• Korean Journal of Food Science and Technology
• /
• v.16 no.4
• /
• pp.429-436
• /
• 1984

To expand the utility of barley the experiments on the extrusion characteristics of barley flour for snack processing were carried out and the effects of the extrusion conditions on the quality of the extrudates were investigated. The optimum moisture content of barley flour for snack processing was 20%. The moisture content and the density of the extrudates decreased with increasing extrusion temperature and decreasing die size. The die swell ranged from 0.98 to 2.18 according to various extrusion conditions and decreased with increasing temperature above $150^{\circ}C$. The lightness, redness and yellowness increased at higher temperature. The water absorption index and the water solubility index showed their maximum values at $180^{\circ}C$.The gelatinization degree of the extrudates increased with increasing temperature. The fracture fore, Young's modulus and maximum fiber stress decreased, but the deformation to fracture increased, with increasing temperature and decreasing die size. The yield force in puncture test showed lower values at higher temperature. The size and the fraction of the air cells increased with increasing temperature and decreasing die size. The optimum extrusion conditions of barley for snack processing were at the temperature of $180^{\circ}C$, with the die size of 4.5mm when processed at 160 rpm.

• Korean journal of food and cookery science
• /
• v.7 no.4
• /
• pp.63-69
• /
• 1991

This study was undertaken for the purpose of studying the physicochemical propery of mungbean and texture of mungbean starch gels. Mungbean starch gel made with different levels of oil were tested to investigate the textural characteristics by mechanical test. The results are summerized as fallows: The content of moisture fat, protein, and ash in Seonwha mungbean were shown to be about 13.19%, 1.02%, 23.57% 3.13% respectively. Those of Seonwha mungbean crude starch were 12.48%, 0.63%, 0.94%, 0.13% respectively. The gain of dry crude starch from peeled mungbean was 22.48%. Water binding capacity of Seonwha mungbean crude starch was 183.1%. The pattern of change in swelling power of Seonwha mungbean crude starch for increasing temperature increased slowly to $70^{\circ}C$, and then increased rapidly. The pattern of change in solubility was similar to that of swelling power. The amylose and amylopectin content were 22.5%, 77.5%. Brabender hot-paste viscosities of mungbean crude starch at 8% and 10% showed the similar amylogram patterns with peak vicosity. By the Rheometer measurement result of 8% 10% mungbean starch gel, Hardness and Fractuability tended to be decreased as the addition level of oil increased. Elasticity, Adhesiveness, Chewiness, L, a, and b value tended to be increased as the addition level of oil increased.

• Journal of Sericultural and Entomological Science
• /
• v.13 no.1
• /
• pp.61-67
• /
• 1971

This experiment was conducted to know the effects of abnormal cocoons on the silk quality during the silk reeling process. The results obtained are summarized as follows: 1. The length, the width, the weight, the layer weight, and the layer ratio of abnormal cocoons are in every case 0.83∼4.65% less than those of normal cocoons. 2. The thickness of the abnormal cocoon layer is at)out 20.62∼22.4% less than that of the normal cocoon. 3. The sericin solubility of tile abnormal cocoon layer is about 11.75∼30% more than that of the normal cocoon layer. 4. The degumming ratio of the abnormal cocoon layer is about 6.51∼9.32% more than that of the normal cocoon layer. 5. The length of a have, the weight of a tave and percentage of raw silk yield of the abnormal cocoon are decreased 9.43%, 8.53% and 6.72% each as compared with those of the normal cocoon. 6. The percentage of reelability of abnormal cocoons is decreased 9.58％ as compared with that of normal cocoons. 7. The neatness of abnormal cocoons is 3 per cent lower than that of normal cocoons. 8. In the cleanness test of abnormal cocoons, the number of split ends i9 about 1.5∼3.8 times as much as that of normal cocoons. Especially cleanness of abnormal cocoons is 16,3 per cent lower than that of normal cocoons. 9. The number of non-reelable cocoons of abnormal cocoons is increased 1.4∼5.5 times as much as that of normal cocoons. In abnormal cocoon, the number of knot which resulted in the breaking of silk end is increased 1.9∼3.5 times as much as that in normal cocoon.

