• Journal of the East Asian Society of Dietary Life
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• v.22 no.2
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• pp.190-198
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• 2012

This research evaluated and analyzed the level of acceptability of spinach according to blanching time by testing consumer taste of corresponding countries for the purpose of globalizing Korean food. General taste, appearance, flavor, and texture of spinach blanched for 20 seconds were highly evaluated by Koreans and Japanese ($p$<0.05), who are used to the method of slightly blanching, mixing, and eating spinach. On the other hand, general taste, appearance, flavor, and texture of spinach blanched for 5 minutes was highly evaluated by the French ($p$<0.05), who are used to eating boiled spinach. Concerning the result of JAR, there were clear differences in hardness and boiling level according to country among spinach samples, even though they were blanched for the same time and mixed with the same spices. Koreans and Japanese evaluated that hardness and boiling level of spinach blanched for 20 seconds were proper, whereas the French evaluated that spinach scalded for 20 seconds was too raw and crispy. Under the same context, French consumers evaluated that hardness and boiling level of spinach blanched for 5 minutes was proper, whereas Koreans and Japanese evaluated that spinach blanched for 5 minutes was boiled too much. These results show that familiarity level is an important driver of affecting the preference levels for three kinds of spinach according to country.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.990-995
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• 2016

In the present study, reversed-phase HPLC was utilized to quantify the ${\beta}$-carotene content of 22 kinds of raw and blanched vegetables consumed in Korea. In addition, true retention (TR) of ${\beta}$-carotene in samples was obtained. For quantification of ${\beta}$-carotene, external standard curve was obtained with limit of detection and limit of quantitation. The ${\beta}$-carotene contents in 22 raw vegetables ranged from 6.29 (bellflower root) to $7,050.73{\mu}g/100g$ (spinach, field culture). After blanching, ${\beta}$-carotene contents of 13 vegetables increased up to 103.05% while nine vegetables resulted in reduced content, ranging from -2.17 to -29.16%. However, even though increased ${\beta}$-carotene content was observed after blanching, TR of some vegetables was lower than 100% due to their weight reduction. The highest TR of ${\beta}$-carotene was found from blanched cabbage (164.46%) while the lowest TR was found from Turcz (Gomchwi) at 59.35%. TR is an effective method to evaluate retention of nutrients in cooked foods, considering changes of nutrient content and weight.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.857-863
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• 2012

This study prepares dried sweet pumpkins to optimize pretreatment conditions of blanching, steaming and microwave heating and to investigate the quality characteristic of each method. The sweet pumpkin blanching treatment of moisture content decreased gradually with increasing temperature, and soluble solids, and weight loss was increased. Color temperature is lower, and a higher value of L value and b value increased. As for the sweet pumpkin steaming treatment of moisture content, it was observed that the longer the steaming time was decreased, sugar content was increased. Change of color in the L value, the longer the steaming time a and b values. Also, as for the microwave treatment of the sweet pumpkin, the longer the time the moisture content decreased, it slightly increased soluble solids and weight loss. Blanching showed the lowest hardness of texture, followed by steaming, and microwaves, in order. Penetration per 20 hours per type was determined by sensory evaluation of sugar, and sugar:fructose(1:2)ratio were higher in the composition.

• Food Science and Preservation
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• v.22 no.1
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• pp.44-50
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• 2015

This study was performed to optimize the preparation of frozen lotus roots. Prior to freezing, an optimal blanching condition at $100^{\circ}C$ for 5 min was established, based on the microbial growth, texture, total phenolic content (TPC), and sensory evaluation results. The blanched samples were then frozen under various freezing conditions ($-20^{\circ}C$ in a freezer for 2 hr, $-70^{\circ}C$ in a gas nitrogen convection chamber for 7 min, and $-196^{\circ}C$ in liquid nitrogen for 20 sec), and their qualities after thawing were determined. The scanning electron microscopic analysis indicated that the microstructure of the sample frozen at $-70^{\circ}C$ was similar to that of the control sample, compared with the other freezing conditions (-20 and $-196^{\circ}C$). The antioxidant activities of the frozen samples decreased compared to those of the control, but there was no significant (p<0.05) difference among the treatments. In terms of TPC, the samples frozen at -70 and $-196^{\circ}C$ had significantly (p<0.05) higher values than the sample frozen at $-20^{\circ}C$. In addition, the drip loss of the sample frozen at $-20^{\circ}C$ was higher than those of the other frozen samples. These results suggest that freezing at $-70^{\circ}C$ in a gas nitrogen convection chamber can be an optimal freezing method of producing high-quality frozen lotus roots.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.184-190
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• 2015

