• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.160-166
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• 1989

This study was conducted to investigate whether egg-shell may be used as a mineral sourceor leavening agent in breadmaking. In Korea the waste volume of egg shell has been estimated at about 28,694 tons per year. Carbon dioxide generation maxima were established for barking powder$(153{\pm}3ml/g)$, egg-shell(205in reaction with lactic acid) and yeast$(115{\pm}3ml/sugar\;g)$. Gas release time required for each substance to reach $CO_2$ maximum was, for baking powder 7 minutes, for egg-shell 45 mins and for yeast 240 mins. Particle size of egg-shell in breadmaking was suitable more than 20 mesh (-). When egg-shell only was added to the basic formular without including lactic acid, no leavening effect was observed. However, when lactic acid and egg-shell were used together, the leavening effect was more or less equivalent to that of yeast(control). Addition of egg-shell was found to increase calcium content of bread products without noticeable altering flavor, as compared with control. Joint use of egg-shell was organic acids in breadmaking was shown to have potential in time saving, volume increase and yeast saving.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.348-354
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• 2006

Baking quality of dough made of flour substituted with insoluble ${\beta}-glucan$ (10, 20, and 30%), functional food material produced from Agrobacterium spp. R259 KCTC 10197BP, was evaluated. Optimum time to reach 1st stage of dough fermentation decreased with increasing ${\beta}-glucan$ content, whereas mixing time increased. Addition of ${\beta}-glucan$ did not affect pH of dough. Hunter color L, a, and b values of dough added with up to 20% ${\beta}-glucan$ were not significantly different from those of control. Rheology properties such as cohesiveness and springiness of ${\beta}-glucan$ added dough increased, while hardness and gumminess decreased. Amylogram showed addition of ${\beta}-glucan$ to flour lowered setback and consistency, which are suggested to delay retrogradation.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.174-182
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• 2004

Hygienic standards for pizza specialty restaurant located in Seoul during summer, 2000 were established based on HACCP concept by measuring temperature, time, pH, $A_{w}$ and microbiological assessments of pizza, and evaluation of hygienic conditions of kitchens and workers. Kitchen and worker conditions were average 1.2 and 1.0 (3 point Sly's scale), respectively, Microbial contaminations occurred at $5-60^{\circ}C$, pH above 5.0, and $A_{w}$ (0.93-0.98). Microbial assessments for pizza processing revealed $1.5{\times}10^{2}-3.9{\times}10^{8}\;CFU/g$ of TPC and $0.5{\times}10^{1}-1.6{\times}10^{7}\;CFU/g$ of coliforms, exceeding standards ($TPC\;10^{6}\;CFU/g\;and\;coliform\;10^{3}\;CFU/g$) established by Solberg et al., although significantly decreased after baking. S. aureus was not discovered, but Salmonella was found in onions. Tools and containers such as pizza cutting knife, topping container, serving bowl, pizza plate, working board, and dough kneading board contained $6.2{\times}10^{2}-1.1{\times}10^{9}\;CFU/g$ of TPC, $2.0{\times}10^{1}-6.2{\times}10^{3}\;CFU/g$ of coliforms. Workers' hands contained $3.1{\times}10^{4}\;CFU/g$ of TPC and S. aureus as compared to safety standards of Harrigan and McCance (500 and 10 CFU/g of TPC and coliforms per $100cm^{2}$). CCPs (critical control points) were determined as receiving, topping, and baking according to CCP decision tree analysis. Results suggest purchase of quality materials, careful monitoring of time and temperature, hygienic use of tools and utensils, and sanitary practicer by workers are recommended as control points for safe pizza production.

• The Korean Journal of Food And Nutrition
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• v.11 no.4
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• pp.369-374
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• 1998

This study was conducted to investiagte influences of cold aged dough on the quality of bagutte. After 2 hours fementing, the dough was divided 2 parts and they were stored in the refrigirated adjusted 1∼-1$^{\circ}C$. The cold aging time was 24, 48 hours respectivley. After 2 hourse fermentation, the dough's pH was 5.45 and 24, 48 hours cold aged dough were 4.99, 4.81. During cold aging, the difference of pH was not significant. The main organic acids in the baguette were lactic acid, acetic acid and malic acid, Among these organic acids, the acetic acid was the largest quantity regardlessly in different fermentation and the cold aging acids, time. Right after baking, the enthalphy of all samples were almost same even thought in different cold aging time, but during different storage periods they showed the difference of retrogradation by the increase of the enthalphy. 24 hours cold aging baguette had the best taste, aroma and texture in bread's score sheet.

• The Korean Journal of Food And Nutrition
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• v.32 no.2
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• pp.79-88
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• 2019

This study was conducted to evaluate the characteristics of bread and the rheology of flour dough containing jochung. In the farinogram test, the addition of jochung changed water absorption, development time and mixing tolerance index for making bread As the amount of jochung increased, the water absorption, mixing tolerance index decreased and the development time increased. In the extensograph test, the degree of extension decreased with increasing of jochung content whereas degree of resistance was enhanced with addition of jochung. After fermentation treatment, the volume of the dough with 20% sucrose were less than that of the dough containing 20% of jochung. The dough with 5% jochung showed the lowest dough raising power compared to the other doughs. The bread consisting of 15% jochung showed the highest volume of loaf and specific volume. Therefore, high quality of bread can be achieved by adding jochung instead of sucrose for making bread.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.1
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• pp.59-64
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• 1999

This paper investigated optimum drying time of PCB and the relationship between humidity in PCB and solderability. As experimental results, soldering was improved with increasing drying time. The wetting time of a dry specimen was shorter about 0.2 seconds than that of a wet specimen. The wetting force was Increased by 2~4mN after drying the wet specimen. When PCB was dried over 30 minute, solder defects and tensile strength of soldered joints was optimized. Effects of drying tome of PCB on the soldering, wetting curve, soldered shape, solder ball, and tensile strength, were investigated.

