• Textile Coloration and Finishing
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• v.32 no.4
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• pp.193-198
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• 2020

In this study, the validity of extracts from food waste as biocatalyst for indigo reduction was examined. Dried food wastes such as apple peel and corn waste were water-extracted and freeze-dried. The reducing power of extracts for indigo was evaluated by the oxidation-reduction potential(ORP) measurement of reduction bath and color strength(K/S value) of the fabrics dyed in the indigo reduction bath. Total sugar contents of the apple peel and corn waste extracts were 60.56% and 62.36%, respectively. Antioxidant activity was 64.78% for the extract of apple peel and 7.96% for the extract of corn waste. Indigo reduction took place quickly with both extracts, and maximum color strength was obtained up to 15.91 and 12.11 within 1-3 days, respectively. The oxidation-reduction potential of reduction bath was stabilized in the range of -500 ~ -620 mV according to the kinds of food waste and the extract concentration. At higher concentration of the extracts, reduction power was maintained for longer time and stronger color strength was obtained. Compared to sodium dithionite, the reducing power of the studied extracts was lower, but the reduction stability was superior to it. The studied extracts were effective biocatalyst as biodegradable and safe alternatives to sodium dithionite for indigo reduction.

• Journal of Korean Society on Water Environment
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• v.30 no.5
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• pp.559-567
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• 2014

Since the ocean dumping of organic wastes is prohibited under the London Convention, the need for land treatment of food waste leachate (FWL) has significantly been growing in recent years. This study was conducted to use thermal solubilization to turn FWL into a form that can easily be degraded during the anaerobic digestion process, thereby reducing the percentage of solids and increasing the production of methane. To derive the optimal operating conditions of thermal solubilization, a laboratory-scale reactor was built and operated. The optimal reaction temperature and time turned out to be $190^{\circ}C$ and 90 min, respectively. The BMP test showed a methane production of 465 mL $CH_4/g$ $COD_{Cr}$ and a biodegradation rate of 90.1%. The production of methane rose by about 15%, compared with no the application of thermal solubilization. To reduce the solid content of FWL and improve the methane production, therefore, it may be helpful to apply thermal solubilization to pre-treatment facilities for anaerobic digestion.

• Korean Journal of Community Nutrition
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• v.10 no.4
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• pp.484-492
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• 2005

The purposes of the study were to analyze nutrients of the menus served and to evaluate students' nutrient consumption at school food services. Three middle schools (boys, girls, and co-ed schools) were located in Seoul and Kyunggi Province. A weighed plate method was employed to measure plate wastes and consumption of the menus served. Data was collected for 3 consecutive days at each school. Nutrient analyses for the served and consumed menus were performed using CAN-PRO. On average the students consumed $67\%$ of the menus they were served. By menu category, the students consumed more than $90\%$ of the rice and one-dish foods they were served. Kimchis ($54\%$) and soups/stews ($55\%$) were the menu categories with the lowest consumption rates. The menus served at the boys and coed schools did not meet 1/3 of the recommended daily allowances (RDA) for calcium, iron, and vitamin $B_2$. Due to the plate wastes, the actual consumption of the boys school students did not meet the 1/3 RDA for calories, calcium, iron, vitamin A, vitamin $B_1$ vitamin $B_2$ and niacin. The menus served at the girls school exceeded the 1/3 RDA for all nutrients, but the actual consumption did not meet the 1/3 RDA for calcium, iron, and vitamin $B_2$. During the 3-day periods, the served and consumed menus provided $27\%$ and $24\%$ of energy from fat, which exceeded the recommended proportion of $20\%$. To improve nutrition management at school food services, dietitians should understand factors that influence students' consumption and implement nutrition education programs that emphasize balanced diets.

• Korean journal of food and cookery science
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• v.22 no.4 s.94
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• pp.521-534
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• 2006

The Kimchi intake of elementary students in both school and home is decreasing due to their westernized eating habits which have been affected by the rapid economic growth and industrialization in our modem society. The purposes of this study were to examine the influence of menu selections on the Kimchi intake rate and to provide basic data for an appropriate Kimchi serving size to reduce the plate-waste rate. The results showed that the average daily intake rate of Kimchi of low-grade students was 58.2%, equating to 6${\sim}$18 g, compared to 64.6% for high-grade students, equivalent to 13${\sim}$24 g. Correlation analysis of the intake rate of menu items and Kimchi showed that the Kimchi intake rate increased with increasing total meal intake rate, rice intake rate, soup intake rate, rice mixed with grains intake rate, clear soup intake rate and soybean-paste soup intake rate, but that it decreased as the intake rate of seasoned uncooked vegetables of high-grade students increased. This study is expected to be utilized as a solution to increase the Kimchi intake rate of elementary school students, and also to determine the proper serving size per person on the menu items by grade.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.264-270
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• 2016

This Study is to into fuel using a torrefation reaction to food waste. When the fuel of only food waste alone, fuel value is was performed at a ratio of sewage sludge constant attempts to prevent low. Mixing ratios of food waste and sewage sludge, 10:0, 8:2, 6:4, 5:5. Regardless mixing ratio, it was possible to confirm that decreases the moisture content of 10% or less at a reaction temperature of $240^{\circ}C$ or higher. As the ratio of the reaction temperature and the sewage sludge is high, the fixed carbon content is increased. It was measured at up to 36%(mixing ratios6:4, reaction temperature $270^{\circ}C$) from the initial 1.1%. From the reaction temperature $240^{\circ}C$ satisfied with 3000Kcal/Kg or more is a SRF criteria shows the calorific value. It was possible to obtain a heating value that is increased from the raw sample approximately sextuple. As reaction temperature is heightened, Van krevelen Diagram moved to the range of Lignite range. It was possible to obtain high fuel ratio and 5,500Kcal/kg or less of a combustility index as the sewage sludge mixing ratio becomes high. Increase the fixed carbon content, than those food waste alone solid fuel into and improved fuel costs, it is necessary to ensure that the quality of the fuel is improved.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.105-118
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• 2005

