• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.584-589
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• 2005

Structured triacylglycerol (SL-TAG) was synthesized by enzymatic interesterification with algae oil and soybean oil in solvent-free system. Structured di- and monoacylglycerol (SL-DAG/MAG) were produced by glycerolysis with SL-TAG and glycerol catalyzed by lipase. Reactions were performed by sn-1.3 specific Lipozyme RM IM lipase from Rhizomucor miehei (interesterification, 11%; glycerolysis 5% by weight of total substrates) in solvent-free system using stirred-batch type reactor. SL-DAG/MAG contained TAG (42,3 area%), 1,3-DAG (19.2 area%), 1,2-DAG (22.2 area%), MAG (16.0 area%), and free fatty acid (0.2 area%). Iodine and saponification values of SL-DAG/MAG were 208.8 and 179.6, respectively. SL-DAG/MAG appeared yellowish in color.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.202-208
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• 2006

Juice obtained from premature citrus fruits was deacidified by electrodialysis (ED), and its physicochemical and functional properties were evaluated. Total acidities decreased from 3.15 (Aug), 1.62 (Sep), and 1.45% (Oct) to 2.37 (Aug), 0.86 (Sep), and 0.74% (Oct) by electrodialysis for 100 min, respectively, whereas $^{\circ}Brix$ to acid ratio increased, and pH and color remained almost unchanged. Free sugar content of premature citrus juice remained almost unchanged, while organic acid content decreased significantly. Narirutin and hesperidin contents among flavonoids slightly, but not significantly, decreased. $K^+,\;PO_4\;^{2-},\;SO_42^-,\;and\;Cl^-$ contents decreased by ED, with $K^+$ content showing more than 60% decrease, while $Na^+$ content increased 2.5-3.5 times. Total polyphenol content and electron-donating ability decreased slightly by ED, while nitrite-scavenging ability remained almost constant. Sensory evaluation indicated juice (Sep) subjected to ED processing to $12^{\circ}Brix$ with sugar had the highest preference.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.587-593
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• 2009

This study was carried out to investigate the quality characteristics of ginseng Jung Kwa and Jung Kwa solution prepared according to boiling frequency on Jung Kwa process. Ginseng Jung Kwa was made as follows: washed ginseng 8 kg was boiled 5 min with water 16 kg and then boiling water 8 kg was removed. Sucrose 10 kg was added to boiled ginseng soaking in hot water. Jung Kwa was boiled down for 60 min in sugar syrup and soaked for 24 hrs. According to the above process, Jung Kwa was boiled down 5 times. Moisture and pH of Jung Kwa and Jung Kwa solution decreased as the number of boiling time increased and $^{\circ}Brix$ of Jung Kwa solution increased. Crude saponin content of last Jung Kwa (GJ 6) increased to 4 times of raw ginseng. Content of Rf and Rd, component of ginsenosides, increased 77 and 16 times on Jung Kwa, respectively and content of crude saponin on last Jung Kwa solution (GJS 5) was 61.88 mg/g. The other ginsenosides on Jung Kwa decreased. As the number of boiling time increased, concentration of total sugar, glucose and fructose of Jung Kwa and Jung Kwa solution increased. Content of total organic acid on Jung Kwa decreased, especially, succinic acid, main organic acid of ginseng, decreased rapidly. L value of Jung Kwa decreased whereas a and b values increased.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.297-307
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• 2018

The aim of this study was to develop a seasoning paste fermented by Aspergillus oryzae and Bacillus subtilis using three edible insects: Tenebrio molitor larvae, Gryllus bimaculatus, and Bombyx mori pupa. No significant changes in pH and titratable acidity were observed between the insect pastes and soybean control during a 5-week fermentation process. The amino nitrogen was 0.35-0.50% (w/w) in the early stage of the fermentation and increased to 0.72-0.78%. The total nitrogen was 2.36-3.62% (w/w) in the early stage and was preserved during the fermentation period. Free amino acids of the insect pastes were similar to those in soybean paste. In general, the fermented insect pastes showed a lower flavor and color than soybean paste but B. mori pupa-fermented paste did not show any significant difference in preference from soybean. Glutamate, aspartate, lysine, phenylalanine, arginine, and serine were found to affect taste preference. It was possible to ferment edible insect protein to produce a fermented seasoning paste like Korean doenjang.