• Korean Journal of Food Science and Technology
• /
• v.29 no.5
• /
• pp.888-894
• /
• 1997

Two hulled and two hull-less barley varieties were investigated for ${\beta}-glucan$ enrichment. Hull-less barleys contained higher levels of total ${\beta}-glucan$ than hulled barleys, and were thus suitable as starting materials for preparing ${\beta}-glucan-rich$ fractions. Particularly, a waxy type (Suweon-291) of hull-less barley was found to have high soluble dietary fiber content containing primarily ${\beta}-glucan$, compared to the other non-waxy barley varieties. ${\beta}-Glucan$ content of barley during pearling process was measured, and the highest value was observed at the pearling yield of approximately $70{\sim}75%$. The pearled barley grains were ground and sieved to yield ${\beta}-Glucan$ enriched fractions containing up to 22% ${\beta}-glucan$. In the meanwhile, whole barley samples were directly milled by $B{\ddot{u}}hler$ mill to produce bran, shorts, break flour and reduction flour. ${\beta}-Glucan$ contents in the bran and shorts from the milled stream were relatively high, and further concentration of ${\beta}-glucan$ could be accomplished by successive sieving of the bran and shorts fractions. Pearled barley and milled stream could be used to prepare barley fractions with ${\beta}-glucan$ concentrations $2.4{\sim}3.1$ times those of the original barley grain. Water solubility of barley ${\beta}-glucan$ from pearled barley and the milled stream was in the range of $40{\sim}81%$.

• The Korean Journal of Pesticide Science
• /
• v.15 no.4
• /
• pp.441-452
• /
• 2011

This study was carried out to survey the residual characteristics of endocrine disruptor (ED)-suspected pesticides in greenhouse soils and assess their leachabilites to groundwater. Greenhouse soils were collected from 40 sites of greenhouse in 2008 in Korea. Sixteen ED-suspected pesticides which had been using in Korea, such as alachlor, benomyl, carbaryl, cypermethrin, 2,4-D, dicofol, endosulfan, fenvalerate, malathion, mancozeb, metribuzin, metiram, methomyl, parathion, trifluralin, and vinclozolin, in the soils, were analyzed by chromatographic methods using GLC-ECD and HPLC-DAD/FLD. Limits of detection (LODs) of the test pesticides ranged from 0.0004 to 0.005 mg/kg. Recoveries of the target pesticides from soil ranged from 72.69 to 115.28%. Four pesticides including cypermethrin were detected in the range of from 0.001 to 2.019 mg/kg, representing that their detection rate from greenhouse soils was 37.5%. The highest detection rate was observed from endosulfan which was detected from 16 site soils of the total samples, indicating that endosulfan is persistent in soil because of its very low mobility and high adsorption characteristics in soil. Based on the groundwater ubiquity scores (GUSs) of the pesticides detected from greenhouse soils, most of them have little possibilities of groundwater contamination except the fungicide vinclozolin with some leaching potential because of high water solubility and very low soil adsorption property.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.32 no.2
• /
• pp.175-179
• /
• 1999

Processing conditions for dried condiments with oyster, pen shell and cockle shell were investigated. The enzymatic hydrolysis for 3 hours was more profitable than hydrothermal extraction to develop flavoring matters from oyster, pen shell and cockle shell. As a result of omission tests, nucleotides were predominated in the taste compounds of shellfish hydrolysates rather than free amino acids, and the contribution of nucleotides and free amino acids to the taste of shellfish hydrolysates was remarkable. The major flavoring components of shellfish hydrolysates were free amino acids and oligopeptides below 500 dalton. When shellfish hydrolysates were separated with membrane (molecular weight cutoff 500 dalton) for recovering flayer, recovering yields of amino type nitrogen were $92.1\~92.8\%$. Moisture contents of dried shellfish condiments prepared with pretense hydrolyzed oyster, pen shell and cockle shell were $3.5\%,\;3.8\%$ and $3.7\%$, respectively. Contents of total nitrogen were $69.4\%,\;78.8\%$ and $74.2\%$, and those of amino nitrogen were $45.5\%,\;48.9\%$ and $45.4\%$, respectively. Drying yield, solubility and absorption rates at Aw 0.88 were $11.7\%,\;78.4\%$ and $6.8\%$ in oyster, $8.2\%,\;73.6\%$ and $6.1\%$ in pen shell, $9.8\%,\;76.9\%$ and $6.6\%$ in cockle shell, respectively.

