• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.419-424
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• 1998

Removal of monochloropropanediol (MCPD) and improvement of quality of the soy-sauce made from acid-hydrolyzate of defatted soy protein (SAHSP) were examined by fermenting the soy-sauce with soy-sauce koji or koji plus Pediococcus soya or/and Saccharomyces rouxii. The overall fermentation process performed in this work consisted sequentially of autodigestion of soy-sauce koji $(at\;45^{\circ}C\;for\;12\;days)$, lactic acid fermentation $(at\;30^{\circ}C\;for\;14\;days\;in\;S3\;and\;S4)$, ethanol fermentation $(at\;30^{\circ}C\;for\;14\;days\;in\;S2\;and\;S4)$,and aging $(at\;25^{\circ}C\;for\;20\;days)$. At the end of the autodigestion period, the highest MCPD removal (from the initial 38.6 ppm to 1.3 ppm) was observed in the S-2. Reducing sugar contents of the S-2 and S-4 sharply decreased from the 30th day of incubation, from the initial concentration of about 5.0% to less than 0.5% at the end of the process. Total soluble nitrogen content of all the soy-sauce products slightly increased during the overall fermentating period.The level of free glutamic acid, a major amino acid that is known to determine the taste of soy-sauce was determined to be an average value of $1270{\sim}1323\;mg/100\;mL$ of soy-sauce. The results of sensory evaluation of the fermented SAHSPs show that qualities of the S-2 and S-4 samples are nearly on the same level with that of the commercially fermented soy-sauce (p<0.05). This result suggests that the fermentation process in this work, especially the process performed with S. rouxii has a good effect for removing MCPD from SAHSP and also for improving quality of the SAHSP product.

• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.265-271
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• 2004

A feeding trial was conducted to investigate the influence of feeding Lactobacillus reuteri culture (LR) on productive performance, intestinal microflora and availability in laying hens. Four hundred and eighty, Isa-Brown layers, 49 weeks of age, were fed diets supplemented with LR at the level of 0 (control), 0.1, 0.2, and $0.4\%$ of the diets for eight weeks. Egg production and egg weight were measured daily. Feed intake was weighed every two weeks. Egg quality was measured three times at the start, mid-term, and end of the experiment. Intestinal microflora were examined for Lactobacillus spp., E. coli and Salmonella at the end of the experiment. Overall egg production was the highest in $0.2\%$ LR (P<0.05), but that of $0.1\%$ or $0.4\%$ LR treatments did not significantly differ from that of control. Egg weight was significantly higher in LR feeding group than the control (P<0.05). Daily egg mass was significantly higher in $0.2\%$ and $0.4\%$ LR treatments compared to the control and $0.1\%$ LR (P<0.05). The number of jumbo and extra large eggs were increased in LR supplemented groups, especially in $0.1\%$ LR. Feed intake of layers fed LR supplemented diets tended to be lower than the control. However, feed conversion ratio significantly improved in LR supplemented groups (P<0.05). Availability of dry matter and crude protein improved significantly in $0.4\%$ LR treatment (P<0.05). But, those of ether extract and crude ash were not significantly different among treatments. Eggshell breaking strength and eggshell thickness were not significantly influenced by LR supplementation, and Haugh unit and yolk index were also similar to the control. Total number of Lactobacillus spp. in ileum and cecum fed LR supplemented diets were significantly higher than those of the control (P<0.05). There were no significant differences in intestinal E. coli and Salmonella in all treatments. Therefore, it is concluded that dietary supplementation of Lactobacillus reuteri culture can improve the laying performance, feed efficiency and intestinal Lactobacillus.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.77-82
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• 1999

Three floating islands have been constructed for water quality improvement for a polluted irrigation reservoir. Each floating island consists of 10 segments. Each segment hay an area of $16m^2$(4×4m) and is made of wood frames and floats(polystyrene foam). We planted three species of aquatic macrophytes(Typha angustifolia, Zizania latifolia, and Phragmites australis) in floating island on June, 1998. They grew very well without death. We would like to evaluate Phragmites australis is the most suitable aquatic macrophyte that could be planted in a floating island because it maintained the best balance of its root and shoot among them. During their grown period, net primary productivity of Typha angustifolia was $962gDM/m^2$, Zizania latifolia was $1,115gDM/m^2$, and Phragmites australis was $523gDM/m^2$. From these data, it would be estimated to 5.0Kg uptake of nitrogen by aquatic macrophytes and phosphorus 0.8Kg in 3 floating islands. The floating islands worked well as a habitat of fish and prawns. Many kinds of insect lived on the floating islands. The floating island has not only the function of water quality treatment but also several advantages: improvement of landscape and species diversity; low cost of maintenance; low technology; unnecessary of energy; less susceptible to variations in pollutant loading. It could be evaluated a good measure of water quality improvement for an irrigation reservoir. However, it should be intensively studied to develop more light, strong, durable and low-priced frames for efficient floating islands.

