• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.22-30
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• 2014

In this study, purple sweet potato bread was prepared by the addition of 0.005%, 0.010%, 0.015% and 0.020% hemicellulase. It's effect on product quality and consumer evaluation were examined. The results showed that the dough pH and total titratable acidity were not significantly different between samples. In the fermentation power of dough expansion, a 0.015% addition sample was the highest between the samples. The bread pH decreased significantly as hemicellulase was increased, whereas. Bread total titratable acidity was significantly decreased. The addition of hemicellulase samples were significantly higher in specific volume and baking loss than the control sample. The moisture content was not significantly different between samples. In colors, the lightness of the control sample was the highest, the redness of the 0.020% addition sample was the lowest while the yellowness of the control was the lowest. The hardness and the fracturability decreased significantly as hemicellulase was increased. The resilience indicated reverse effects. In consumer evaluation, the color and softness were not significantly different between samples. And the hemicellulase addition of samples was higher in flavor than that of the control sample. The overall acceptability was the highest at 5.67 with a 0.010% addition sample. According to these results, the addition of 0.010% hemicellulase in purple sweet potato bread would be the optimum level.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.625-632
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• 2008

Rye-wheat mixed bread samples made with substitutions of 20, 40, 60 and 80% sourdough, and control made with the addition of naturally fermented raisin extract, were examined for quality characteristics such as pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, water activity, color, texture, external and internal surface appearance, and sensory qualities, in order to determine the optimal ratio of sourdough in the formulation. As the incubation time of sourdough increased, pH decreased, while total titratable acidity increased. The pH of rye-wheat mixed doughs decreased with increasing sourdough content, but total titratable acidity increased. The rye-wheat mixed breads prepared with substitutions of sourdough had higher pH and lower total titratable acidity than the control group. Fermentation power of dough expansion of rye-wheat mixed doughs increased with increasing incubation time. Specific volume was maximum on the 20% substitution sourdough. Baking loss was inferior with the 80% substitution sourdough. Water activity and lightness was minimum on the control group. The higher amounts of sourdough showed the higher tendency of lightness, redness and yellowness. In the texture characteristics, hardness, gumminess, and chewiness was minimum on the control group and tended to increase with higher substitution of sourdough. Substitution of sourdough showed decrease adhesiveness. Fracturability, cohesiveness, and resilience of all rye-wheat mixed breads were not significantly different. Springiness was maximum on the 20% substitution sourdough and minimum on the 40%. A side of loaf of rye-wheat mixed breads, except for 20%, had a poor break and shred. In sensory evaluation, as substitution amount of sourdough increased, the scores of color and consistency of crumb, uniformity of crumb pore, gumminess, and overall acceptability decreased; while the density of crumb pore, springiness of crumb, aroma of rye flour, sourness, and bitterness showed the reverse effect; the 20, 40, and 60% sourdough samples obtained fairly good scores. In conclusion, these results indicated that $20{\sim}60%$ of sourdough could be very useful as a substitute for baker's yeast in developing rye-wheat mixed bread.

• Korean journal of food and cookery science
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• v.26 no.5
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• pp.503-510
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• 2010

Different amounts of black garlic extract(0, 1, 3, 6, 9 and 12%(W/W)) were added to white pan bread, and the quality characteristics were evaluated. The pH and density of dough was decreased with increasing concentration of black garlic extract. There was no marked difference in the fermentation power of the dough expansion among the samples. The pH of bread decreased, and there were no significant differences in baking loss rate, dough yield or bread specific volume as the concentration of black garlic extract was increased. Regarding crust and crumb color values, lightness gradually diminished with increased amounts of black garlic extract in bread, whereas redness and yellowness increased. For measurement of texture, the highest hardness and gumminess of bread were observed in the 1% added group, and there was no remarkable difference between the 3% added group and control. Sensory evolution was the highest when 6% black garlic extract was added, but there were no significant differences in terms of color or overall acceptability. The results imply that addition of black garlic extract to white pan bread created a healthy and functional bread.