• Food Science and Preservation
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• v.15 no.5
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• pp.642-647
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• 2008

This study investigated the microbiological and sensory characteristics of Kongnamul muchim stored with gamma-irradiated red pepper powder at $4^{\circ}C$. Total aerobic microbes in raw Kongnamul muchim were 5.72 log CFU/g in the red pepper powder and 2.40 log CFU/g in the garlic used during storage, but were not detected n other raw materials. Coliform bacteria and fungi were found, at 3.11 and 3.48 log CFU/g respectively, only n the red pepper powder. Microorganisms in Kongnamul muchim stored with gamma-irradiated (10 kGy) red pepper owder were not detected over 3 days of storage at $4^{\circ}C$. The pH, Hunter's color value, and sensory characteristics id not change significantly on storage. These results suggest that the addition of gamma-irradiated (less than 10 Gy) red pepper powder could improve the microbiological safety of Kongnamul muchim without changing desirable ensory characteristics.

• Journal of the Korean Society of Groundwater Environment
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• v.7 no.3
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• pp.103-115
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• 2000

The formation of brown-colored precipitates is one of the serious problems frequently encountered in the development and supply of groundwater in Korea, because by it the water exceeds the drinking water standard in terms of color. taste. turbidity and dissolved iron concentration and of often results in scaling problem within the water supplying system. In groundwaters from the Pajoo area, brown precipitates are typically formed in a few hours after pumping-out. In this paper we examine the process of the brown precipitates' formation using the equilibrium thermodynamic and kinetic approaches, in order to understand the origin and geochemical pathway of the generation of turbidity in groundwater. The results of this study are used to suggest not only the proper pumping technique to minimize the formation of precipitates but also the optimal design of water treatment methods to improve the water quality. The bed-rock groundwater in the Pajoo area belongs to the Ca-$HCO_3$type that was evolved through water/rock (gneiss) interaction. Based on SEM-EDS and XRD analyses, the precipitates are identified as an amorphous, Fe-bearing oxides or hydroxides. By the use of multi-step filtration with pore sizes of 6, 4, 1, 0.45 and 0.2 $\mu\textrm{m}$, the precipitates mostly fall in the colloidal size (1 to 0.45 $\mu\textrm{m}$) but are concentrated (about 81%) in the range of 1 to 6 $\mu\textrm{m}$in teams of mass (weight) distribution. Large amounts of dissolved iron were possibly originated from dissolution of clinochlore in cataclasite which contains high amounts of Fe (up to 3 wt.%). The calculation of saturation index (using a computer code PHREEQC), as well as the examination of pH-Eh stability relations, also indicate that the final precipitates are Fe-oxy-hydroxide that is formed by the change of water chemistry (mainly, oxidation) due to the exposure to oxygen during the pumping-out of Fe(II)-bearing, reduced groundwater. After pumping-out, the groundwater shows the progressive decreases of pH, DO and alkalinity with elapsed time. However, turbidity increases and then decreases with time. The decrease of dissolved Fe concentration as a function of elapsed time after pumping-out is expressed as a regression equation Fe(II)=10.l exp(-0.0009t). The oxidation reaction due to the influx of free oxygen during the pumping and storage of groundwater results in the formation of brown precipitates, which is dependent on time, $Po_2$and pH. In order to obtain drinkable water quality, therefore, the precipitates should be removed by filtering after the stepwise storage and aeration in tanks with sufficient volume for sufficient time. Particle size distribution data also suggest that step-wise filtration would be cost-effective. To minimize the scaling within wells, the continued (if possible) pumping within the optimum pumping rate is recommended because this technique will be most effective for minimizing the mixing between deep Fe(II)-rich water and shallow $O_2$-rich water. The simultaneous pumping of shallow $O_2$-rich water in different wells is also recommended.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.10-17
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• 2014

This study was conducted to elucidate the relationship between light and coloring and to obtain basic results for promoting redness expression in 'Kalle' (Pyrus communis L.) pear skin. It was investigated in location of anthocyanin layer by microscopic observation and differences in skin color expression of 'Kalle' bagged with paper bag which has different light transmittance rate and inside temperature. However, there was no anthocyanin layer in the brown skin and golden yellow color, anthocyanin layer was distributed in epidermins or hyperdermis of red skin pear and apple. Dark red colored 'Kalle' had more anthocyanin content, $29.8mg{\cdot}100g^{-1}$ FW than light red colored apple 'Hongro'. Light transmittance rate of physical characteristics used paper bags was the highest in white paper bag, 42.2% and it also had more light quantity, $8.9{\mu}mol$ than any other tested paper bags in specific wave length 650-655 nm. The maximum temperature of inner bag was higher about $3^{\circ}C$ in yellow paper bag. The red coloration and anthocyanin contents in no bagged fruits were higher than in any other bagged fruit. However, red color expression among the bagged fruits was higher in white paper bag than in double layered black paper bag and yellow paper bag. Also, chromaticity value seemd to be a good index to explain variation of fruit skin color, because anthocyanin content and chromaticity value were higher. Based on these results, it is desirable to cultivate 'Kalle' without bag for stable redness expression but bagging is essential for decreasing damage by insect in Korea. Further examination to find suitable time of removing paperbag for redness expression and decreasing insect damage. In addition, it is required to develop paperbag whose transmittance rate is high in specific light wavelength or temperature of inner bags is low. Additional key words: anthocyanin, bagging, chromaticity value, light transmittance, Pyrus communis L.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.4
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• pp.263-271
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• 2009

