• Journal of Nutrition and Health
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• v.22 no.3
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• pp.159-166
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• 1989

The effect of blanching time and power settings of microwave oven on the ascorbic acid retention in seven kinds of vegetables were investigated. The vegetable were blanched for 120 or 180 sec. at three different power setting, 650 watt(high power), 500 watt(medium power) and 160 watt(low power). The retentions of ascorbic acid in cabbage, garland chrysanthemum, mungbean sprout, amaranth and carrot were higher when they were blanched at the high power than those blanced at the lower power stettings. Blanching of spinach and yul-moo(small korean radish) showed that the vitamin was more retained by the medium power heating. Blanching at the low power revealed that the ascorbic acid retention was reduced remarkably as the blanching time increased. From the scoring difference tests the 10-panel members indicated that the texture of three-tested vegetables was more acceptable when they were blanched at the high power setting.

• Korean journal of food and cookery science
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• v.20 no.2
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• pp.219-226
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• 2004

This study was performed to investigate the change of chemical components and antioxidant activities in Hizikia fusiformis(Harvey) OKAMURA with blanching times. For chemical composition, the contents of minerals (K, Ca, Na, Mg, Fe, Cu, Mn and Zn), vitamins (vitamin C, ${\beta}$-carotene and ${\alpha}$-tocopherol) and total polyphenol were analyzed. The antioxidant activity was determined through free radicals (DPPH radical, superoxide anion radical, hydroxyl radical and hydrogen peroxide) scavenging activity and linoleic acid peroxidation inhibitory activity. As the blanching time increased, the contents of all minerals, vitamin C and total polyphenol decreased. However ${\beta}$-carotene and ${\beta}$-tocopherol were not affected by the blanching time. In addition antioxidant activities decreased with increasing blanching time.

• Journal of the Korean Society of Food Culture
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• v.19 no.4
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• pp.369-377
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• 2004

This study was performed to investigate the change of biologically functional compounds and antioxidant activities in Ecklonia cava with blanching times. As biologically functional compounds, the contents of minerals(K, Ca, Na, Mg, Fe, Cu, Mn and Zn), vitamins($vitamin\;C,\;{\beta}-carotene\;and\;{\alpha}-tocopherol$) and total polyphenol were analyzed. And antioxidant activity was determined through free radicals(DPPH radical, superoxide anion radical, hydroxyl radical and hydrogen peroxide) scavenging activity and linoleic acid peroxidation inhibitory activity. As the blanching time increased, the contents of minerals, vitamin C, ${\beta}-carotene$ and total polyphenol were decreased however ${\alpha}-tocopherol$ was not affected by blanching time, and antioxidant activities were decreased with blanching time.

• Journal of the Korean Applied Science and Technology
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• v.34 no.1
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• pp.173-182
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• 2017

This study was conducted to investigate the change of Aaster scaber antioxidative activity, total phenolic compounds and flavonoids during the blanching processes. With two parameters such as blanching time and temperature, response surface methodology and central composite design was used to study the combined effect of blanching time (90 to 162 sec) and blanching temperature (75 to $99^{\circ}C$). We found that antioxidative activity, total phenolic compounds and flavonoids during the blanching processes were influenced by blanching temperature and time. Within process condition, total phenolic compounds and flavonoids were extracted 3.00 - 35.48 mg/g and 2.35 - 8.38 mg/g, respectively. DPPH radical scavenging activity was 42.10 - 67.14%. The change of total phenolic compounds, flavonoids, and DPPH radical scavenging activity was dependent of blanching temperature more than time. The total phenolic compounds was increased as temperature rise, but flavonoids not. However, DPPH radical scavenging activity was increased during the blanching process.

• Food Science and Preservation
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• v.23 no.3
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• pp.310-318
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• 2016

This study was performed to investigate changes in the quality characteristics and chemical compounds in garlic shoots by blanching for different time (0, 0.5, 1, 2, 3, and 4 min). The color (L, a, and b values), texture profile (hardness, springiness, chewiness, gumminess, and cohesiveness), total vitamin C, total sugar, total polyphenol and flavonoid, chlorophyll a and b contents, total pyruvate and thiosulfinate contents of the blanched garlic shoots were examined. As the blanching time increased, the L and b values decreased, while the a value increased. Hardness, chewiness, springiness and gumminess of the blanched shoots were significantly lowered with the increasing blanching time. Vitamin C content of raw garlic shoot was 1.62 mg/100 g while that of the blanched garlic shoots was 0.16~0.24 mg/100 g, implying vitamin C loss into blanching water and destruction by heat. The total sugar and polyphenol contents were fluctuated during blanching, but over 75% of their initial levels were retained under all blanching conditions. The total flavonoid contents increased as the blanching time increased. The chlorophyll a content did not show significant change with blanching time, but the chlorophyll b content significantly decreased. These results suggest that blanching for 2 min could be the best for retaining beneficial compounds and desirable quality of garlic shoot.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.777-787
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• 2016

