• 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.

• Korean journal of food and cookery science
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• v.29 no.6
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• pp.815-823
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• 2013

To provide rice products in substituted for wheat flour and wheat products in elementary school foodservice, the survey for nutritionist in elementary school was accomplished from November 3rd to 8th, 2012 in Gwangju and Jeonnam area, and obtained 83 and 95 copies from Gwangju and Jeonnam, respectively. Most nutritionists were graduated from universities and had careers longer than 15 years. The nutritionists (56.7%) had worked at the schools where food allergy students were enrolled. The consumption of wheat flours per one student per month was 677.8 g in Gwangju and 707.4 g in Jeonnam. Udon and Jajangmyeon were more popular wheat products. Nutritionist agreed positively that rice products instead of wheat products were possible to use for meal menu (73.5% in Gwangju and 61.1% in Jeonnam). The frequent use of rice products was tteokbokkitteok, because of students' preference. The rice bread and tteokguktteok were preferred significantly higher in Jeonnam than in Gwangju. The advantages of rice products which perceived by nutritionists were benefits for health, digestive easily, and high nutritious, but their disadvantages were hard-to-find and expensive. The nutritional values of rice and recipes for cooking rice products were required as educational program for increasing consumption of rice products. Demonstration for rice cooking methods was selected most popular program. The application of rice products for school foodservice was preferred to Jeonnam compared to Gwangju (p<0.001). As a consequence, the nutritionists working in elementary school in Gwangju and Jeonnam area have positive thought about using rice products in school foodservice, if educational program of school foodservice menu using rice products should be demonstrated them.

• Korean Journal of Food Science and Technology
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• v.8 no.4
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• pp.236-241
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• 1976

A barley (20-30%)-wheat (80-70%) flour gave generally acceptable noodle-making characteristics, in which naked barley flour showed somewhat better results than covered barley flour. And also for over 40% barley flour in the barley-wheat flour, the addition of xanthan gum improved the noodle-making characteristics. A naked barley-defatted soy flour could make dried noodles with only high NSI (Nitrogen Solubility Index) defatted soy flour, however this mixture was not considered to be feasible for noodle-making. In cooking characteristics of barley-wheat flour noodles, naked barley flour was more acceptable than covered barley flour and xanthan gum influenced the water absorption and volume expansion of noodles during cooking. The firmness, cohesiveness and gumminess in cooked noodles made of the barley-wheat flour increased and then decreased as the amounts of barley increased. The mixing of defatted soy flour (high NSI) to naked barley flour increased the firmness and gumminess of cooked noodles.

• 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.

• Korean Journal of Food Science and Technology
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• v.7 no.2
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• pp.85-90
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• 1975

Milling yields from naked barley varieties were found to be approximately 10% greater with a constant milling rate than yields from covered barley varieties. Also, the ash content of flour from naked barley varieties is less than from covered barley. Amylograms from barley flours showed higher viscosity for the naked varieties than for covered varieties. Farinograms of doughs prepared from 10:90 and 30:70 barley: wheat flour mixtures indicated general deterioration of bread baking qualities with increasing additions of barley flour. A comparison of bread baking qualities between naked and covered barley flours showed greater stability, greater elasticity, and less weakening with naked barley flour than with covered barley flour.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1043-1048
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• 2004

This study was carried out to investigate the effect of soy protein dispersibility on the bread making properties when Doenjang powders (DP) were added to the bread formula at the levels of 2.5 or 5.0%, comparing with full fat (FSF) or defatted (DSF) soy flours which contain same protein contents as those of DP. Protein dispersibility indices (PDI) for DP, FSF, DSF and strong wheat flour were 57.1, 7.3, 10.8 and 32.8%, respectively. Addition of DP decreased significantly the resistance to extensibility of wet gluten and increased its extensibility. However, FSF and DSF showed different changes in gluten rheology due to their PDI. In correlation coefficient values, PDI affected positively both gluten extensibility (r=0.98, p<0.01) and ovenspring (r=0.88, p<0.05) resulting in loaf volume and texture improvement of bread with addition of DP.

