• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1575-1581
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• 2011

Rapeseed cake, which is the organic waste remaining after rapeseed oil production, is readily available and considered an ecologically-friendly resource with very low cost and high dietary fiber content. This research was carried out for two reasons. First, it was done to analyze the liberated reducing sugar content of rapeseed cake. Second, it was done to investigate the effects on the sugar yield of the various concentrations of acidic and alkaline catalysts used for the hydrolysis of rapeseed cake and the concentrations of rapeseed cake in each catalyst. Several amounts of ground rapeseed cake, 0.5 g, 1 g, and 2 g, were put into 100 mL of catalysts such as sulfuric acid (0.5~2%), hydrochloric acid (0.5~2%), and sodium hydroxide (0.5~2%). Then they were hydrolyzed for 5 min at 121$^{\circ}C$. After hydrolysis, HPLC equipped with an RI detector was used to analyze liberated reducing sugars such as sucrose, glucose, galactose, fructose, and arabinose separated from rapeseed cake. The degradation rate of rapeseed cake was the highest in hydrochloric acid. As the catalyst concentrations used for hydrolysis of rapeseed cake increased, the degradation rate of rapeseed cake also significantly increased. Total reducing sugar content was the highest in hydrochloric acid, and it increased with the increase of catalyst concentrations. However, as the amount of rapeseed cake increased, the total reducing sugar content decreased, exceptionally sucrose in the case of sodium hydroxide.

• Economic and Environmental Geology
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• v.35 no.4
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• pp.325-337
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• 2002

We examined the contamination of stream water and stream sediments by heavy metal elements with respect to distance from the abandoned Backun Au-Ag-Cu mine. High contents of heavy metals (Pb, Zn, Cu, Cd, Mn, and Fe) and aluminum in the waters connected with mining and associated deposits (dumps, tailings) reduce water quality. In the mining area, Ca and SO$_4$ are predominant cation and anion. The mining water is Ca-SO$_4$ type and is enriched in heavy metals resulted from the weathering of sulfide minerals. This mine drainage water is weakly acid or neutral (pH; 6.5-7.1) because of neutralizing effect by other alkali and alkaline earth elements. The effluent from the mine adit is also weakly acid or neutral, and contains elevated concentrations of most elements due to reactions with ore and gangue minerals in the deposit. The concentration of ions in the Backun mining water is high in the mine adit drainage water and steeply decreased award to down stream. Buffering process can be reasonably considered as a partial natural control of pollution, since the ion concentration becomes lower and the pH value becomes neutralized. In order to evaluate mobility and bioavailability of metals, sequential extraction was used for stream sediments into five operationally defined groups: exchangeable, bound to carbonates, bound to FeMn oxide, bound to organic matter, and residual. The residual fraction was the most abundant pool for Cu(2l-92%), Zn(28-89%) and Pb(23-94%). Almost sediments are low concentrated with Cd(2.7-52.8 mg/kg) than any other elements. But Cd dominate with non stable fraction (68-97%). Upper stream sediments are contaminated with Pb, and down area sediments are enriched with Zn. It is indicate high mobility of Zn and Cd.

• Journal of the Korean Society of Food Science and Nutrition
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• v.10 no.1
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• pp.93-101
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• 1981

This study is designed to investigate the properties of caramel color made by corn sugar molasses, a new material. Com sugar refined and then caramelized in the solution of pH 2-10 ranges using catalysts such as ammonium carbonate, glycine and lysine. The control solution are 10% hydrochloric acid and sodium carbonate. The result were as follow; The caramelization showed the intensity of very strong color when added 0.4% ammonium carbonate as a catalyst. Color hue appeared to have the same color hue of the yellow belt and the red belt when compared with standard color hue in alkali, but the samples blue belt in all pH ranges showed a strong color hue than the standard color hue. Also, the stability of tannin, table salt and alcohol was transparent in all pH ranges, but the stability of acid appeared hazy at pH 9-10. In the case of glycine as a catalyst, caramelization showed the intensity of strong color when added 0.8% glycine at pH 9. Color hue showed in the yellow belt, strong in the red belt and very strong in the blue belt in all pH ranges when compared with standard color hue. Stability of tannin, table salt, acid alcohol was quite stable. In the case of lysine as a catalyst, caramelization showed strong color intensity when added 0.4% lysine in pH 9. Stability of tannin, table salt, acid and alcohol was quite stable.

