• The Korean Journal of Ecology
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• v.16 no.2
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• pp.169-180
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• 1993

Soils of four combinations, sand with high content of organic matter(SL), sand with low content of OM(SS), siltyl loam with high content of OM(LL) and silty loam with low content OM (LS), were filled on column and then percolated with simulated sulfuric acid rain with pH 5.6, 4.0, 3.5, 3.0 and 2.5. From soil leachates, pH and concentrations of basic cations and Al were determined. Cation concentrations in the leachates increased as pH of the rain decreased. The orders of buffering capacity of soil, leachability of cation from soil, leaching sensitivity of ion andbase saturation sensitivity of soil to acidity of the rain water were SS$\leq$K <$\leq$LL

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.11a
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• pp.77-79
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• 2003

The effects of dietary supplementation of feather meal digests(FM) and its digests on the growth of broiler chicks and taurine content in the broiler meat were examined. Total of 100 broiler chickens were assigned to five dietary treatments: T1； Control, T2； feather meal(FM) 5 ％ diet, T3； NaOH treated FM 5％ diet, T4； HNO$_3$treated FM 5 ％ diet and T5； synthetic taurine 0.5 % supplemented diet. Taurine content of leg muscle was significantly(P＜0.01) increased by treatments. The highest increase over the control was shown by 0.5 ％ taurine diet(170 ％), followed by FM diet(123 ％), NaOH treated FM diet(122 ％) and HNO$_3$treated FM diet(63 ％). Taurine content of breast muscle was increased by 246 ％ in 0.5 ％ taurine diet but FM diets were not significantly different from the control. Taurine content of heart muscle was not significantly affected by dietary treatments. There were big differences in the average taurine content of the parts or organ of the control birds; 778 $\mu\textrm{g}$/g leg muscle, 79 $\mu\textrm{g}$/g breast muscle and 1482 $\mu\textrm{g}$/g heart muscle. It was concluded that taurine content of leg muscle of broiler can be increased by supplementation of feather meal. Alkaline or acid treatment FM was not effective in improving taurine enrichment of the broiler meat.

• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.319-327
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• 2000

This study was conducted to prolong the edible period of Kimchi by adding chitosan (0.25, 0.5%) and sodium salts of various organic acids(0.01~0.04M citrate, malate, lactate) . The edible period was estimated by measuring changes in pH. titratable acidity(TA), PH/TA ratio, ascorbic acid content and pectin fraction during Kimchi fermentation at 2$0^{\circ}C$. The results were compared by estimating the maturity of Kimchi fermentation. Kimchi with the chitosan showed higher pH and titratable acidity throughout the fermentation period than that without chitosan. The pH decreased during the fermentation in the order of control, 0.25% chitosan, 0.5% chitosan, 0.5% chitosan+Na-citrate, 0.5% chitosan+Na-malate and 0.5% chitosan+Na-lactate. But the titratable acidity increased in the order of control, 0.5% chitosan+Na-malate, 0.25% chitosan. 0.5% chitosan+Na-citrate, 0.5% chitosan and 0.5% chitosan+Na-lactate. The PH/TA ratio decreased in the order of control, 0.25% chitosan, 0.5% chitosan+Na-malate, 0.5% chitosan, 0.5% chitosan+Na-citrate and 0.5% chitosan+Na-lactate. Ascorbic acid content in Kimchi was the highest at the 3rd day and then decreased during fermentation. Ascorbic acid content in Kimchi containing 0.5% chitosan and organic acid salts was higher than others. Alcohol insoluble solids( AIS ) in Kimchi decreased during fermentation in the order of control, 0.25% chitosan, 0.5% chitosan, 0.5% chitosan+Na-palate. 7.5% chitosan+Na-lactate and 0.5% chitosan+Na-citrate. During fermentation, hot water soluble pectin (HWSP) of control increased, whereas HCI soluble pectin (HCISP) decreased. By addition of chitosan, however, the results became reverse. Chitosan addition appeared to be effective in improving preservation quality of Kimchi during fermention. The edible period become extended by using chitosan plus organic acids instead of using chitosan only. Overall. addition of 0.5% chitosan+Na-lactate seemed most effective in prolonging the edible periods during Kimchi fermentation.

