• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1011-1018
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• 2015

The effects of mixing speed (3, 6 and 10 speed) and time (2, 5 and 10 min) on the dynamic viscoelasticity of dough and the baking properties of gluten-free rice bread were investigated. The specific gravity of the dough was not affected by the mixing speed and time before and after fermentation. The elasticity (G') and viscosity (G") of the dough increased and the tan ${\delta}$ (G"/G') decreased with higher mixing speeds and longer mixing times. The specific volume of the gluten-free rice bread was affected by the mixing time in response surface methodology (RSM). The hardness of the gluten-free rice bread showed a decreasing trend as the specific volume for the gluten-free rice bread increased. The appearance of the gluten-free rice bread was symmetrical at high mixing speeds and long mixing times. Overall results indicated that the quality of gluten-free rice bread could be improved by controlling the mixing speeds and mixing times for the dough.

• Culinary science and hospitality research
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• v.24 no.1
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• pp.96-104
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• 2018

The purpose of this study was to promote consumption of rice through production of jeungpyun added with blueberry attracting attention as a functional food material and to develop a functional blueberry supplement suited to the preference of Westernized consumers. For that pupose, we performed physicochemical quality test and sensory test after preparing the jeungpyun added with blueberry powder based on a ratio of 1%, 2%, 3%, and 4% of rice flour. The results of this experiment can be summarized as follows. When the addition of blueberry powder increased, the moisture content in jeungpyun decreased, but there was no significant difference between the samples. The lightness and the yellowness related to chromaticity decreased and redness increased when the addition of blueberry powder increased. The pH of the dough in jeungpyun increased significantly (p<0.001) when addition of blueberry powder increased. As the fermentation progressed, the pH tended to decline. The volume of dough decreased when addition of blueberry powder increased. The volume was the highest after the first fermentation, and decreased after the second fermentation. Viscosity decreased significantly as the addition of blueberry powder increased, and increased as fermentation time increased, and decreased after the third fermentation. A test was conducted to determine difference in characteristics, and the results showed that the color intensity, cell uniformity, blueberry flavor and sweetness were strong when the addition of blueberry powder increased. The results of preference test showed that JB3 containing 3% blueberry powder had the best appearance, flavor and overall acceptance.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1374-1380
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• 2012

The changes in yields and nutritive composition of whole crop wheat (Triticum aestivum L.) during maturation and effects of maturity stage and lactic acid bacteria (LAB) inoculants on the fermentation quality and aerobic stability were investigated under laboratory conditions. Whole crop wheat harvested at three maturation stages: flowering stage, milk stage and dough stage. Two strains of LAB (Lactobacillus plantarum: LAB1, Lactobacillus parafarraqinis: LAB2) were inoculated for wheat ensiling at $1.0{\times}10^5$ colony forming units per gram of fresh forage. The results indicated that wheat had higher dry matter yields at the milk and dough stages. The highest water-soluble carbohydrates content, crude protein yields and relative feed value of wheat were obtained at the milk stage, while contents of crude fiber, neutral detergent fiber and acid detergent fiber were the lowest, compared to the flowering and dough stages. Lactic acid contents of wheat silage significantly decreased with maturity. Inoculating homofermentative LAB1 markedly reduced pH values and ammonia-nitrogen ($NH_3$-N) content (p<0.05) of silages at three maturity stages compared with their corresponding controls. Inoculating heterofermentative LAB2 did not significantly influence pH values, whereas it notably lowered lactic acid and $NH_3$-N content (p<0.05) and effectively improved the aerobic stability of silages. In conclusion, considering both yields and nutritive value, whole crop wheat as forage should be harvested at the milk stage. Inoculating LAB1 improved the fermentation quality, while inoculating LAB2 enhanced the aerobic stability of wheat silages at different maturity stages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1819-1825
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• 2015

