• The Korean Journal of Food And Nutrition
• /
• v.31 no.2
• /
• pp.229-235
• /
• 2018

Ramie (Boehmeria nivea M.) has been used for fiber materials in Korea traditionally, but in recent years, the concern with ramie leaves for the food industry such as tteok (a kind of Korean rice cake) industry has been increasing, so a study for eatable ramie is required for the expansion of ramie consumption. Moreover, the ramie varieties for the food industry are not established, so the natural species are cultivated in general; therefore, it is very important to select the ramie varieties for the food industry such as rice cakes, tea, beverage and so on. This study was undertaken to compare the physiochemical properties among 9 ramie lines selected in the Yeonggwang-gun Agricultural Technology Center to select the eatable ramie varieties for the food industry. The contents of the protein among 9 ramie lines was 6.21~7.56% and had the highest content in the YG55. The folic acid (folate) and vitamin C content had varying differences among the 9 lines; the content of folate showed $771.52{\sim}1,978.84{\mu}g%$, that of vitamin C showed 149.42~275.34 mg%. The ACE inhibitory activity appeared to be the highest in YG88 (21.5%) among the 9 ramie varieties tested.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.5
• /
• pp.752-757
• /
• 1995

The effect of fermentation temperature on the changes of pH, acidity, salt content, color and vitamin C of mustard leaf kimchi during various storage days was investigated. The conditions of fermentation temperature were set at $4^{\circ}C$ (sample A) and $20^{\circ}C$ (sample B), and $4^{\circ}C$ after keeping at $20^{\circ}C$ for 12 hours(sample C) and $20^{\circ}C$ for 36 hours(sample D). As the fermentation proceeded, pH of sample stored at low temperature(sample A) was drop ped gradually from initial pH of 5.24 but there was great pH drop in the sample stored at high temperature(sample B, D). The salt content of the sample B at high temperature increased remarkably, and then the values showed D > A > C. The Humter values of L and a increased at the optimum ripening period, the higher the initial fermentation temperature(B) and the later the initial fermentation time at $20^{\circ}C$ those values, then decreased. The Hunter value of b constantly increased until day of 108. As fermentation time passed, the content of total vitamin C decreased to the range of 9.0mg% to 14.0mg% up to 24 days of fermentation, and at the optimum ripening period, it increased to the range of 14.0mg% to 22.0mg%, and at the fermentation period(until day 108), it decreased gradually.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.48 no.6
• /
• pp.876-882
• /
• 2015

The aim of this study was to investigate changes in the biochemical characteristics of the Pacific oyster Crassostrea gigas in response to boiling water bath ($85^{\circ}C$, $100^{\circ}C$) and autoclaving ($100^{\circ}C$) heat treatments for 5, 10, 15, and 20 min. The weight loss (7.6-9.5%) of oysters exposed to a $100^{\circ}C$ boiling water bath for 15 min was lower compared to those receiving no treatment. Oysters exposed to the $100^{\circ}C$ boiling water bath for 20 min lost 27.8% of their total weight. The $100^{\circ}C$ autoclaving treatment resulted in weight loss of 13.0-26.1%, with the highest weight loss occurring after 10 min of treatment (26.1%). Heat-treated oysters had significantly higher levels of crude lipid and crude protein relative to untreated oysters (P<0.05). In the heat-treated oysters, total amino acids (including proline and glutamic acid) were increased, but they were decreased by the 20-min $100^{\circ}C$ boiling water bath and autoclaving treatments. The fatty acid composition of oysters was not significantly affected by the water bath heat treatment, but oysters treated with $100^{\circ}C$ autoclaving for 20 min had decreased polyunsaturated fatty acids. Oysters exposed to the water bath heat treatment had significantly increased vitamin A content, but $100^{\circ}C$ autoclaving for 20 min was associated with reduced vitamin A content, as compared to all of the other heat treatments. Therefore, oysters were affected by heat treatment, undergoing metamorphosis and weight loss, but nutrient quality did not change significantly compared to controls, except with the 20-min $100^{\circ}C$ boiling water bath and autoclaving treatments.