• Journal of Food Hygiene and Safety
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• v.18 no.2
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• pp.87-93
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• 2003

This study was performed to investigate aflatoxin reduction resulting from the pre-treatment and the cooking and processing of corn. Aflatoxin was produced by Aspergillus parasiticus ATCC 15517 on a type of corn imported from the United States. The aflatoxin-produced com (AC) was pre-treated in three ways in order to reduce aflatoxin: exposure to sun light for 7 days (SC); ultraviolet irradiation for 56 hours (UC); and washing with water three times (WC). Four kinds of cooking and processing methods (boiling, steaming, baking, and popping) were used to reduce aflatoxin in the AC control, SC, UC, and WC. These treatments produced com gruel, com cakes, com bread and popcorn. The aflatoxin content in the samples was determined by high performance liquid chromatography. The total aflatoxin level of the AC was significantly decreased by sun light and UV (p<0.05), and decreased by washing. After cooking and processing the AC, SC, UC, and WC, and averaging the total aflatoxin levels in the final products, the greatest reduction was found in the com gruel, then the popcorn, then the corn cakes, and the least reduction in the com bread. These results indicate that sunlight and ultraviolet energy could be effective factors in aflatokin degradation in corn before cooking and processing. This study also indicates that boiling, steaming, baking and popping were helpful in reducing the aflatoxin level in the com and that the most helpful factors were exposure time to heat. More research is needed to reduce the aflatoxin level down to below the maximum tolerable level of aflatoxin in foods.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1295-1300
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• 1998

This study was conducted to investigate the effect of soybean protein isolate (SPI) on the baking qualities of bread which was made of composite flour blended with SPI extracted at acidic (pH 2.0, 3.0), neutral (pH 7.0) and alkaline (pH 10.0, 12.0) conditions. The mixogram showed that water absorption of composite flour dough blended with SPI extracted at pH 2.0 and 12.0 was higher than that of 100% wheat flour dough, and mixing time was shorter than that of 100% wheat flour dough. No differences were found between the composite flour blended with SPI at level of 5% and 100% wheat flour on the loaf volume of bread. The loaf volume of bread made of composite flour blended with $SPI_2\;AND\;SPI_3$ at level of 10% was lower than that of 100% wheat flour, but that of $SPI_7,\;SPI_{10},\;and\;SPI_{12}$, which had higher emulsion capacity than $SPI_2,\;SPI_3$ was similar to that of 100% wheat flour. No differences were found between the composite flour blended with SPI at level of 5% and that of 100% wheat flour on springiness, chewiness, cohesiveness, gumminess, adhesiveness and hardness of bread. The composite flour blended with SPI at level of 10% was similar to 100% wheat flour on springiness, chewiness, cohesiveness, gumminess, adhesiveness and hardness of bread except for chewiness, gumminess and hardness of $SPI_2,\;and\;SPI_{12}$ which were significantly higher than that of 100% wheat flour (P<0.05).

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.448-456
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• 2008

In this study, domestic wheat white breads were prepared with the substitution of 1.5, 3.0, 4.5, and 6.0% Nelumbo nucifera G. tea powder(NNTP). The samples and a control were then compared with regard to quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities in order to determine the optimal ratio of NNTP in the formulation. As the NNTP contents increased, the pH of dough and bread, baking loss, and lightness decreased, whereas the total titratable acidity of dough and bread increased. The fermentation power of dough expansion increased with increasing incubation time. The NNTP samples evidenced significantly higher specific volume, greenness, yellowness, resilience, and crumb consistency than were observed in the control group. However, hardness and fracturability evidenced the opposite effect. The water content and uniformity of the crumb pores were highest at a substitution level of 1.5%, and were lowest at a level of 4.5%. Crumb color, flavor, and delicious taste decreased with increasing NNTP contents, whereas lotus leaf flavor, astringency, bitterness, and off-flavor increased. Density of the crumb pore and crumb springiness were not significantly different among the samples. Softness, chewiness, and overall acceptability were maximal with the 1.5% substitution, and were minimal in the 6.0% group. In conclusion, our results demonstrate that $1.5{\sim}3.0%$ NNTP may prove quite useful as a substitute for domestic wheat flour in the production of white bread, and may evidence favorable nutritional and functional properties.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.188-194
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• 2000

Effects of native and RS-3 type resistant starches prepared from autoclaved-cooled amylomaize VII(AVII) and normal maize starches(NMS) on the rheological and baking properties of wheat flour dough and quality of breads were investigated. In farinogram, water absorption and dough development time were increased, but stability was reduced by the addition of RS. The addition of native starches or resistant starch made from AVII to wheat flour improved the total volume and specific loaf volume of bread compared with the control(no addition), but the addition of NMS-RS reduced those. During the storage of bread at room temperature, the moisture content of control was decreased but those of native starch- or RS-added breads remained constantly. AVII-RS- or NMS-RS-added bread was evaluated to have good overall acceptability compared with control by elementary school students. The addition of enzyme-resistant starch to bread regardless of botanical sources of starch not only improved the overall acceptability and nutritional benefits but also improved the sensory acceptability.