• Journal of Environmental Health Sciences
• /
• v.27 no.2
• /
• pp.108-118
• /
• 2001

This study was performed to investigate the bioconcentration of IBP, methidathion and piperophos. The BCFs(bioconcentration factor), depuration rate constants for three pesticides in zebrafish(Brachydanio rerio) were measured by OECD guideline 305. The concentration of test pesicides were one-hundredth and one-thousandth concentration of 96-hrs L $C_{50}$ in accordance with OECD guideline 305. The results obtained are summarized as follows: The average BCF values of IBP were 5.31(n=4) and 7.30(n=4) at one-hundredth and one-thousandth concentration of 96-hrs L $C_{50}$ . The average BCF values of methidathion were 8.72(n=4) and 11.25(n=4), the average BCF values of piperophos were 34.30(n=4) and 42.60(n=4). Depuration rate constants of IBP were 0.09( $h^{-1}$ ) and 0.08( $h^{-1}$ ), half-life of IBP were 7.70 and 8.66 at each tested concentration. The concentrations of IBP in zebrafish at low and high concentrations rapidly decreased after 12(0.243$\mu\textrm{g}$/g) and 12 hours(0.040$\mu\textrm{g}$/g). Depuration rate constants of methidathion were 0.40( $h^{-1}$ ), half-life of methidathion were 1.73 at one-hunderdth and of 96-hrs L $C_{50}$ , repectively. The concentrations of methidathion in zebrafish at high concentrations rapidly decreased after 6 hours(0.18 $\mu\textrm{g}$/g). Depuration rate constant of low concentration was no measured because methidathion in zebrafish was depurated in 6 hours. Depuration rate constants of piperophos sere 0.15( $h^{-1}$ ) and 0.44( $h^{-1}$ ), half-life of piperophos were 4.62 and 1.58 at each tested concentration. The concentrations of piperophos in zebrafish at los and high concentrations rapidly decreased after 12(0.26$\mu\textrm{g}$/g) and 6 hours(0.015 $\mu\textrm{g}$/g). It was suggested that high BCF of piperophos was due to high Kow(octanol-water partition coefficient). The possibility of bioconcenration was not likely to be high because of its $K_{DEP}$(depuration rate constant) in the evniroment. It was suggested that low BCF of methidathion showed lowest Kow as well as the most rapid $K_{DEP}$. Therefore, the possibility of bioconcentration was not occured in the enviroment. It was suggested that the BCF dtermined for IBP was lower than that of other pesticides due to high Sw(water solubility), show $K_{DEP}$. Therefore, IBP revealed little bioconcentration effect on in aquatic ecosystem.ystem.

• Restorative Dentistry and Endodontics
• /
• v.31 no.4
• /
• pp.290-299
• /
• 2006

