activity positively correlated with ash and protein content (r = 0.658, P < 0.001 and r = 0.424, P < 0.05, respectively) and negatively correlated with $L^*$ value of flour (r = 0.412, P < 0.05). In the changes of color of noodle dough sheet, $L^*$ and $b^*$ values consistently decreased and $a^*$ value increased during storage. PPO activity negatively correlated with $L^*$ value of noodle dough sheet during storage (r = 0.566, P < 0.01 at 2 hr, r = 0.547, P < 0.01 at 24 hr, and r = 0.509, P < 0.01 at 48 hr). But, no significant relationship was found in between PPO activity, $a^*$ and $b^*$ values during storage. The 52 Korean wheat lines examined in this study were divided into 3 different groups, low (< 0.500), medium (0.501-0.999) and high level (> 1.000), on the basis of the level of PPO activity. Twenty two Korean wheat lines showed low level of PPO activity and Suwon 252, 277 and 280 showed lower PPO activity (< 0.200) than others.

• Journal of the Korean Society of Food Culture
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• v.29 no.5
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• pp.437-443
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• 2014

The quality characteristics of noodles made from domestic Korean wheat flour added with 0, 1, 3, 5% cactus Chounnyuncho (Opuntia humifusa) powder were investigated. The water absorption and peak time of dough, as determined by farinography, increased with higher cactus powder content. Stability and elasticity of dough decreased as fermentation proceeded. Cooking characteristics of noodles made from dough such as weight, water absorption, and volume decreased with higher cactus powder content. The turbidity of cooked water increased significantly with 5% cactus powder content. For color test, L-value decreased while a-value and b-value increased with higher cactus powder content. In texture analyses, hardness, adhesiveness, springiness, cohesiveness, and gumminess increased with higher cactus powder content. In the sensory test, noodles containing 3% cactus powder were the most preferred.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.749-753
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• 2002

The effects of green tea powder (GTP) on the rheological properties of dough and gelatinization characteristics were evaluated by farinograph, extensograph, amylograph and DSC. The flours used were high strength flour (HF: 12.5% protein) and blend of 50% high strength flour and 50% low strength flour (HLF: 10.5% protein). As the amount of GTP increased, water absorption, development time and weakness of the dough decreased for both flours, but dough stability increased only for HLF; the extension of the dough decreased but the resistance to extension increased. The pasting temperature increased and maximum viscosity decreased. On the other hand, with the addition of green tea extract to the wheat starch, transition onset temperature, transition peak temper-ature and enthalpy decreased, demonstrating that catechins in green tea facilitate the starch crystal melting.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.314-320
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• 2002

When the soybean milk residue flour were added to the respective wheat flour at level of 5%, 10% and 15% the possibility of bread making were studied. Vital gluten was added to the soybean milk residue portion of a 10% composite flour at levels of 3%, 6% and 9% to improve bread quality. And test was baking properties of soybean milk residue composite flour and sensory evaluation of composite breads. Major components of soybean milk residue flour were crude protein, 22.0%; crude lipid, 13.2%; carbohydrate, 54.3%; and dietary fiber, 27.2%. When 5%, 10% and 15% soybean milk residue flour was blended with wheat flour, water absorption, development time and bread weight were increased, and volume of dough and loaf was decreased. But improved bread-making properties by adding gluten. Color of crumb got darker as the percentage of soybean milk residue flour increased, got brighter when gluten was added. Texture of bread increased in chewiness and hardness as the percentage soybean milk residue flour increased but not different in cohesiveness. The use of vital gluten showed influence to springiness, chewiness and hardness. The sensory evaluation showed that 5% soybean milk residue-wheat bread was similar to bread made from wheat flour in overall acceptability. And the bread made by miting gluten were better than 10% soybean milk residue-wheat bread in overall acceptability.