• The Korean Journal of Pesticide Science
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• v.6 no.1
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• pp.16-24
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• 2002

Research trends in the measurement of foliar uptake of pesticides and the recently proposed action mechanism of the surfactant-induced uptake of pesticides were reviewed with the related reports and studies. Major techniques used in those fields are bioassay, radiotracer techniques with leaves or cuticular membrane. Recently, a new method using Congo Red as a tracer was proposed. The limiting factor in the pesticides uptake into leaves is the waxy layer which consists of the epicuticular and cuticular wax. Physico-chemical parameters such as molar volume, water solubility and partition coefficient of pesticides have limited influences on the pesticide uptake into leaves. Polydisperse ethoxylated fatty alcohol surfactants are well known as the good activator for many pesticides. It is now generally agreed that uptake activation is not related to the intrinsic surface active properties of surfactants such as surface activity, solvent property, humectancy and critical micelle concentration. Recent studies using ESR-spectroscopy revealed that the surfactants have an unspecific plasticising effect on the molecular structure of the wax and cuticular matrix, leading to increased mobilities of pesticides. Penetration of surfactants into waxy layer altered the pesticide mobility in wax and the partition coefficient of pesticide, and then the pesticides penetration into leaves was enhanced temporally. The enhancing effect of surfactant could be significantly different depending on the carbon number of aliphatic moiety and the number of ethoxy group in polyoxyethylene chain of surfactants. It is suggested that the rate of penetration of surfactants should have a significant relationship with the rate of penetration of pesticides.

• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.126-132
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• 2013

The objectives of this study were to provide the basic data of the residue of deltamethrin in the stream water. Deltamethrin was treated on side of Ban-Suk stream and Juk-Dong ditch for hygienic purpose by air spray. The drift concentration of deltamethrin was investigated with different wind speed condition on Ban-Suk stream (A), and the change of residue with time course on Juck-dong ford (B). Also we found the residual change of deltamethrin until 48 hour in Yu-Seong stream confluence (C) where two streams join. Maximum residues of A were $0.17{\mu}g/L$ (5 min, 200 m) at strong wind speed and $4.42{\mu}g/L$ (0 min, 25 m) at moderate wind speed according to different wind velocity. Residues of B were $0.15{\sim}0.26{\mu}g/L$ (0~480 min) after spraying, and decreased to a non-detected level after 720 min. Residues of C were $0.15{\mu}g/L$ (0 min), $0.11{\mu}g/L$ (1 min) and $0.10{\mu}g/L$ (12 hr) after spraying, and no residues were detected in any other samples. From these results, it is concluded that deltamethrin residues in water should be rapidly diluted into stream water and affected negligible toxic effect to stream ecosystem.

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.148-158
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• 2009

We tested and selected some agrochemicals reducing the occurrence of major pests and diseases during garlic storage. Tebuconazole, diphenylamine and prochloraz as fungicides and dimethate as a insecticide were sprayed or drenched before harvest. And the harvested garlic was dipped in each of the agrochemicals. The residues of pesticides in garlic bulbs treated were analyzed every month from harvesting time for 6 months. In case of Danyang garlic, which was treated with pesticides before and after harvesting, the residues of diphenylamine, tebuconazole, prochloraz, and dimethoate ranged from 0.008 to 0.28, from 0.03 to 0.32, from 0.02 to 0.12, and from 0.02 to 0.25 mg/kg, respectively. In case of Uiseong garlic, the residues of diphenylamine, tebuconazole, prochloraz and dimethoate ranged from 0.008 to 0.09, from 0.08 to 0.45, from 0.02 to 0.57, and from 0.04 to 0.38 mg/kg, respectively. And, in case of Namdo garlic, the residues of diphenylamine, tebuconazole, prochloraz, and dimethoate ranged from 0.008 to 0.52, from 0.07 to 1.67, from 0.02 to 0.17, and from 0.03 to 0.73 mg/kg, respectively. Some of the garlic samples treated with tebuconazole exceeded its maximum residue limits (MRLs) of 0.1 mg/kg set by Korea Food Drug Administration (KFDA), but dimethoate was detected below its MRL of 1.0 mg/kg. In case of diphenylamine and prochloraz, their MRLs for garlic were not set. Adapting their MRLs, 5.0 mg/kg of diphenylamine for apple and pear and 0.5 mg/kg of prochloraz for strawberry and grape, residue levels of diphenylamine and procloraz were below than their MRLs, with the exception of samples two times treated with procloraz in Namdo garlic. These results indicate that dimethoate can be used as an agrochemical to control the postharvest disease in garlic in only MRL aspect.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.285-292
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• 2011

In order to develop livestock wastewater treatment technology by natural purification method, the optimum filter media in small-scale livestock wastewater treatment apparatus for treating livestock wastewater were studied. Removal rates of pollutants under different filter media were in the other of coarse sand ${\fallingdotseq}$ broken stone > zeolite > calcite for COD, zeolite >> broken stone ${\fallingdotseq}$ coarse sand ${\fallingdotseq}$ calcite for T-N, and calcite > coarse sand ${\fallingdotseq}$ broken stone ${\fallingdotseq}$ zeolite for T-P. Based on the above results, the optimum filter media was coarse sand in small-scale livestock wastewater treatment apparatus. To meet acceptable effluent quality standard for livestock wastewater and to improve T-N and T-P removal efficiencies, removal efficiencies of pollutants in small-scale livestock wastewater treatment apparatus with mixed filter media were studied. The removal rates of COD, SS, T-N and T-P in effluent were 84, 94, 65 and 98% in small-scale livestock wastewater treatment apparatus with mixed filter media, respectively. For increasing the T-N and T-P removals in small-scale livestock wastewater treatment apparatus, the mixed filter media are recommended.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1993.12a
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• pp.6-9
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• 1993