• Applied Biological Chemistry
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• v.9
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• pp.71-81
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• 1968

Defatted rice bran is mixed with diluted acid solution, the mixture is agitated some hrs. at constant temparature. After the mixture is filtered, thus filtrate is obtained. This filtrate is phytin extract solution. (Test-1) The alkali is added to this filtrate and filtered out, then the precipitation of phytin is obtained. (Test-2) At the test-1, the effect of kind of acid, conc. of acid, amount of extract sol'n., time of extraction, temp. of extraction, to the extract amount of phytin is tested. Consequently, the following facts are known. 1. Amount of phytin extract is greater HCI extraction than $H_{2}SO_4$ extraction. 2. At 0.3% HCI, the amount of phytin extract is greatest of all HCl extraction. 3. The sufficient amount of acid solution is 8-10 times of amount of defatted rice bran. 4. The time of extraction at room temperature is sufficient 8-12 hrs. 5. When extract temperature is $20-30^{\circ}C$, the amount of phytin extraction is greater of all temp. 6, When defatted rice bran 20 g is shanken with 160 ml of 0.3% HCl for 10 hr. at room temp., in this case the amount of phytin extract is 11.34% of defatted rice bran, it is 93% of theoretical yield. At the test-2 the effect of kind of precipitation agent, degree of nutralization to the amount of phytin prcipitation is tested. 1. Degree of nut. is best at pH 6.8-7.0. 2. When use of $Ca(OH)_2$ the amount of phytin precipitation is more than use of KOH, NaOH, or $NH_{4}OH$. 3. At pH 6.0-7.2, the solubility of phytin is followed. K-phytate > $NH_{4}-phytate$ > Na-phytate > Ca-phytate 4. When phytin extract solution is nutralized with $Ca(OH)_2$ to pH 7.0, the amount of phytin precipitation is 94.78% of theoretical yield.

• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.548-561
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• 2001

Listeria spp. from sea water, fishes and shellfishes have been troubled in many countries. So we exam ined its distribution rates, biochemical characteristics of a separated strain, growth curve of pH at set times to 4 species of standard strain, and yes or no of growth inhibition for precautionary measure of food poisoning by L. monocytogenes, garlic, mustard, wasabi, and green tea extracts including sensitivity of antibiotics 10 species. As its results, check numbers of its positivity to Listeria spp. were 32 species in total examination body 200 species, and its isolation rates were 16%, L. innocua was 14.0%, L. monocytogenes 1.0%, and L. seeligeri 1.0% by the strain species. All the standard strain of 4 species showed growth inhibition bellow pH 3.0, its pH conditions of the optimum growth at 7.0∼8.0, and its growth was more active in alkali co]tuition than in acid condition. Its growth inhibition examination by garlic extracts had an the worst effects with O.D values of 0.078∼0.210. But the case of mustard and wasabi had weakened effect, and the case of green tea had some effect as the time went by. The results of sensitivity examination of antibiotics 10 species were as fellows. L. innocua of the 16 cases showed sensitivity of 100% in all 5 species, Ampicillin, etc, and Ciprofloxacin showed sensitivity of 43.7% and gentamicin, 93.7%. But tetracycline showed tolerance of 31.3% , cefotaxine. 75%, nalidixic acid, 100%. L. monocytogenes of the 6 cases showed sensitivity of 100% in all 6 species, ciprofloxacin, etc.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.5
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• pp.379-386
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• 1990

Varietal difference of protein content in forty eight Korean recommended rice cultivars and environmental Variation in protein content of milled rice harvested at six sites of the middle and/or southern plain and four locations of mid-mountainous and/or alpine area in 1989 were investigated. Also, the composition of amino acid in milled rice was compared among three rice varieties: a high-protein japonica rice, Nongbaek, a high-protein Tongil-type rice, Yongjubyeo, and a low-protein japonica rice, Hwaseongbyeo. Korean recommended rice varieties showed 7.93% of average protein content with varietal variation from 5.5% to 10.2% for milled rice harvested in 1988, and 9.17% of mean protein content with the variation from 6.3% to 12.0% for milled rice harvested in 1989. Tongil-type rice was about 1% higher in protein content of milled rice than japonica. The low-protein japonica rice, Hwaseongbyeo exhibited lower content of essential amino acids per g of rice flour sample than the high-protein japoinica, Nongbaek and/or Tongil-type rice, Yongjubyeo, but the relative content of essential amino acids per 16.8g of nitrogen in milled rice of the former was not so different with those of the latters. Among amino acids the content of glutamic acid was highest and among essential amino acids the content of leucine was highest while methionine was lowest. The protein content of milled rice was negatively correlated with days from seeding to heading, K/Mg ratio, alkali digestion value(l-7) and amylose content, but it was positively correlated with translucency and magnesium content of milled rice. The protein content of milled rice harvested in the southern plain paddy field was about 1% higher compared with those harvested in the Middle plain. Also, the protein content of milled rice harvested in the southern mid-mountainous and alpine area was about 0.8% higher compared with those harvested in the resemble altitude area of the middle-northern part of Korea. The contribution of environmental variation to total in plain area was about 28.1% while that in mid-mountainous and alpine area was about 56.4%.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.22-27
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• 1993