Objectives: The purpose of this study is to evaluate the effect of ethylene glycol analogs on modulus of elasticity and ultimate tensile strength of moist, demineralized dentin matrix. Methods: Dentin disks 0.5 mrn thick were prepared from mid-coronal dentin of extracted. unerupted, human third molars. 'I' beam and hour-glass shaped specimens were prepared from the disks, the ends protected with nail varnish and the central regions completely demineralized in 0.5M EDTA for 5 days. Ultimate tensile stress (UTS) and low strain modulus of elasticity (E) were determined with specimens immersed for 60 min in distilled water $(H_{2}O)$, ethylene glycol $(HO-CH_{2}-CH_{2}-OH)$, 2-methoxyethanol $(H_{3}CO-CH_{2}-CH_{2}-OH)$, and 1,2-dimethoxyethane $(H_{3}CO-CH_{2}-CH_{3}-OCH_{3})$ prior to testing in those same media. Modulus of elasticity was measured on the same specimens in a repeated measures experimental design. The results were analyzed with a one-way ANOVA on ranks, followed by Dunn's test at ${\alpha}\;=\;0.05$. Regression analysis examined the relationship between UTS or E and hoy's solubility parameter for hydrogen bonding $({\delta}_{h})$ of each solvent. Results: The UTS of demineralized dentin in water, ethylene glycol, 2-methoxyethanol, and 1,2-dimethoxyethane was 24 (3), 30 (5), 37 (6), and 45 (6) MPa, ${\times}$ (SD) N = 10. Low strain E for the same media were 16 (13), 23 (14), 52 (24), and 62 (22) MPa. Regression analysis of UTS vs ${\delta}_{h}$ revealed a significant $(p\;<\;0.0001,\;r\;=\;-0.99,\;R^{2}\;=\;0.98)$ inverse, exponential relationship. A similar inverse relationship was obtained between low strain E vs ${\delta}_{h}\;(p\;<\;0.0005,\;r\;=\;-0.93,\;R^{2}\;=\;0.86)$. Significance: The tensile properties of demineralized dentin are dependent upon the hydrogen bonding ability of polar solvents $({\delta}_{h})$. Solvents with low ${\delta}_{h}$ values may permit new interpeptide H-bonding in collagen that increases its tensile properties. Solvents with high ${\delta}_{h}$ values prevent the development of these new interpeptide H-bonds.

• Korean Journal of Materials Research
• /
• v.11 no.2
• /
• pp.104-114
• /
• 2001

To investigate the effects of the addition of Nb and Sn on the recrystallization of Zr- Sn-Nb alloys, both Vickers micro-hardness test and TEP measurement were carried out on cold-worked specimens annealed at various temperatures from $300^{\circ}C$ to 75$0^{\circ}C$. The microstructures of heat treated specimens were analyzed by optical microscope, SEM, and TEM. The study of microhardness and microstructures showed that both recrystallization process and grain growth were retarded as the activation energy was increased by the addition of Nb and Sn. Especially, the addition of Sn was more effective on retarding recrystallization. Precipitates were formed more easily when Nb was added because the solubility of Nb into Zr is lower than that of Sn. However, the recrystallization process was affected more by Sn than Nb because the strain field formed by substitutional Sn repressed the dislocation movement. TEP was increased due to the decrease of electron scattering as recovery and recrystallization were proceeded and saturated when the recrystallization completed. However, when precipitates formed, TEP was increased because the decrease of solute concentration near the precipitates caused the decrease of electron scattering.

• Korean journal of food and cookery science
• /
• v.22 no.5 s.95
• /
• pp.659-665
• /
• 2006

The effects of resistant starches on the quality characteristics of cookies were investigated by the physicochemical, instrumental and sensory properties of RS-added flours and cookies. Retrograded RS3 by autoclaving-cooling cycle and cross-linked RS4 after annealing treatment were used. The protein content of RS-added flour decreased, but the ash content of RS4-added flour increased slightly with increasing RS content. The RS levels of wheat flour, RS3- and RS4-added flours were 7.0%, 9.6-13.4% and 11.5-17.9%, respectively. The swelling powers of RS-added flours at 80$^{\circ}C$ decreased, but the solubility of RS3-added flour increased by 2-3 fold compared to that of control flour. Initial pasting temperature increased, but peak, holding, and final viscosities decreased with increasing RS content. The retrogradation degree of RS-added flours was lowered, because of the decreased consistency and breakdown viscosity. The yellowness of RS3-added flour increased with increasing RS3 content which induced browning reaction during baking. On the sensory test, RS-added cookies were significantly different in shape, color and overall quality (p<0.05), and their texture also affected. Overall quality was higher in peanut cookies than in AACC standard cookies and RS addition (up to 30%, w/w), regardless of the RS type, improved the cookie quality.