This study was carried out to investigate the effect of hydrocolloids [hydroxypropylmethyl cellulose (HPMC), xanthan gum (XG), guar gum (GG), and glucomannan (GM)] on the physicochemical properties of bread flour dough containing rice flour. In amylograph analysis, the significantly lowest gelatinization temperature was obtained in dough with XG (P<0.05). XG revealed the highest maximum viscosity while GM revealed the lowest. In viscograph test, the lowest gelatinization temperature and maximum viscosity showed the same result as in the amylograph. Breakdown value was also highest in dough containing XG, but lowest in the control and dough containing HPMC. Setback value was highest in dough containing HPMC, but lowest in dough containing XG. In farinograph analysis, consistency was greatest in dough with HPMC and XG. Hydrocolloids affected water absorption, which was highest in dough containing GM. Development times of dough containing HPMC and XG were low. Stability was lowest in dough with XG. Degree of softening was reduced in dough containing HPMC and GG compared to the control but increased in dough containing XG and GM. Dough containing HPMC and GG showed the largest volume at 3 h of fermentation. Dough with HPMC showed the lowest pH value. Hydrocolloids in this study affected physicochemical properties of dough.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.55-60
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• 2005

Frozen dough made by sponge and dough method using sweet dough formula was quickly frozen at $-40^{\circ}C$ and stored for 8 weeks at $-20^{\circ}C$. Effects of vital wheat gluten on number of yeast cells, bread volume, specific loaf volume, hardness, and sensory properties of bread were investigated. Dough added with 4% vital wheat gluten showed higher yeast cell survival rate during freeze storage and larger specific loaf volume than other doughs. Hardness value increased with increasing amount of vital wheat gluten added, whereas, in frozen dough stored more than 4 weeks, dough added with 2% vital wheat gluten showed lower hardness value than others. Bread made with 4% vital wheat gluten showed highest sensory score.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.359-364
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• 2003

Frozen doughs for danish pastries were made by straight dough method to study the effect of thawing temperature on the quality of pastries. Danish pastry doughs were immediately frozen at -40 $^{\circ}C$ quickly after make-up and stored for 6 weeks at -20$^{\circ}C$ and baked after thawing and fermentation a week. Thawing temperature and fermentation time were controled to 3 hr at 5$^{\circ}C$, 2 hr at 10$^{\circ}C$, and 1.5 hr at 20$^{\circ}C$, respectively. The number of survival yeast cells in dough and the volume, the moisture content, the texture of danish pastries were investigated. Survival yeast cells showed the highest number at thawing temperature of 5 $^{\circ}C$. The volume of danish pastries decreased significantly according to the increase of frozen storage time and danish pastries thawed at 5$^{\circ}C$ revealed the largest volume. In moisture contents of danish pastry, there was no significantly difference without regard to the thawing temperature but showed the highest moisture content at thawing temperature of 20$^{\circ}C$. Danish pastries thawed at 5$^{\circ}C$ accomplished the best texture in the resulting pastry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.660-665
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• 2008

The aim of this work was to investigate the microbiological and physicochemical properties of the rice sourdough for Jeungpyun prepared by mixed culture of Saccharomyces cerevisiae (S. cerevisiae) and Leuconostoc mesenteroides (L. mesenteroides) strains. The rice sourdough was fermented with S. cerevisiae and L. mesenteroides strains in rice dough for 24 hours at $30^{\circ}C$. Growth of L. mesenteroides strain was decreased after inoculation, however, it increased again after 18 hours of dough fermentation, and the growth of S. cerevisiae showed a typical growth pattern. Also, total aerobic microorganisms counts in rice sourdough were decreased due to the produced organic acids and ethanol during dough fermentation. These products led to a favorable fermentative quotient (FQ; molar ratio between lactic to acetic acid) value of $1.9{\sim}3.2$ and more stable fermentation for rice sourdough formation. The expansion ratio and viscosity were considerably increased by mixed cultivation of S. cerevisiae and L. mesenteroides strains. Addition of the brown rice at 10% (w/w) to dough preparation increased the relative expansion ratio to the highest value.