This study evaluated the flocs forming characteristics in the mixing zone to increase the coagulation effect in the drinking water plant. As a measuring tool of formed flocs, on-line particle dispersion analyzer (iPDA) was used in Y drinking water plant. To evaluate the forming flocs, many parameters such as poly amine, coagulant dosing amount, raw water turbidity, and pH was applied in this study. During the periods of field test, poly aluminium chloride (PACl) as a coagulant was used. With the increase of the raw water turbidities, poly amine was also added as one of aids for increasing in coagulation efficiency. The turbidity and pH of raw water was ranged from 7 to 9 and from 25 to 140 NTU, respectively. The increasing of raw water turbidity brought the bigger floc sizes accordingly. From a regression analysis, $R^2$ value was 0.8040 as a function of T, raw water turbidity. Floc size index (FSI) was obtained from a correlation equation as follows; FSI = 0.9388logT - 0.3214 Also, polyamine gave the bigger flocs the moment it is added to the coagulated water in the rapid mixing zone. One of parameters influencing the floc sizes was the addition of powdered active carbon(PAC) in the mixing zone. In case of higher turbidity of raw water, $R^2$ value was 0.9050 in the parameters of [PACl] and [PAC]; FSI = $0.0407[T]^{0.324}[PACI]^{0.769}[PAC]^{0.178}$ On-line floc monitor was beneficial to evaluate the flocs sizes depending on the many parameters consisting raw water properties, bring the profitable basic data to control the mixing zone more effectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.389-396
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• 2014

The physiological properties of 70% ethanol extracts from Portulaca oleracea with different extraction methods (reflux extraction, RE; autoclave extraction, AE; low temperature high pressure extraction, LTPE) were investigated. The freeze-dried powder yields of RE, AE, and LTPE were 33.78%, 30.80%, and 11.05%, respectively. The color values of L and b were higher in LTPE, and the chroma values were higher in AE and LTPE compared to RE. The total polyphenolics and proanthocyanidin contents in LTPE were significantly higher than in other extracts. The amount of substances related to flavonoids contents was highest in RE (4.30 mg/g), followed by AE (4.06 mg/g), and LTPE (4.00 mg/g). DPPH radical scavenging ability with a concentration of 500 mg% (w/v) were in the following order; LTPE (88.87%)> RE (83.84%)> AE (80.67%). Further, the reducing power, ABTS radical scavenging ability, and nitrite scavenging activity was observed in the same tendency as seen with the DPPH radical scavenging ability. However, the ferrous ion chelating activity of RE (85.45%) and AE (83.88%) was significantly higher than that of LTPE (75.60%). ${\alpha}$-Glucosidase inhibitory activities of RE and LTPE with a concentration of 100 mg% were significantly higher than AE. Xanthine oxidase, and acetylcholinesterase inhibitory activities of LTPE were higher than the other extracts. These results suggest that the extracts from Portulaca oleracea have the potential to act as functional materials, and components of Portulaca oleracea could be effective in the prevention of Alzheimer's disease, and may be used to develop various functional food products.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.288-293
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• 1986

The washed fresh ginsengs packed with air, vaccum and nitrogen gas were irradiated at the levels of 1,2 and 3kGy gamma radiation and then stored at $4{\sim}5^{\circ}C$ for 90days to investigate the effects of gamma radiation on microbial inactivation, eelworm disinfestation and physicochemical changes. After a 90 day storage, $2{\sim}3kGy$ irradiated groups showed 20% of weight loss and 10% of rot while non-irradiated group 100% and 20% or more, respectively. Also the irradiated groups showed somewhat lower values of specific gravity, color density and hardness immediately after irradiation, thereafter higher value of them with storage time than those of non-irradiated group. The irradiation increased the yields of ginseng extract and crude saponins but no effects on the proximate composition and TLC and HPLC patterns of saponin. The food-borne microorganisms decreased in viable cell counts by $2{\sim}3$ log cycles with $2{\sim}3kGy$ radiation and the eelworms were completely disinfested with 1 kGy radiation.