• Human Ecology Research
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• v.58 no.1
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• pp.121-130
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• 2020

This study evaluated the quality characteristics of semi-dried noodles prepared with various dry rice flours (0, 25, 50, 75, and 100%) in order to develop the most preferred noodle recipe and to increase rice consumption. Amylography measured the viscosity of composite dry rice flour-wheat flour and indicated that the gelatinization point and maximum viscosity decreased as the level of dry rice flour increased. Both L and a values for cooked noodle significantly increased as the dry rice flour increased; however the L value decreased for uncooked of noodles. Weight, volume and water absorption of cooked semi-dried noodles significantly decreased as the dry rice flour increased; however the turbidity of soup increased. Texture properties such as hardness, springiness, cohesiveness, and adhesiveness decreased as the level of dry rice flour increased. As the amount of rice flour added increased, large particles of gluten were reduced while smaller particles of starch increased by scanning electron microscopy (SEM). The color, taste, and overall preference of 75% noodles were the highest in the sensory characteristics. The results, showed that the addition of dry rice flour positively affects the overall sensory characteristics of semi-dried noodle with 75% representing the optimal level for addition.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.128-134
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• 2000

Cysteine, a thiol group-containing reducing agent which is known to relax the strain and increase the viscosity of dough, was added to Korean and imported wheat flour noodles to investigate the effect on the properties of raw, dried, and cooked noodles and to determine the optimum cooking time and amount to improve the color of noodles. Addition of cysteine up to 1% of flour (8.25 mmole/100 g flour) was not effective in increasing the brightness of raw and dried noodles and in changing the water activity of dried noodle. However, cysteine improved the brightness of cooked noodle made of both Korean and imported wheat flours. Also, there were notable differences in cooking and sensory properties of cysteine-added cooked noodles such as less firm and stickier texture due to the extraction of organic compounds into broth. When the noodles were cooked for their optimum cooking time, no difference was noticed in the texture and overall preference regardless of the addition of cysteine. Overall, the addition of 1 % cysteine increased the brightness of cooked noodles and reduced the cooking time.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.878-885
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• 1997

Effect of various ingredients and cooling methods on the quality of modified Jeung-pyun(traditional Korean steamed rice cake) were studied. Three different kinds of wheat flours(strong, medium, and weak) were studied to evaluate the volume and firmness of Jeung-pyun. Weak flour showed the maximum volume and good sensory results. The optimum ratio of ingredients was flour : water ; sugar ; Tak-Ju=100 : 20 : 20 : 50 for steaned Jeung-pyun. When three different cooking methods were compared, the maximum volume showed from convection oven method, but the crust color of Jeung-pyun was like bread. Steaming method showed higher volume than that of product heated by microwave method. The optimum formula ratio for the microwave method was flour ; water ; sugar ; Tak-Ju = 100 : 30 : 20 : 50, which required 10% higher added water content than that of steaming. When wheat flour was used instead of rice flour, the addition of 5% normal corn starch increased volume of both steamed and microwave cooked products. In the case of added modified starches to Jeung-pyn, 5% $\alpha$-waxy corn starch showed the highest volume in steaming method. When rice flour was used, the addition of 5%$\alpha$-waxy corn starch also showed highest volume f both steamed and microwave cooked products. The firmness of steamed wheat flour Jeung-pyun, containing 5%$\alpha$-corn starch was higher firmness than that of control and other added samples. Microwave cooked products showed two or three times higher firmness of steaming products. The use of wrap(uni-wrap) and stabilizer(METHOCEL) decreased the firmness of microwave cooked wheat flour Jeung-pyun to 200~300g compared with that of untreated Jeung-pyun.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.149-152
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• 1984

Fifiy-five wheat samples were studied to obtain the basic information on the varietal differences of physicochemical characteristics and cookie baking potentiality in wheat breeding lines. Alkaline water retention capacity (AWRC) value had a correlation coefficient of $0.51^{**}$ with sedimentation value, of $0.45^{**}$ with protein content, and of $0.47^{**}$, with Pelshenke value. The highly significant correlation coefficient was obtained for cookie diameter vs. AWRC value $(-0.98^{**})$ and cooki diameter vs. protein content $(-0.46^{**})$. Farinograph absorption is highly correlated with AWRC value $(r=0.77^{**})$ and with cookie diameter $(r=-0.73^{**})$. Farinograph band width had a correlation coefficient of $-0.49^{**}$ with AWRC value, and of $0.44^{**}$ with cookie diameter.