• Korean Journal of Food Science and Technology
• /
• v.18 no.3
• /
• pp.187-191
• /
• 1986

Vitamin retention in rice bran during the extrusion cooking adapted for the rice bran stabilization was studied. The rice bran of different moisture content (9.5% and 15.6%) were extruded with cooking extruder (screw dia: 100mm. strew rpm:900. L/D ratio: 10.0) under the given conditions of specific power consumption(42.1 67.9 W/Kg) and extrusion temperatures $(99-135^{\circ}C)$. The affected retention rates of thiamine, riboflavin and niacin in extruded rice bran were determined. The extruded rice bran with higher moisture level had a lower or similar vitamin retention rate at lower specific power consumption and extrusion temperatures, relatively. The vitamin retention in extruded rice brail with the same moisture level were gradually decreased by the increased specific politer consumption and extrusion temperatures. The vitamin retention of rice bran during the extrusion cooking for the rice bran stabilization were observed as 89.9-97.0% for thiamin, 83.4- 97.3% for riboflavin and 94.0 - 97.7% for niacin, respectively.

• Korean Journal of Community Nutrition
• /
• v.23 no.2
• /
• pp.93-101
• /
• 2018

Objectives: With the increasing number of single households and so-called Honbab-jok, those who eat alone, people tend to enjoy convenient and simple meals, such as single dish meals. This study was performed to provide data on the energy and nutrient content, and nutritional adequacy of single-dish meal. Methods: From the literature reviews, 61 types of single-dish meals were selected, and divided into 4 groups (steamed rice, noodle, porridge, and sandwich burger), and a further 11 sub-groups (bibimbab, fried rice, topped rice, rolled rice/ warm noodle, cold noodle, seasoned noodle, dukgook/ porridge/, and sandwich, burger). In addition, 382 junior high school students from Gyeonggi, Sejong, Jeonbuk, and Chungnam areas were recruited for the survey. The survey questionnaires were composed of the characteristics, preference, and intake frequency of single-dish meals. The representative energy content (arithmetic mean) of single-dish meals were calculated, and compared with the energy contents of preference and intake frequency-weighted values adjusted. The representative nutrient contents, energy contribution ratio, and INQ (index of nutritional quality) of a single-dish meal were calculated for a nutritional adequacy evaluation. Results: The study subjects considered a single-dish meal as tasty, simple and fast to prepare, inexpensive, nutritious, and no low calorie food. The preference scores of all but 1 sub-group of singledish meals were ${\geq}5.00$ (5.00~5.97), and 1 sub-group (porridge) was 4.67 on a 7-point scale. The intake frequency of 11 sub-groups were 0.31~1.71/week, porridge was the lowest at 0.31 and warm noodles was the highest at 1.71. Fried rice, rolled rice, and warm noodle' intake frequency were ${\geq}1/week$. The representative energy of steamed rice, noodle, sandwich burger were 443, 429, and 428 kcal, respectively, and that of porridge was 264 kcal. Less than 5% differences in the representative energy of 4 groups were observed when adjusted for the preference or intake frequency-weighted values. The energy contribution ratio of macro-nutrients calculations showed that porridge was a high carbohydrate and low fat food, whereas sandwich burger were high fat and low carbohydrate foods. The INQ of calcium and vitamin C were less than 1.0 in all 4 food groups, but the INQ of protein and thiamin were > 1.0 in all 4 single-dish food groups. Conclusions: The representative energy in the 4 groups of single-dish meal was 264~450 kcal, which is a rather low calorie meal, and the energy contribution ratio of macro-nutrients were inadequate. The protein and thiamin levels were sufficient but the calcium and vitamin C levels were insufficient in all 4 groups of a single-dish meal judged by the INQ. The additional intake of fruits and milk dairy products between meals with a single-dish meal, supply of calcium and vitamin C may increase, which will result in an improved nutritional balance.

• Korean Journal of Food Science and Technology
• /
• v.26 no.4
• /
• pp.471-474
• /
• 1994

Growing barley leaves with $20{\sim}50cm$ length were analyzed for chemical constituents including moisture, crude fiber, protein, fat, ash, free sugars, free amino acids, chlorophylls, vitamin C and minerals. During the growth of barley leaves, moisture content decreased, while crude fiber gradually increased. Protein, fat and ash contents of barley leaves remained relatively unchanged. Chlorophyll content increased to a maximum value at the leaf length of 20 cm, and then declined. Minerals of barley leaves were abundant in the following order of K>Ca>P>Na>Mg. Vitamin C content, showing the similar trend to chlorophyll, was the highest at the leaf length of 20 cm. Major free sugars present in growing barley leaves were identified as glucose, fructose and sucrose. All the free sugars reached their maximum values at 20 cm and they were reduced thereafter. Total amount of free amino acids varied from 803 mg% at the Barley stage of l0 cm to 1038 mg% at the later stage of 50 cm. Changes in content for each amino acid were variable to some extent.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.9
• /
• pp.1316-1323
• /
• 2016