• Food Science and Preservation
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• v.12 no.6
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• pp.583-590
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• 2005

Dough fermentation characteristics and quality characteristics of bread added with different concentration(0, 30, 40 and $50\%$ against water) of submerged-culture broth of Fomitopsis pinicola mycelium (CM) were investigated There were positive correlations between CM concentration and dough pH(r=0.98), acidity(r=-0.88), dough thickness(r=0.95) and dough strength(r=0.95). Baking loss rate was decreased with increasing of CM concentration. There was no significant difference between loaf volume index and CM concentration ($30\~40\%$, but the index of CM $50\%$ bread was lower than that of control. L* value of top crust in the CM $50\%$ bread was significantly lower than those of CM $0\~40\%$ bread, while the value of internal tissue was increased with increasing of CM concentration. In the CM $30\~40\%$ bread, hardness was lower, but there were no significant difference in cohesiveness, springiness, chewiness and brittleness compared with control. Appearance, color, taste, texture and overall acceptability of CM $30\~40\%$ bread were similar to those of control. In the results estimated by correlation analysis, the increased pH of the dough by adding CM allowed lowering hardness of the bread By adding CM in bread, retrogradations were delayed, and growth of mold was decreased during storage. In conclusion, the optimum concentration of CM in bread which showed anti-diabetic effect as well as not dropped quality characteristics were $30\~40\%$.

• Food Engineering Progress
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• v.21 no.2
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• pp.132-137
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• 2017

The purpose of this study was to optimize dough properties using response surface methodology (RSM) and to demonstrate the performances of dough prepared under optimized conditions. Dough mixed with yeast, margarine, salt, sugar and wheat flour was prepared by fermentation process. Hardness, cohesiveness and springiness of dough were selected as critical quality attributes. The critical formulations (yeast and water) and process (fermentation time) variables were selected as critical input variables based on preliminary experiment. Box-Behnken design (BBD) was used as RSM. As a result, the quardratic, the squared and the linear model respectively provided the most appropriate fit ($R^2$>90) and had no significant lack of fit (p>0.05) on critical quality attributes (hardness, cohesiveness and springiness). The accurate prediction of dough characteristics was possible from the selected models. It was confirmed by validation that a good correlation was obtained between the actual and predicted values. In conclusion, the methodologies using RSM in this study might be applicable to the optimization of fermented foods containing various wheat flour and yeast.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.87-94
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• 2008

In this study, a nanatural fermentation starter formulation was developed for manufacturing bread products by substituting baker's yeast with naturally fermented raisin extract and sourdough. Four experimental groups containing 2.5, 5.0, 7.5, 10% naturally fermented raisin extract per 2,000 g of flour were compared based on quality characteristics, including the fermentation power on dough expansion, specific volume, baking loss, water activity, color, textural characteristics, and internal surface appearance. The activities of the naturally fermented raisin extract were examined in terms of pH changes, total titratable acidity, brix, and viable yeast counts. The raisin extract, which was cultured for 7 days at 30$^{\circ}C$, smelled of alcohol and produced $CO_2$. Yeast were also found in the extract after separation. As the incubation time of the raisin extract and sourdough increased, pH decreased, while total titratable acidity increased. The brix of the raisin extract increased until the $2^{nd}$ day of fermentation, and viable yeast counts increased until the $5^{th}$ day however, these gradually decreased by the $7^{th}$ day. The fermenting power on dough expansion increased in the bread with increasing incubation time. The bread samples containing 7.5% and 10% raisin extract had significantly higher specific volumes than the other samples. Baking loss was minimal with the 2.5% extract substitution. In analyzing the crumb, water activity, redness, and yellowness were highest in the 10.0% raisin extract bread samples, and lightness was maximal in the 5.0% group. In terms of textural characteristics, hardness was lowest with the 2.5% extract substitution. Gumminess, springiness, and chewiness were not significantly different among the bread samples. Cohesiveness was highest at the 7.5% extract substitution level, and resilience was lowest at the 10% level. In conclusion, based on the results, a natural fermentation starter formulated with 2.5% naturally fermented raisin extract (1 part raisins and 1.5 parts water) and 70% sourdough (1 part rye flour and 1 part water) has high potential as a baker's yeast substitute for making naturally fermented bread.