• Journal of the Korean Society of Food Culture
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• v.37 no.6
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• pp.540-546
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• 2022

This study aimed to determine the changes in the vitamin B₅ content of raw and cooked vegetables. The nineteen vegetables were subjected to different cooking methods, viz. blanching, boiling, pan-broiling, and steaming. Vitamin B₅ was quantified by reversed-phase high-performance liquid chromatography (HPLC) using photodiode-array (PDA) detection (200 nm). The standard reference materials (SRM) were used to validate the accuracy of vitamin B₅ measurement method used in this study. The cooking yields ranged from 82.63 to 107.62% and decreased in most of the vegetables except bitter melon, curled mallow, and eggplant. The raw kabocha squash, Danhobak, had the highest vitamin B₅ content (0.671 mg/100 g) among the samples. All cooked vegetables showed lower vitamin B₅ content compared to the raw samples. The true retention ranged from 0% (crown daisy, blanching) to 84.49% (kabocha squash, steaming). These results indicate that vitamin B₅ is degraded after cooking. Pan-broiling and steaming are better cooking methods than the others for retaining vitamin B₅. The true retention of vitamin B₅ in the samples markedly depends on the cooking method and food matrix. These results can be used as important basic data for nutritional evaluation of meals.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.147-152
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• 1999

HPLC was used for determining polyphenols which are known as the functional compounds in the unripe apples Fuji and Aori. The changes in their contents caused by heat treatments were monitored. The carbohydrate contents in Fuji and Aori were 14.1% and 13.5% respectively. Both apple juices showed pH 3.2 and $8.0\;brix^{\circ}$, which were relatively low levels. The major polyphenols were composed of (+)-catechin, chlorogenic acid, (-)-epicatechin, and tannic acid. Total polyphenol contents in Fuji and Aori were 0.11, 0.12% by Folin-Denis method. HPLC analysis of polyphenols showed that four major components were contained by 0.06% in Fuji and 0.07% in Aori. Chlorogenic acid was three times higher in Fuji than in Aori. After water blanching, the area percent of polyphenols resulted in an increase by 3.54% in Fuji but a decrease by 2.93% in Aori. Pasteurization of juices led to decrease by 1.39% and 3.31% respectively. Blanching and pasteurization of unripe apple juices induced negligible changes in polyphenol contents during storage. During concentration, polyphenol contents increased in proportion to the concentration of unripe apple juices.

• Korean journal of food and cookery science
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• v.11 no.1
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• pp.44-50
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• 1995

In order to investigate the mechanical and sensory characteristics of dried Lentinus edodes, raw Lentinus edodes, Pleurotus ostreatus and Agaricus bisporus by various cooking methods, texture measurements and sensory evaluation were performed. And the results were summarised as follows. Hardness, cohesiveness, springiness, gumminess and chewiness of those mushrooms, except the cohesiveness and springiness of Pleurotus ostreatus head, showed significant differences depending on the cooking methods. Microwave heating of mushrooms, in general, give high values in mechanical characteristics measurements. As a results of sensory evaluation, salt water blanching turned out to be the most preferred cooking method among blanching, steaming, microwave heating. The mushroom dishes were preferred by the panel in the order of Jungol, Hoi, Fritter, Saute and Jun.

• Culinary science and hospitality research
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• v.23 no.7
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• pp.220-233
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• 2017

The purposes of this study were: (1) to examine the quality characteristics of the Sulgidducks added with barley sprouts by blanching (CON), freeze-drying (FBP), hot-air drying(HBP); (2) to examine the quality characteristics of Sulgidduck such as the moisture content, the color value, the textural properties and the sensory evaluation; (3) to find the optimal ratio of barley sprouts, which were made by the three different drying methods. As a result, the Sulgidduks containing barley sprouts by CON showed a lot of significance and high correlation depending on the amounts of the barley sprout(p<0.05). As the amounts of CON, FBP and HBP increased, the L and the a values of Sulgidducks significantly decreased, whereas the b values of them increased. For the textual properties of the Sulgidducks, on the first day, the concentration in CON up to 6% showed no significant differences in the hardness, cohesiveness, springiness, and chewiness. In case of FBP, the increase in the additives caused decrease in the hardness, adhesiveness, springiness, and chewiness of the Sulgidducks on storage 0 day(p<0.05). As the amounts of HBP increased, the hardness, springiness of the Sulgidducks on the first day decreased(p<0.05). Conclusionally, 6% blanched barley sprout added group, 2% FBP and HBP were highly rated in color, flavor, bitterness, chewiness, overall acceptability and all sensory quality characteristics.

• Korean journal of food and cookery science
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• v.32 no.3
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• pp.270-278
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• 2016