The aim of this study was to evaluate proteolytic and antioxidant activities of fresh pineapple and kiwi juices extracted using a slow-speed masticating household juicer during low temperature storage. While over 90% of vitamin C and total polyphenols in both juices were retained after storage for 30 days at $-20^{\circ}C$, reduction of 56.8% for vitamin C and 31.9% for total polyphenols in pineapple juice were detected after storage at $4^{\circ}C$. In the case of kiwi juice, 32.9% of vitamin C and 22.4% of total polyphenols were lost. A high initial content of vitamin C in kiwi juice resulted in a slower reduction rate than that for pineapple juice. A similar result was obtained for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Proteolytic activities of both juices were maintained efficiently with less than 10% loss during storage for 30 days at $-20^{\circ}C$. Protease stability of pineapple juice was better than that of kiwi juice during storage at $4^{\circ}C$, and the same result was obtained when boiled chicken breast was used as a substrate. From these results, when storing pineapple and kiwi juices, which are widely used as a natural meat tenderizer and digestive aid, cold storage at $-20^{\circ}C$ seemed to be more suitable for maintaining antioxidant and proteolytic activities than cold storage at $4^{\circ}C$.

• Korean Journal of Human Ecology
• /
• v.3 no.1
• /
• pp.51-58
• /
• 1994

The rapid development of science and technology has brought about a quantitative expansion and a decrease of practical life span of information. Food science, a kind of life science and practical science, can not be an exception. Analysis of food components is the fundamental basis of the Food Science. So I would like this to be of some help to the following researches through the quantitative and qualitative analysis of the contents of the food analysis research papers in food science related Korean journals. Five hundred seventy four research papers published from 1984 to 1993 in the three journals, that is, Korean Journal of Food Science & Technology. The Korean Journal of Nutrition, The Korean Journal of Home Economics, which is three major journals read by people in Home Economics area are analyzed in this study. The method applied in this study is content analysis. Followings are the results of the content analysis : 1) When categorize the material foods into food groups, cereal group is analyzed most often(15.8%), followed by fish and shellfish group(12.4%), oil and fat group(11.8%). The least often analyzed food group is egg group. Among the food soybean is most often analyzed(6.0%), followed by polished rice(3.7%), glutinous rice(2.2%), cabbage(2.1%) and human milk(1.8%). 2) About the analyzed food components, the general components such as moisture, crude protein, crude fat, carbohydrate and ash has been analyzed very often but the trace nutrients such as vitamins and minerals has scarcely been analyzed. 3) The method used in the food components analysis is usually AOAC(Association of Official Analytical Chemist, USA). HPLC was applied to the analysis of many food components like amino acids, fatty acids, vitamin A, thiamin, riboflavin, niacin, vitamin C and vitamin E.

• Korean Journal of Medicinal Crop Science
• /
• v.9 no.1
• /
• pp.40-44
• /
• 2001

DPPH(1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity and Vitamin contents in different plant parts and harvesting time of Rosa rugosa Thunb were determined. Among the plants parts analysed, the highest DPPH radical scavenging activity in part was root $(below\;0.5\;{\mu}g/ml)$, leaf contained the highest ascorbic acid content of 2999.6 mg/100g. Fruit contained ascorbic acid (713.6 mg/ 100g) 4.2 times less than leaf. Vitamin contents in leaf parts also differed depanding on harvesting time. Vitamin content in leaf harvested in November was much higher than that in September. Spectrophotometric analysis of total ${\beta}-carotene$ in leaf showed lower contents than that in fruit.

• Journal of Bio-Environment Control
• /
• v.11 no.4
• /
• pp.199-204
• /
• 2002

To overcome a decrease of Korean ginseng production caused by successive cropping, we have tried to develop a nutrient culture system for Korean ginseng production. For determining the optimal substrate, mixture of sand and TKS-2 (S＋T), peatmoss (P), reused rockwool (RR), and granular rockwool (GR) were investigated. The overall physico-chemical properties of RR fell into the reported optimal range for the ginseng cultivation. However, bulk density of S＋T was a little higher than that of soil in Korean ginseng fields. The top fresh weight of the ginseng was high in RR and S＋T substrates. The root fresh and dry weights in the RR were remarkably greater than that in the conventional soil (CS) of Korean ginseng fields. In terms of ginseng quality, the vitamin C content of ginseng root in nutrient culture was higher than that in CS. However, the contents of crude saponin and total ginsenosides in ginseng between in the nutrient culture and in the soil culture did not show any significant differences.