• Culinary science and hospitality research
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• v.18 no.1
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• pp.40-53
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• 2012

The quality changes of vegetables including cucumbers, young pumpkins, carrots, radishes, onions by different cooking methods in $90^{\circ}C$ water, 0.5% NaCl solution, 1.0% NaCl solution and $400^{\circ}C$ superheated steam were investigated. The changes in pH of cooked vegetables were increased. Hunter color system values for L(lightness), a(redness) and b(yellowness) of the vegetables cooked in $400^{\circ}C$ supetbeated steam for 30 seconds were less compared with those in $90^{\circ}C$ water, 0.5% NaCl solution and 1.0% NaCl solution. The microbial growth was inhibited very effectively when the vegetables cooked in $400^{\circ}C$ superheated steam for 30 seconds. After cooked in $90^{\circ}C$ water, 0.5% NaCl solution, 1.0% NaCl solution, $400^{\circ}C$ superheated steam, vitamin C content decreased by different ratio depending on cooking methods and vegetable varieties. Based on the results of the quality changes of cooked vegetables, the superheated steam cooking method showed a positive effect on sterilization and maintaining pH, color, hardness of vegetable tissues, vitamin C content. The data obtained from this study could be utilized as basic information for the optimum conditions of superheated steam cooking to develope HMR(Home Meal Replacement).

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.87-94
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• 2013

To investigate the effects of functional MA films (FMA) masterbatched by zeolite powder treated with 1 N HCl, 0.5 N NaCl solution and anti-fogging agent (NA) compared with control on the freshness extension of 'Fuji' apples during storage at $15^{\circ}C$. Preference, weight loss, total ascorbic acid, sugar content, acidity, change of gas composition in package were measured. After 150 days of storage, the weight loss of control (L) apples was 1%, that of apple in FMA film (NA) was 1.5% after 150 days. Total ascorbic acid content of apples in control (L) after 150 days was 2.09 mg%, those of apple in FMA film (NA) was 2.72 mg%. The titratable acidity of apple in FMA film was higher than that in control, while soluble solids content of apples in FMA film was lower than that in control after 150 days. Ethylene gas adsorbability in control was 192.2 ppm and those in FMA film was 141.4 ppm after 150 days. Overall, apples in FMA film was better than that of control. It was verified that apples packed with LLDPE film (control) lasted about 130days, while those with FMA films lasted about 170 days. Also, FMA films treated with anti-fogging agent few different compare to nontreated film, but commerdity on the display in market was considered higher than that of non-treated anti-fogging agent.

• Applied Biological Chemistry
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• v.35 no.6
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• pp.437-442
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• 1992

In order to develop color of potato chip made from Superior variety and Irish Cobbler variety, various conditions on NaCl and $CaCl_2$ contents, heat treatment and soaking time were applied. The content of reducing sugar decreased by $30{\sim}40%$ in blanching without NaCl and $CaCl_2$. In NaCl soaking case, reducing sugar content decreased by $15{\sim}30%$, however, partial colorization was appeared that the sample turned to brown. In the sample that were soaking in NaCl solution and heat treated, reduction of reducing sugar was 40% and desirable time for heat treatment was 5 min and 7 min. In the sample treated $CaCl_2$ solution, reduction of reducing sugar was $25{\sim}30%$ and then color was not acceptable. In the sample soaking $CaCl_2$ solution and heat treated, reducing sugar content rapidly by 50% and the color development was the most ideal.

• Journal of the Korean Society of Food Culture
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• v.17 no.2
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• pp.197-213
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• 2002

In order to establish the processing condition of rapid- and low salt-fermented liquefaction of anchovy (Engrulis japonica), effect of temperature on crude enzyme activity of anchovy viscera, pretreatment conditions, and the minimum content of adding NaCl were investigated. The minimum limitation of NaCl content for anchovy liquefaction was 10%. Sample A(water adding, heating, adding 10% NaCl): chopped whole anchovy adding 20% water and then heating for 9 hrs at $50^{\circ}C$ and then adding 10% NaCl and then fermented at room temperature$(8-29^{\circ}C)$ for 180 days. Sample B(water adding, heating, adding 13% NaCl): chopped whole anchovy adding 20% water and then heating for 9 hrs at $50^{\circ}C$ and then adding 13% NaCl and then fermented at room temperature for 180 days. Sample C(adding 13% NaCl): chopped whole anchovy and then adding 13% NaCl and then fermented at room temperature for 180 days. Sample D(adding 17% NaCl): whole anchovy adding 17% NaCl and then fermented at room temperature for 180 days. The content of free amino acids such as aspartic acid, serine and threonine fluctuated severely according to the pretreatment methods. Possibly they might be recommend quality indices of standardization for salt-fermented liquefaction of anchovy. As for the relation between fermentation period(X) and individual free amino acid(Y), five kinds of free amino acids such as glutamic acid, valine, glycine, lysine, and alanine showed highly significant in their coefficient of determination in most of samples. They might be recommend as quality indices for salt-fermented liquefaction of anchovy during fermentation. The difference of taste between products of the rapid- and low salt-fermented liquefaction and the traditional salt-fermented liquefaction were caused by their composition of the free amino acids ratios, in which were umami, sweet, and bitter taste in the extracts of anchovy during fermentation. The appropriate fermentation period of the sample A was shorten 30 days than the sample B and 60 days than the samples C and 90 days than the sample D in the processing of anchovy.