• Korean journal of food and cookery science
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• v.31 no.5
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• pp.551-556
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• 2015

Iksan370 is a long-spike wheat developed by the Rural Development Administration yielding excellent features components such as cold resistance, disease resistance, and viviparous germination. The physicochemical and material properties of the raw wheat and milled flour of Iksan370 were analyzed to derive its appropriate uses. The raw wheat of Iksan370 showed high contents of ash and proteins at 1.71% and 13.7%, respectively. Its test weight of 763.0 g/L was similar to those of other varieties and its 1,000 kernel weight was high at 45.38 g. The milled flour of Iksan370 had an ash content of 0.45%, which corresponds with a class 1 flour, and its protein content is 12.18%, corresponding with strong flour. The damaged starch was 5.41%, which was lower than that of other varieties. The average grain size was $70.67{\mu}m$ and the grain distribution was at the level of a typical hard wheat. In the farinogram, the water absorption was 58.63%, which corresponded to the level of medium flour. The development time was 7.00 minutes, which was significantly lower than those of Jokyung and Keumkang. The degree of softening was 67.00 BU, similar to those of Yunbaek and Baekjoong. Among the physico-chemical characteristics, the high protein content and typical hard wheat grain distribution of Iksan370 were similar to those of strong wheat, usually used for bread making. However, in the farinogram, the dough development time was short and the degree of softening was high. As a result, Iksan370 was expected to have poor breadmaking properties and a small volume of the final bread product due to insufficient dough durability. On the other hand, Iksan370 showed the highest maximum gelatinization viscosity at 864.00 BU. Therefore, Iksan370 is expected to show glutinous texture when used for noodles and its flour appears to be appropriate for frying powders as well.

• 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.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.456-462
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• 2009

In comparison to processed wheat flour products, there is no established method for determining the water absorption of rye flour. The aim of this study was to work out a method using the Planetary mixer P 600 for the determination of water absorption (WA) and the rheological properties in rye dough made from rye flours of 4 different types (I-IV). In the correlation analysis showed that WA had positive correlation with ash, beginning of gelatinization, $125-160{\mu}m$ particles, sedimentation values at 20 and 25 min, bread yield, pH, and total titratable acidity, but had negative correlation with initial viscosity, gelatinization maximum, viscosities on swelling at 25, 28, and $31^{\circ}C$. The WA determined by the Planetary mixer P 600 agreed well with the experimental baking tests.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.296-296
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• 2022

This study was investigated to compare the milling and physicochemical characteristics of six Korean wheat cultivars (Keumkang, KK; Jokyung, JK; Goso, GS; Joongmo2008, JM; Baekkang, BK; Saekeumkang, SKK) and five foreign wheat classes (Australian standard white wheat, ASW; Australian hard, AH; US northern spring, NS; US hard red winter, HRW; Soft wheat, SW). Korea and foreign wheat grains were milled using a Buhler MLU-202. Flour moisture, ash, protein, gluten, sedimentation, particle size, solvent retention capacity (SRC) and dough properties of flour were analyzed. Results showed that the hard wheats had a greater total flour yield and reduction fraction yield than the soft wheats regardless of the country. However, there were in the milling characteristics between the US and Korean soft wheats. GS, a soft wheat in Korea, had the lowest flour yield (59.6%) and the highest bran fraction yield (21.4%). The particle sizes of flour by milling fraction were B1>B2>B3 for the largest, and the R1〈R2〈R3 for the smallest. Particle size, ash, protein contents and the values of lactic acid SRC showed highly correlated with flour yield. The gluten-performance-index (GPI) is the ratio of the lactic acid SRC value to the sum of sodium carbonate and sucrose SRC values, and it has been used as a quality indicator for overall performance potential of flour. GPI values differed depending on the wheat variety or class, JM (0.82) was the highest value, and SKK (0.56) and SW (0.59) were low. The curve pattern of the Mixolab result also gives a quality indication of the flour sample. JM and NS flour had similar pattern at water absorption and gluten strength parameters and BK and HRW had similar viscosity patterns. These results will enable further study for blending Korean wheat cultivar to improve the flour quality.

• Food Science and Preservation
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• v.16 no.1
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• pp.47-52
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• 2009

Bread made after replacement of commercial hard wheat flour with lotus leaf flour (2.5 - 7.5%, w/w) was tested for dough and baking qualities, and by sensory evaluation. The loaf volumes of bread baked with 5% and 7.5% lotus leaf flour were 87% and 80%, respectively, of control (wheat flour only); by contrast, the volume of bread baked with 2.5% lotus leaf flour was 5% greater than control. The hardness of breadcrumbs baked with 2.5% lotus leaf flour was 64.5 g on day 0, and compared with control bread, hardness increased more slowly during storage for 3 days when 5% or 7.5% lotus leaf flour was used. Moreover, dough hardness increased with increasing levels of lotus leaf flour. Lightness decreased with addition of lotus leaf flour, but redness and yellowness significantly increased, in proportion to lotus leaf flour levels. Sensory tests on 2.5% lotus leaf flour bread showed no significant difference compared with control.