Crude ${\beta}-glucan$ extracted from Barley was purified by stepwide enzyme treatment with thermostable ${\alpha}-amylase$, amyloglucosidase and protease. The thermal properties of Barley ${\beta}-glucan$ were investigated by Differential Scanning Calorimetry. Three endotherms have been observed on DSC thermograms of Barley ${\beta}-glucan$. The first endotherm which produced the gelatinization phenomena commonly observed in Barley ${\beta}-glucan$ became the focus of this study. The temperature range and the enthalpy of gelation exhibited maximum values with increasing concentration of Barley ${\beta}-glucan$. Gelating Barley ${\beta}-glucan$ registered an enthalpy of approximately 0.23 cal/g and exhibited onset temperature (To), peak temperature (Tp) and conclusion temperature (Tc) of $48.8^{\circ}C,\;61.2^{\circ}C\;and\;78.5^{\circ}C$ respectively. The temperature and enthalpy of gelatinizing Barley ${\beta}-glucan$ at both alkali and acid conditions were lower than those at pH 7. With salt present, the Tp and Tc of gelating Barley ${\beta}-glucan$ produced lower temperatures than in conditions where salt was absent, and the enthalpy abruptly decreased. However, increasing salt concentrations did not affect the gelation temperature and the enthalpy of Barley ${\beta}-glucan$. The 'true melting' temperature of Barley ${\beta}-glucan$ was near $184^{\circ}C$ and the melting enthalpy was approximately 34.6 cal/g. The Barley ${\beta}-glucan$ decomposition temperature was in the range of $316^{\circ}C{\sim}346^{\circ}C$.

• Applied Biological Chemistry
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• v.47 no.1
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• pp.55-60
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• 2004

Changes of cell wall components and softening enzyme during the preparation of persimmon pickles with soy sauce and soy paste were investigated. The contents of alcohol insoluble substance and cell wall extracted from persimmon pickles in soy sauce and soy paste were gradually decreased to the 20th day of storage and then decreased rapidly, but the contents of water soluble material extracted from persimmon pickles in soy sauce and soy paste was increased during the storage time $(0{\sim}50\;days)$. The contents of lignin, pectin and acid-soluble hemicellulose of persimmon pickles in soy sauce and soy paste were decreased during the storage, but contents of alkali-soluble hemicellulose was increased. The contents of cellulose almost did not change during storage of pickles. The hardness of persimmon pickles in soy sauce and soy paste was gradually increased up to the 30th day of storage and then decreased. The activities of polygalacturonase and pectinesterase as softening enzyme in persimmon pickles with soy sauce and soy paste increased during storage. And ${\beta}-galactosidase$ activity was slightly increased to the 30th day of storage and after increased rapidly.

• Journal of Sericultural and Entomological Science
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• v.41 no.1
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• pp.54-60
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• 1999

Antheraea pernyi silk powder was prepared by treatment with HCl and NaOH. The degree of hydrolysis of Antheraea pernyi silk fiber was examined. The morphology and structural characteristics of Antheraea pernyi silk powder were investigated by using SEM, FTIR and X-ray diffractometer. As the concentration of HCl and NaOH and tratment temperature increased, in general, the degree of hydrolysis of Antheraea pernyi silk fiber increased. On the other hand, the degree of hydrolysis of Antheraea pernyi treated with 3 N NaOH at 120$^{\circ}C$ for 24 hr was 70 wt%, which was lower than that of 90$^{\circ}C$(83 wt%). The morphology of acid/alkali resistance fraction of Antheraea pernyi silk fibroin was transformed from fiber form to powered one with an increase of hydrolysis. The conformation of Antheraea pernyi silk powder characterized by FT-IR spectrometer and X-ray diffractometer ${\beta}$-sheet and ${\alpha}$-helix structure.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.41-50
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• 2022

Recently, research on carbon adsorbents has been active as an interest in improving the environment such as indoor and outdoor air quality. Considering that causative substances deteriorate the air quality are basically volatile organic compounds, it is important to improve the hydrophobicity of the carbon materials for better removal efficiency. This study presents a method for improving hydrophobicity of carbon and a measurement of the hydrophobicity. Generally, methods of improving the hydrophobicity of carbon materials are heat treatment, acid/alkali treatment, coating and immersion with hydrophobic materials. However, it collapses the pore structure and reduces the adsorption capacity. Therefore, this study briefly introduce not only the general method for improving carbon materials' hydrophobicity but also the method for converting the precursor of the material is briefly introduced. Futhermore, this study introduces a analytical technique used to determine hydrophobic modification or not, and aims to enhance the understanding of carbon materials.