• Journal of Korean Ophthalmic Optics Society
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• v.8 no.1
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• pp.1-5
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• 2003

Quarternary $Na_2O-B_2O_3-Al_2O_3-SiO_2$ glasses were fabricated by the function of $R({\equiv}Na_2O\;mole%/B_2O_3\;mole%)$ and $K({\equiv}(Al_2O_3\;mole%+SiO_2\;mole%)/B_2O_3mole%)$. The structures of these glasses were investigated through refractive index and vicker's hardness. The refractive index increased as the increase of the polarizability in the glass network. In the region of low $Na_2O$ content, the refractive index increased due to the increase of the polarizability in the glass network, but in the region of high $Na_2O$ content, the rate of increase of the refractive index decreased due to the increase of the molar volume caused by the formation of $BO_3{^-}$ units with relatively high molar volume. And, the refractive index decreased as the increase of $Al_2O_3+SiO_2$ content with the molar volume in the glass network. The increase and decrease of vicker's hardness values for those glasses depended on the fraction of tetrahedral $BO_4$ units and it of triangle $BO_3{^-}$ units with non-bridging oxygen, respectively.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.2
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• pp.300-308
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• 2004

The formation mechanism of anodic oxide films on Mg alloys when anodized in NaOH solution. was investigated by focusing on the effects of anodizing potential. Al content. and anodizing time. Pure Mg and Mg-Al alloys were anodized for 10 min at various potentials in NaOH solutions. $Mg(OH)_2$ was generated by an active dissolution reaction at the surface. and the product was affected by temperature. The intensity ratio of $Mg(OH)_2$ in the XRD analysis decreased with increasing applied potential. while that of MgO increased. The anti-corrosion properties of anodized specimens at each constant potential were better than those of non-anodized specimens. The specimen anodized at an applied potential of 3 V had the best anti-corrosion property. And the intensity ratio of $Mg_{17}Al_{12}$/Mg increased with aluminum content in Mg-Al alloys. During anodizing. the active dissolution reaction occurred preferentially in ${\beta}\;phase(Mg_{17}Al_{12})$ until about 4 mins. and then the current density increased radually until 7 mins. The dissolution reaction progressed in a phase(Mg) which not formed the intermetallic compound. which had a lower Al content. In the anodic polarization test of $0.017\;mol{\cdot}dm^-3$ NaCl and $0.1\;mol{\cdot}dm^-3\;Na_2SO_4$ at 298 K. the current density of Mg-15 mass% Al alloy anodized for 10 mins increased. since the anodic film that forms on the a phase is a non-compacted film. The anodic film on the phase for 30 mins was a compact film as compared with that for 10 mins.

• Macromolecular Research
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• v.17 no.11
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• pp.879-885
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• 2009

A macroazoinitiator (MAI) containing a poly(ethylene glycol) (PEG) segment was intercalated in the gallery of sodium montmorillonite (Na-MMT). Acrylic monomers were polymerized using this MAI intercalated in Na-MMT to prepare the acrylic copolymer nanocomposite (AN), which is a multiblock copolymer composed of two segments, an acrylic copolymer and PEG intercalated in Na-MMT (Na-MMT/PEG). When AN was used to modify the reactive hot melt polyurethane adhesive (RHA), the acrylic copolymer segment and Na-MMT/PEG synergistically enhanced the initial bond strength evolution and reduced the set time, even when the amount of Na-MMT in RHA was < 1 wt%. The viscosity of RHA increased and the tensile properties of the cured RHA film decreased due to modification with AN. These variations were more evident as the Na-MMT content in AN was increased.