According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. Thus. to prevent these undesirable changes , val'ious techniques such as controlled atmosphere (CA) storage, modified atmosphere OIA) storage, including vacuum packaging have been receiving considerable attention, Although milch research has been done to find optimal conditions for whole intact frui ts and vegetables, only limi ted information is avai lable on fresh cut. and other minimally processed products. 81 iced frui ts exhibi t increas~d ethylene production and respiration compal'ed to whole f, 'uits during distribution in response to tissue damage. As a result, accelerated senescence and enzymatic browning OCCUI', Recent l'esearch on minimally processed fl'uits and vegetables has mainly focused on methods to inhibit browning, due to ban on use of sulfur dioxide, In order to retard or prevent these physiological changes, val'ious al ternatives, reducing agents. acidulants, chelating agents and inol'ganic sal ts have been evaluated for use on fresh cut fl'ui ts. Al though some agents were effective replacement for sulfur dioxide. consum$\textregistered$I'S demandless use of chemical on such products. Shel~ life of minimally processed products has been extended by inhibition of metabolic reactions associated with loss of quality and by inhibition of aerobic spoilage caused by wide variety of microorganisms. Appl ication of ~I.-\ packaging, including vacuum packaging, retards the rate of respiration, prevents growth of aerobic spoilage organisms, inhibits oxidation and color deterioration. Tissue softening is another major problem in minimally processed products because enzymes re 1 a ted to ce 11 wa 11 degrada t i on are not inactivated. Various treatments have been investigated for retardation of the softening of sliced products. Some studies have concentrated on the application of an active packaging system with ~I, l. packaging and calcium infi 1 tration as possible measures to retain firmness of processed products. In my opinion, one important step for production of minimally processed frui ts wi th favorabl e color of cut surface and firm texture is the selection of better cultivar. As the view, changing tendency of fresh color by apple cultivars and relationship between the tendency and PPO activity will be discussed in the seminar. In addition to the topic, research result on quality enhancement of fresh apple slices by heat shock treatment will be introduced.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.68-75
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• 2016

This study was conducted to provide information regarding changes in antioxidant activity in response to conching temperatures, conching times, and cacao mass content (CMC) in dark chocolate. The radical scavenging activities and functional components of cacao nibs were highest for raw cacao nib (R0) under all conditions. Moreover, antioxidant activities and functional compounds increased during roasting for 25 min. As the conching temperature increased, the radical scavenging activities and functional components increased. Quantitative analysis of major catechin-derived compounds by HPLC revealed that R0 had the highest value for other roasted cacao nibs in all aspects (P<0.05). The content of procyanidin B2, catechin, and epicatechin increased during roasting for 25 min. Finally, evaluation of couvertures revealed that procyanidin B1 content increased as conching time increased to 48 h, except for 70% CMC and conched at $60^{\circ}C$ (HH) and 70% CMC and conched at $50^{\circ}C$. Overall, HH48 contained the richest catechin-derived components.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1258-1264
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• 2009

The removal effects of two commonly used pesticides of Bifenthrin and Metalaxyl during preparation and fermentation of kimchi were studied. The two pesticides were applied to Baechu cabbages intentionally for 20 seconds; the applied amounts of Bifenthrin and Metalaxyl were 3.02$\pm$0.09 ppm and 6.79$\pm$0.17 ppm, respectively. The Baechu cabbages were washed by water 3 times. Then the residual amounts of the two pesticides of Bifenthrin and Metalaxyl were measured and the removal rates were 21.7% and 16.1%, respectively. When Baechu cabbages were brined with 10% salt solution for 12 hours after the application of the two pesticides, the removal rates significantly increased to 98.7% and 60.8%, and when brined and washed 3 times by water, the removal rates even more increased to 99.7% and 73.4% respectively. Then we made kimchi and investigated the quantities of the residual pesticides during the fermentation at $4^{\circ}C$ for 3 weeks. The residual amounts of the pesticides in kimchi decreased in a time dependent manner, finally the amounts of the pesticides to 0.35$\pm$0.04 ppm and 0.48$\pm$0.06 ppm while the removal rates of the two pesticides were 57.8% and 81.0%, respectively. When the kimchi was fermented at $4^{\circ}C$ and $10^{\circ}C$ for 3 weeks, the removal rates of Bifenthrin were 57.8% and 72.2% and those of Metalaxyl were 81.0% and 85.6%, respectively. Consequently, it appeared that the residual pesticides can be removed during preparation, especially brining; the fermentation process of kimchi also removed the residual pesticides effectively, especially at higher temperature and long period.