This study examined the improvements of existing food waste statistics system using a sample survey, which estimated the total food waste generation in 4 areas(High, Middle, Middle and Low, and Low population density), and a survey, which was aimed at forming a basis for modeling 112 local governments, were conducted. Currently, the methods for collecting the statistical data are summarized as five types. In high population density areas, the type based on examining the recycling facilities was found to be a more general way of estimating population centers higher than low population density areas. It was found that numerous low population density areas estimated their food waste production according to its generation per capita. It was also found that the findings of sample survey were 10%~40% higher than the existing statistical data and Non-separated collected food waste appears to be the main factor.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.82-88
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• 2005

This study was carried out to investigate on the change of NaCl content during the food waste composting and on the safety of food waste compost(FWC) manufactured by the non-stirrer sealed fermenter. Plant culture test with pepper crop was also performed to see the effect of FWC, which was produced by the G co. ltd., on the growth of peper and migration of NaCl in soil. The culture test was performed at the farmland in Chungnam National University. The results were as follows; the NaCl content was gradually accumulated during food waste composting process, probably through water evaporation. Sodium concentration was, however, remarkably decreased at the final stage due to the desalting effect by water which was concentrated on the ceil of the fermentor. The analysis of chemical properties and humidity parameters on the food waste compost revealed that the product is quite a good qualified one. More than 0.5 tons of FWC application on red pepper cultivation caused diminished effect on the yield and the accumulation of salts on soil.

• Korean journal of food and cookery science
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• v.13 no.1
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• pp.30-39
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• 1997

The purpose of this study was to investigate food services and plate waste of the elementary school children in the urban, rural and suburban areas of Taegu and Kyoungpook province. Statistical data analysis was performed using the SPSS programs for Crosstabs analysis T-test, One-way Anova and Pearson's correlation. The results were as follows: The serving size of rice was greater in suburban area than in rural and urban area by the physical estimation. The amount of soup given was the greatest in rural area. The rate of waste in soup was higher than that of rice. Among side dishes, plate waste rate of braised potato was the highest in rural, then suburban and urban area. There were significant differences (p < .001) among the schools in the three areas. Especially, plate waste rate of cucumber and cabbage salad was the highest in all three areas. Then finally the serving size and plate waste rate of Kimchies were the greatest in rural, then suburban and urban schools. There were significant differences in 'spice pickled cabbage'(p < .001) and 'spice pickled radish'(p < .01) among the three areas. Plate waste amounts of egg soup and pine mushroom soup in urban area were greatest. In rural area, side dishes except egg soup, cabbage salad and Kimchies had a greater amount of plate waste. In suburban areas, there were smaller plate waste amount in rice, but plate waste amounts of pine mushroom soup and beef soup were great. Plate waste rate of rice and 'Kimchies' by children's rating estimation were significantly higher in rural than suburban and urban areas. There were no significant differences in plate waste rate of the given food except braised chicken (p < .001), soup (p < .001) and 'Kimchies' (p < .05) between the physical estimation and the children's rating estimation. Increased satisfaction on food service in most menus resulted decreased plate waste rate. There was a significant degree of satisfaction on the amounts of food served.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.3
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• pp.333-339
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• 2011

In the present work, it was attempted to produce $H_2$ from food waste by the two-stage fermentation system. Food waste was acidified to lactate by using indigenous lactic acid bacteria under mesophilic condition, and the lactate fermentation effluent (LFE) was subsequently converted to $H_2$ by photo-fermentation. $Rhodobacter$ $sphaeroides$ KD131 was used as the photo-fermenting bacteria. The optimal conditions for lactate fermentation were found to be pH of 5.5 and substrate concentration of 30 g Carbo. COD/L, under which yielded 1.6 mol lactate/mol glucose. By filtering the LFE and adding trace metal, $H_2$ production increased by more than three times compared to using raw LFE, and finally reached the $H_2$ yield of 3.6 mol $H_2$/mol lactate. Via the developed two-stage fermentation system $H_2$ yield of 5.8 mol $H_2$/mol glucose was achieved from food waste, whose value was the highest that ever recorded.

• Journal of the Korean Society of Industry Convergence
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• v.10 no.3
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• pp.137-141
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• 2007

The sugar content of persimmon fruits was decreased when food-waste compost was used. Dungsi was brighter with yellow color than that of control. The Gabjubaekmok was darker than that of control with red color. It was suggested that taste of astringent was reduced because total phenol and soluble tannin contents were reduced by that compost. The vitamin C content of persimmon fruits during storage was higher than that of control. Stability of persimmon fruits by that compost and usual compost was about the same at room temperature. At low temperature, hardness of persimmon fruits was maintained for 20days. Hardness and reducing sugar contents of persimmon fruits were increased by food-waste compost. The result was shown that there was no effect on composition of persimmon fruits by food-waste compost and maintaining hardness at room temperature, but at low temperature, the composition of persimmon fruits was changed.