We evaluated the effects of three common cabbage cooking methods (blanching, steaming and microwaving) on glucosinolate and S-methylmethionine (SMM) content and total antioxidant capacity of cabbage leaves. We detected four glucosinolates, including glucoraphanin, sinigrin, glucobrassicin, and 4-methoxyglucobrassicin, by high-pressure liquid chromatography (HPLC). Cabbage contained high levels of SMM (192.85 mg/100 g dry weight), compared to other cruciferous vegetables. Blanching cabbage leaves for one to ten minutes decreased glucosinolate and SMM levels, whereas microwaving or steaming cabbage for 5-10 min preserved glucosinolate and SMM levels. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2-2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activities of cooked cabbage generally decreased as cooking time increased, but microwave cooking had a smaller negative effect on antioxidant activities than blanching or steaming. This study demonstrates that some domestic cooking methods, such as microwaving and steaming, can increase the bioaccessibility of glucosinolates and SMM, highlighting the positive role of cooking on the nutritional qualities of cabbage.

• Korean journal of food and cookery science
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• v.18 no.4
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• pp.461-469
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• 2002

In order to develop a better food preparation method in terms of vitamin retention in food service establishments, the retention rate of riboflavin in two kinds of Korean dish (stir-fried sausage with vegetables, stir-fried garlic young stems) were examined during various cooking stages, holding temperature and duration time. Riboflavin content of the sample was analyzed using by using a HPLC with a fluorescent detector at various holding durations and temperatures. Also the changes in the pH and water contents of the samples were measured during holding at various temperatures to find any relation among the pH, water contents and riboflavin content. In the results, there were significant differences in riboflavin contents at various cooking processes such as washing, slicing, blanching, soaking, etc. Also, the retention rates of riboflavin at various holding methods and temperature were significantly different from one another. Especially 50% reduction of riboflavin content occurred during blanching of young garlic stem and only 38% of riboflavin was left after slicing carrots for stir-frying of sausage.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.555-561
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• 2003

The purpose of this study was to analyze the microbiological hazards of dried fish (Jwieochae, Ojingeochae and Bugeochae), and to apply pretreatment methods to increase the safety of cooked dried fish within foodservice establishments. Microbiological inspections were conducted on Total Plate Count, Coliforms, E. coli, E. coli O157:H7, Staphylococcus aureus, Salmonella spp. and Listeria monocytogenes. The study results are summarized as follows. According to the Hazard analysis, there are many problems showing high numbers in terms of Total Plate Count and Coliforms, which were both well over acceptable standard levels. E. coli and Staphylococcus aureus were detected at certain foodservice establishments, while E. coli O157:H7, Salmonella spp. and Listeria monocytogenes were not detected at all. By applying various pretreatment methods, such as washing, blanching, pan frying and microwave heating, the levels of microbiological hazards were able to be controlled and lowered. Blanching was the most effective method, followed by panfrying, microwave heating and washing. The Total Plate Counts gradually decreased with increasing number of times washed and seconds panfried. From these results, it is concluded that to guarantee food safety, cooked dried fish raw materials should be kept hygienically and appropriate pretreatment methods applied before cooking.

