• 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.

• Food Science and Preservation
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• v.23 no.7
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• pp.939-944
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• 2016

The aim of this study was to establish an optimum blanching condition for outer cabbage leaves to increase utilization of the byproduct. Outer leaves of Kimchi cabbages were cut to size ($4{\times}4cm$) and blanched at 80, 90, $100^{\circ}C$ for 1, 3, and 5 min. Subsequently, weight loss, pH, total bacteria, coliform and texture properties were investigated. Sensory evaluation of a ready-to-cook soup prepared from blanched outer leaves was investigated to determine whether the quality of the blanched outer leaves was acceptable. Both weight loss and pH of outer leaves of Kimchi cabbage were increased by blanching. Compared to raw samples, total bacterial counts decreased and coliform bacteria were not detected. The hardness of raw leaf samples was $1.5kg{\cdot}force$ (N). Sample hardness was 18.7~21.7% lower after blanching for 3 min and 34.8~36.7% after blanching for 5 min. Sensory evaluation of outer leaves blanched at $100^{\circ}C$ for 5 min revealed significant differences from the other treatments (p<0.05). In addition, sensory evaluation scores for texture and appearance of outer leaves blanched at $100^{\circ}C$ for 3 min were higher than those for commercially available products. The results of this study indicate that blanching can be effective for developing a food product from the outer leaves of Kimchi cabbage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.572-578
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• 1999

This study was conducted to investigate processing condition and characteristics of chestnut paste. The kinds of chestnut powder processed with blanching and drying of raw material were four named RH(not blanched, hot air dried), RF(not blanched, freeze dried), BH(blanched, hot air dried) and BF(blanched, freeze dried). Blanching affected the reduction of drying time in chestnut. Water absorption index of the blanched samples were higher than the nonblanched. Blanching affected the viscosity of pastes when water was added to process paste also, but drying methods did not affected to it. The proper ratio of water to the powder to process paste was 1.3 to 1.5 times in RH and RF, whereas 2.7 times in BH and BF by sensory evaluation. Soluble tannin content of paste was higher in RF and RH paste than BF and BH. Vitamin C content was the highest(88.49mg/100g) in RF paste and reducing sugar content was the highest in RF paste. Hunter's L and a values were the highest in BF and RH pastes, respectively, among the all paste samples. Volatile compounds detected from chestnutpastes were hydrocarbons, alcohols, phenols, ketones. The major volatile compound in all the pastes was 2,6 bis(1,1 dimethylethyl) 4 methyl phenol.

• Journal of the Korean Society of Food Culture
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• v.5 no.2
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• pp.229-233
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• 1990

Changes in chemical components of green tea leaves at different cooking conditions-blanching and frying-were surveyed as a method of utilizing low graded green tea leaves which missed appropriate plucking times. There was no significant difference in protein content during cooking. But contents of chlorophyll, tannin, vitamin C and caffeine were decreased during cooking, contents of chlorophyll and caffeine showed a greater decrease in frying than blanching. Content of total amino acid of green tea leaf was 15.8% and blanching showed bigger diminution of its content in comparision with frying during cooking.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.246-253
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• 2012

In this study, we determined the optimum blanching conditions for pretreatment of Aster scaber prior to freezing to ensure its long, safe preservation as a fine cooking ingredient. Frozen-thawed A. scaber did not significantly differ between blanching groups, but the blanched group showed significantly higher Hunter L, a, and b values than the un-blanched group (p<0.05). Higher temperatures and longer treatment times increased softness; hardness did not significantly differ between the blanched and un-blanched groups of frozen-thawed A. scaber (p<0.05). Total bacterial counts and the presence of coliforms seemed to decline with blanching treatments, but treatment temperature and time did not influence this reduction. Over 95% of peroxidase activity was inactivated by blanching treatment but increased slightly after thawing. The sensory evaluation of the frozen-thawed A. scaber by test group showed the A. scaber blanched at $90^{\circ}C$ for 3 min to be the most highly preferred (p<0.05).

• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.190-194
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• 2005

This study was conducted to investigate the changes in contents of total flavonoid and total polyphenol of three leafy vegetables, spinach(Spinacia oleracea L.), chard(Beta vulgaris L.), whorled mallow(Malva verticillata L.) by various blanching times. Total flavonoid and total polyphenol contents of spinach were 21.01 and 25.58 mg/g, those of chard were 26.02 and 35.14 mg/g, and those of whorled mallow were 16.80 and 19.94 mg/g, respectively. Total flavonoid and total polyphenol contents of chard were the highest among the leafy vegetables. Total flavonoid and total polyphenol contents of leafy vegetables were decreased according to blanching time. Especially, total flavonoid content of chard showed significant loss of $15-30\%$ by blanching time. Total polyphenol content of whorled mallow showed loss of $37-39\%$, but the decrease was not significant.

• Food Science and Preservation
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• v.18 no.5
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• pp.661-668
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• 2011

This study was conducted to devise appropriate blanching-process conditions as a means to convert Doraji, which is widely used in Korean food due to its unique fragrance and flavor, into frozen food materials for various uses. For the Hunter L values representing the brightness transformation among the surface color and gloss changes that were observed in Doraji before and after freezing, and after Doraji went through a blanching process, the specimen that went through a blanching process at $80^{\circ}C$ showed a significantly higher value compared to another specimen processed at a higher temperature, and the first specimen's value also rose after freezing. Meanwhile, for the hardness values, they declined more as the blanching temperature became higher and as the processing time became longer. For the number of total counts and the number of coliform groups, the number of total counts at $3.75{\times}10^5$ and $1.25{\times}10^5$ cfu/g before the blanching process was reduced into the approximately 2-3 log scale, and no coliform group was detected after the blanching process. As for the peroxidase activity, its activation was decreased by the blanching process, and more than 89% of the peroxidase became inactivated in all the specimens that went through the blanching process. The sensory characteristics of the frozen-thawed Doraji by test group showed the radish leaves blanched at $90^{\circ}C$ for 1 min to be the most highly evaluated in terms of the overall preference level (p<0.05).

• Food Science and Preservation
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• v.21 no.5
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• pp.694-701
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• 2014

The quality characteristics of blanched Aster scaber with the blanching condition and various solutes (non-treated, NT; soluble Ca, SC; sodium bicarbonate, SB; and magnesium sulfate, MS) were evaluated with different blanching times and solutes. The blanching process decreased the total polyphenolics, ascorbic acid contents, hardness, and cutting strength of the leaves. As for the pectinesterase and polygalacturonase, the blanching process increased their inhibitory activities, and more than 90% of them were inactivated in all the samples that were blanched. For the total counts and the number of coliform groups, the number of total aerobes at 5.92-log CFU/g before the blanching process was reduced to the approximately 2-3 log scale, and the coliform group was not detected after the blanching. The blanching also significantly decreased the total chlorophyll a and b ratios. The sensory characteristics of the Aster scaber according to the test group showed that the leaves blanched for 3 min were the most highly evaluated in terms of their overall acceptability. The phenolic compound, chlorophyll, and carotenoid contents tended to increase from before their blanching, and the Ca/Cb ratio was higher in the SC. These results showed that SC and MS treatment had greater effects on the quality characteristics and the pigmentation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.827-835
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• 2022

Commercial boiled frozen ark shell Scapharca subcrenata (BFAS) is generally used as a seasoned seafood products. One problem facing the industry is that quality decreases during thawing. This study investigated ways to improve quality and shelf-stability of BFAS for use as a non-thermally prepared seasoned seafood products. The Viable bacteria were detected in BFAS after thawing under running water, but were not detected after blanching for over 2 min at 95±5℃. Blanching and dewatering times were optimized by response surface methodology (RSM) to reduce the initial number of bacteria and improve BFAS texture. Experimental design was deemed appropriate because no significant difference (P>0.05) was observed between predicted and actual moisture content, hardness, and overall acceptance values. Optimal blanching and dewatering times were 210 s and 80 s, respectively. Optimized blanching and dewatering processes can significantly improve safety and BAFS qualities including texture. These results indicate that BFAS demand as a staple for home meal replacements can be increased by application of optimized blanching and dewatering processes, especially in Korean seafood processing companies where running water thawing is common.