Purpose: We have investigated for the purpose of studying change of vitamins and minerals in frequently used vegetables by low moisture cooking method. Methods: Vitamin B complex, vitamin C and mineral (Mg, Ca, K, Zn, Fe) contents are analyzed in vegetables such as spinach, cabbage, bean sprouts and carrot which are heat-treated with degrees of water contents. Low moisture cooking method represents heat-treated vegetable (LM experiment group) with 25 wt.% water content for the vegetable weight while general blanching method includes heat-treated vegetable (GB experiment group) with 500-1,000 wt.% water content for the vegetable weight. Results: Retention rate of vitamin B1 (thiamin) in the LM experiment group is relatively high (87.50-95.68%) and dosen't show considerable differences from raw vegetables. On the other hand, the retention rate of vitamin $B_1$ in GB group's cabbage and spinach dramatically decreased to 19.46-25.00%. Retention rate of vitamin B2 (riboflavin) is sustained stably in LM experiment group (75.00-87.50% in bean sprouts, cabbage and spinach), represents that low moisture cooking method has relatively higher contents in vitamin $B_2$. The LM experiment group has 71.43-85.71% on retention rate of niacin while the GB group shows relatively lower niacin (57.14-64.58%), represents conflicting results from the general idea that vitamin $B_3$ is relatively stable in heat treatment and blanching. Retention rate of pantothenic acid is considerably higher in both LM and GB experiment group, indicates vitamin pantothenic acid is relatively stable in the various cooking condition such as amount of water and heat treatment. In the experiment under various water contents, vitamin C is not detected in both bean sprouts and carrots, while the contents in cabbage and spinach are 19.87 mg/100 g and 26.65 mg/100 g respectively. In the same experiment, the retention rate of Vitamin C in LM experiment group (91.65%, 92.23%) is considerably higher than GB group (58.08%, 61.61%). Retention rate of Mg, K, Fe in the LM experiment group is relatively higher than GB group. Conclusion: Resultingly, the observations suggests that minimum water quantity and minimum heat treatment processes should be established in cooking vegetables which have soluble vitamins and minerals.

• Culinary science and hospitality research
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• v.12 no.1 s.28
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• pp.93-110
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• 2006

Eumsik-dimibang is the oldest and first cooking recipe book in Korean language ever published in Korea. It was examined in order to find out food ingredients being used as side dishes and its cooking methods used at that time. As side dishes, there were many foods which used dogs as food ingredients for making Gae Jang Jim and Gae Jang etc. as well as Dong A such as Dong A Nurumi and Dong A sun. Also, there were many foods prepared by Nurumi cooking method for making Gae Jang Guk, Nurumi, eggplant Nurumi etc. From cooking methods for food ingredients for side dishes at that time, following characteristics could be found. First, there was a cooking method of broiling meat on fire after blanching it in water. Second, many cooking methods were used to remove fetid smells and fishy smells (using ginger, pepper, cheoncho etc). Third, there was a method which demanded much attention and devotion in the course of cooking. Fourth, use and cooking method of flour were diversified.

• Food Science and Preservation
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• v.6 no.1
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• pp.61-65
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• 1999

This study was carried out to investigate change in the components according to drying methods of jujube. Raw jujube was dried with five methods such as sun-drying, hot-air drying after pretreated with sunlight, blanching, microwave treatment, respectively. The contents of soluble sugar and protein in sun-dried jujube were higher than those of other drying methods. The free sugars of dried jujube were consisted of sucrose, glucose and fructose. And the contents of free sugar was not different by drying methods. The major organic acids of dried jujube were oxalic acid, citric acid and malic acid. The contents of glutamic acid, glycine and alanine were higher than those of other amino acids, and the content of each amino acid was not different by drying methods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.393-398
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• 1998

The loss of ascorbic acid in dried red pepper leaves prepare with different drying methods of air-, oven-, microwave oven-, and vacuum drying with blanching or without was determined by a HPLC method. Vacuum drying showed the least loss of ascorbic acid than the other drying methods. Additionally, the feasibility of near infrared reflectance spectroscopy(NIRS) to determine the contents of ascorbic acid in the red pepper leaves was studied. NIRS was found to be an efficient way of determining ascorbic acid contents in red pepper leaves, requiring only 30 seconds of an analytical time.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1310-1315
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• 1999

Polyphenolic compounds widely occurring in the traditional medicine plants have been reported to possess strong antioxidant activity. The antioxidative substances of water soluble extract from leaves, stem bark, root bark and fruit powder of Cudrania tricuspidata were tested in three different in vitro experimental models. In oxidation models using DPPH( , ' diphenyl picrylhydrazyl) method, Fe2+ induced linoleic acid peroxidation, and autooxidation of hepatic microsomal membranes, the antioxidative activities of water soluble extract from stem bark were strong than that from leaves and root bark. Fruits of Cudrania tricuspidata contained the highest amounts of polyphenolic compounds among the parts of this plant. The changes in polyphenolic compound contents of fruit powder caused by heat treatment (20oC, 40oC, and 60oC) were also monitored. After water blanching, contents of phenolic compounds was increased slightly in the following order; 20oC(1454mg), 40oC(1487mg), and 60oC(1511mg). These results supports that water soluble extracts from Cudrania tricuspidata contain antioxidative compounds.

• Food Science and Preservation
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• v.23 no.2
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• pp.204-210
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• 2016

This study aimed to find an effective preservation method of lotus leaves for the preparation of lotus-leaf Yakju throughout the year. The characteristics of Yakju containing lotus leaves pretreated by blanching, steaming, roasting, and drying were investigated in this study. The chemical properties of Yakju (pH, amino acidity, alcohol content, and volatile acid content) were significantly different for all treatments, except for the total acid content. The polyphenol content ranging from 315.89 to 462.63 ppm (p<0.05) was significantly different depending on pretreatment method L color value for Yakju was not significantly different all treatments, while a value was significantly different in Yakju containing frozen stored leaves after pretreatment. The b value was lowest for the blanching treatment, and was significantly different for all treatments. Among the organic acids present in Yakju, the oxalic, citric, and malic acid contents were significantly different for all treatments. In sensory evaluation, lotus-leaf Yakjus containing fresh leaves and dried leaves were preferred to the others in color and flavor among Yakjus prepared with lotus leaves before cold storage. However, among the Yakjus prepared with lotus leaves after cold storage, that containing blanched leaves was preferred to the others in terms of flavor, taste, and overall acceptability.