• Food Science and Preservation
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• v.10 no.4
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• pp.476-481
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• 2003

As its high functional properties to be used as medicine or food, the cultivation of Agaricus mushroom has been expanded and iぉ commercialization required better storage methods that can extend its functional and nutritional value for longer period. We selected drying as the most plausible method to meet such requirement, and several drying conditions were investigated to locate the optimum drying condition that can be used to keep the quality of mushroom. Drying temperature of 50$^{\circ}C$, 60$^{\circ}C$, 100$^{\circ}C$ were selected to trace the drying time required to achieve the moisture content of mushrooms less than 10%. The drying temperature at 50$^{\circ}C$ required 29 hrs of drying time, while 100$^{\circ}C$ required only 10 hrs of drying tune. However, their quality characteristics on the following categories, on the degree of browning and color were investigated to find the optimum drying condition. In addition, sensory evaluation was conducted to evaluate the quality of dried mushrooms produced by each drying condition. The browning of the mushroom was evidently increased as the higher drying temperature was used and 50$^{\circ}C$ drying produced the most desirable quality of all in pileus or stipe. The aeon of browning intensified by drying temperature was comparable to the result of whiteness index value, which resulted lower L values as drying temperature increased. and the 50$^{\circ}C$ drying resulted the most highest L values among all drying samples. As the browning and whiteness results implied, the sensory evaluation result gathered from the present research indicated that the 50$^{\circ}C$ drying was the most favorable drying condition by scoring the most highest average scores on flavors, color, appearance, and overall acceptability conducted by the 10 evaluation panels.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.109-116
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• 2008

In this study, the breads with medicinal herbs (MH) composites showing immunostimulating activity were prepared and their characteristics were examined. Fourteen kinds of medicinal herbs were extracted with hot water and divided into 3 groups (MH-1, MH-2, MH-3) based on their contents. All groups showed immunostimulating activity in terms of macrophage phagocytosis, nitrite production, cytostatic activity and cytokine production. In the preparation of breads containing MH extracts of various contents (0, 30, 50, 70, and 100%), there was no significant difference among dough pHs of all groups after first fermentation, but loaf volume was significantly (p<0.05) increased in 70% added group while decreased in 30%, 50%, and 100% added groups compared to the control. The "a" and "b" values of bread crumb increased with the content of MH extracts while "L" value decreased, but these values of bread crust were similar to the control group. Most improvements in hardness, adhesiveness, gumminess and chewiness of bread were noticed by the addition of 70% MH extracts, but those of springiness, cohesiveness and resilience were mostly by the 50% addition ones. Through the sensory evaluation, it was revealed that mouth feeling, taste and overall preference decreased at breads containing 70% and 100% extracts, although appearance and crumb texture were not significantly (p<0.05) different among all groups.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.322-340
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• 2021

Due to climate change and its consequential spring temperature rise, flowering time of Robinia pseudoacacia has advanced and a simultaneous blooming phenomenon occurred in different regions in South Korea. These changes in flowering time became a major crisis in the domestic beekeeping industry and the demand for accurate prediction of flowering time for R. pseudoacacia is increasing. In this study, we developed and compared performance of four different models predicting flowering time of R. pseudoacacia for the entire country: a Single Model for the country (SM), Modified Single Model (MSM) using correction factors derived from SM, Group Model (GM) estimating parameters for each region, and Local Model (LM) estimating parameters for each site. To achieve this goal, the bloom date data observed at 26 points across the country for the past 12 years (2006-2017) and daily temperature data were used. As a result, bloom dates for the north central region, where spring temperature increase was more than two-fold higher than southern regions, have advanced and the differences compared with the southwest region decreased by 0.7098 days per year (p-value=0.0417). Model comparisons showed MSM and LM performed better than the other models, as shown by 24% and 15% lower RMSE than SM, respectively. Furthermore, validation with 16 additional sites for 4 years revealed co-krigging of LM showed better performance than expansion of MSM for the entire nation (RMSE: p-value=0.0118, Bias: p-value=0.0471). This study improved predictions of bloom dates for R. pseudoacacia and proposed methods for reliable expansion to the entire nation.