• Korean journal of food and cookery science
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• v.32 no.3
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• pp.245-252
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• 2016

Purpose: To provide the public with nutritional information on consumption types of garlic, we evaluated the influence of heat treatment method on the nutritional contents of different species of garlic. Methods: We determined the content of general components, minerals, vitamins, and fatty acids in each species of garlic produced in Seosan and Goheung by heating with blanching or microwave roasting. Results: The results of the two-way analysis of variance test indicated that the species in particular, as well as method of heat treatment and interaction, had an influence on nutritional content. The moisture and crude fat content was higher in Southern type garlic than in Northern type garlic, while crude proteins, crude ash, and dietary fibers were more abundant in Northern type garlic than in Southern type garlic. With regard to the total mineral content, K, P, Mg, and Ca were the main components in Northern type garlic and Southern type garlic. Moreover, unsaturated fatty acids showed high levels in both Northern type garlic and Southern type garlic, with more abundant linoleic acid. Overall, Northern type garlic showed a higher content of minerals and fatty acids, while more vitamin B was present in Southern type garlic. In addition, the results indicated that the content of general components (dietary fiber excluded) was increased in both Northern type garlic and Southern type garlic upon heat treatment. Blanching resulted in increased mineral and fatty acid content in Southern type garlic and decreased content in Northern type garlic, indicative of species differences; conversely, microwave roasting contributed to an increase in the content in both Northern type garlic and Southern type garlic. Conclusion: The nutritional content of garlic is more dependent on species than the cooking method, and grilling is associated with less nutrient loss than blanching.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.159-163
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• 2013

As mulberry fruit's functionalities are known to the media, the interest in promoting of consumption and processed products is increasing. But there is no C3G(Cyanidin-3-glucoside) data based on the stability of the pigment during processing. To solve this problems, and to expand the use of mulberry fruit, processing methods was developed for mulberry fruit juice improved cyanidin-3-glucoside(C3G) stability. The results obtained are summarized as follows. The food additive citric acid with 0.3 % improved C3G content and antioxidant ability in the treatment of mulberry fruit and sucrose the ratio of 50 % : 50 %(w/w). In the case of the addition of oligosaccharides, citric acid decreased antioxidant ability. Xylitol treatment showed up the lowest of C3 content, but by the addition of citric acid improved the pigment content and antioxidant activity of the mulberry fruit juice. Addition of citric acid was more affected C3G stability than containers (clear glass bottles, brown glass bottles, aluminum foil, green glass bottle, translucent glass bottles). In the processing of mulberry juice, 3 minutes blanching treatment using microwave dropped C3G content somewhat. Therefore, using this method is not recommended. However in the antioxidant ability, microwave blanching showed a stabilizing effect compared to the other treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.399-405
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• 2010

After Gomchui tea was prepared from leaves of Ligularia fischeri (Ledeb.) Turcz by blanching method, the antioxidant activity of major compounds in Gomchui tea was assessed. On-line HPLC-ABTS analysis revealed that caffeoylquinic acids (chlorogenic acids), such as 5-O-caffeoylquinic acid (5-CQA), 3,4-di-O-caffeoylquinic acid (3,4-DCQA), 3,5-di-O-caffeoylquinic acid (3,5-DCQA) and 4,5-di-O-caffeoylquinic acid (4,5-DCQA), were the major antioxidant compounds in Gomchui tea. The extraction efficiency of these compounds were examined in the various conditions such as extraction temperature, time and solvent. The results demonstrated that the extraction amount with water increased in proportion to extraction time (1~10 min) and temperature ($8{\sim}80^{\circ}C$). These active compounds were also extracted with water even at $8^{\circ}C$ (60% of $80^{\circ}C$), indicating that water is very good extraction solvent for extraction of these antioxidant constituents. However, the extraction efficiency of these compounds decreased when ethanol percentage in water increased. The extraction efficiency between Gomchui powder (no blanching) and tea was significantly different, and 60% of total antioxidant compounds in tea was removed from fresh leaves into water in blanching process, especially 3,5-DCQA (over 90%). Meanwhile, the sonication method didn't affect the extraction of these compounds in all solvents. These results suggest that Gomchui tea can be a good candidate for the tea beneficial to human health.