The purpose of this research was the optimization of Cirsium setidens blanched at various conditions by response surface methodology. Conducted to investigate the change of Cirsium setidens DPPH radical scavenging activity, total phenolic compounds and flavonoids during the blanching processes. With two parameters such as blanching time and temperature, response surface methodology and central composite design was used to study the combined effect of blanching time (70 to 170 seconds) and blanching temperature (70 to $99^{\circ}C$). The changes of DPPH radical scavenging activity, phenolic compounds, and flavonoids on blanching process conditions such as temperature and time were evaluated. After blanching, total phenolic compound was determined from 13.00 to 35.48 mg/ml. total flavonoids was determined from 2.31 to 8.38 mg/ml. DPPH radical scavenging activity was determined from 42.10 to 67.14 %. The optimum conditions were determined to be blanching temperature of $85^{\circ}C$ and blanching time of 150 sec.

• Journal of Bio-Environment Control
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• v.14 no.2
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• pp.114-118
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• 2005

The experiment was conducted to establish the blanching culture of chicon expected to become exporting crop, for preventing Korea fiom importing the ffreign chicon and increasing the growers' profits, the days of blanching culture are based on the 5 treatments such as 10 days, 15 days ,20 days, 25 days, and 30 days. In the blanching culture days of chicory, the growth was good as blanching culture days were longer, there were too many outer leaves, and the ratio of bolting was $16\%$ on the 25 days, $30\%$ on the 30days. On the 10th day, the weight of chicon was light, the hardness was low, the density was low. The quality of chicon had no differences among the treatments. Therefore, the optimal condition for blanching culture of chicory is that the days of blanching culture is 20 days.

• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.201-208
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• 2005

This study was conducted to investigate the effect of blanching time on changes of hazardous factors in leafy vegetables treated by systemic and non-systemic pesticides. Changes of hazardous factors in leafy vegetables treated by systemic and non-systemic pesticides showed the same trend. In changes of microbial counts in leafy vegetables according to blanching time, the total plate count was significantly decreased by blanching and total coliforms were not detected in any of the vegetables. In traceable metal contents of fresh vegetables before washing, the levels in spinach, chard and whorled mallow were 0.042, 0.040 and 0.032 ppm for Pb, 0.020, 0.023 and 0.019 ppm for Cd, and 0.029, 0.034 and 0.030 ppm for As, respectively. Therefore, the levels of Pb, Cd and As in leafy vegetables were very traceable and in terms of food safety there was no problem. On the other hand, the traceable metal contents in leafy vegetables did not show significant difference by blanching and blanching time. Nitrate contents in fresh vegetables before washing were detected at traceable levels. The nitrate contents in spinach, chard and whorled mallow were significantly decreased by $22\%,\;17\%\;and\;14\%$ after blanching time of 5 min, 9 min and 10 min, respectively.

• Journal of the Korean Society of Food Culture
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• v.38 no.6
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• pp.434-441
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• 2023

This study investigated quality characteristics and antioxidant activity of beetroots after blanching. Beetroots were blanched in distilled water, 2% NaCl water, and 2% citric acid water at 100℃ for 3 minutes (the blanched group). The moisture content was highest in the control (CON) at 91.30% (p<0.05), and cooking loss was lowest in the water-blanched beetroot (BW) at 5.39% (p<0.01). Chromaticity decreased after blanching compared to CON (p<0.001). Total polyphenol contents (TPC) and total flavonoid contents (TFC) decreased after blanching, and as a result of comparing the True retention (TR) of the blanching treatment group, BW had the highest with TPC TR 91.22% and TFC TR 70.51%. DPPH and ABTS+radical scavenging activities were highest in the CON, and in the blanching group BW was highest scavenging activity. The total number of microorganisms in the CON group was 2.97 log CFU/g, whereas no microorganisms were detected in the blanched groups. Therefore, this study, blanching in water without additives is the most appropriate method for preserving physiologically active substances and nutrients in beetroots and inhibiting microbial growth.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.415-416
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• 2007