• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1359-1366
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• 2004

Ultra high temperature treated (UHT) skim milk and colloidal calcium phosphate-free skim milk were treated with microbial transglutaminase (TGase), ultracentrifuged at various rates, lyophilized, and observed for morphological properties with a scanning electron microscope (SEM). UHT skim milk showed small holes of associated micelles at lower centrifugal rates, and became thick and irregular, and fine particles were associated regularly at higher centrifugal rates. When UHT skim milk with TGase was incubated for 1 hour, casein micelles aggregated and broadened as centrifugation rate increased. When UHT skim milk with TGase was incubated for 8 hours, casein micelles were associated irregularly to large aggregates and widened. Colloidal calcium phosphate-free skim milk with TGase incubated for 1 hour and separated by two-step centrifugation showed aggregated lump, while the milk incubated for 8 hours with TGase was associated with broadened, compact, and regular layers as the centrifugation rate increased. Such phenomena were caused by heat treatment, protein crosslinking reaction catalyzed by TGase and conformational changes of casein molecules, and could be dependent on reaction time, temperature and ultracentrifugation rate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.586-591
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• 2000

This study was conducted to investigate the effect on quality of low fat pork patties containing various hydrocoloids such as sodium alginate, carboxymethy1 cellulose (CMC) and zanthan gum. Moisture contents of raw, cooked and reheated patties of control patty (20% fat) were lower than those of the hydrocolloids-added patties, and fat content patties was higher than other patties. Colors of raw and reheated patties were not different among four kinds of patties, but L-value of cooked patty adding sodium alginate and b-value of control patty were low significantly in comparison with other patties. Cooking and final yield of hydrocolloids-added patties was high significantly in comparison with control patty. Fat retention of cooked control patty was lower than hydrocolloids-added patties, and fat retentions of retention four kinds of patties were 89.7~93.1%. Hardness of cooked and reheated patties adding xanthan gum was low significantly in comparison with other patties, and chewiness was high in theorder of control patty, CMC, sodium alginate and xanthan gum. In case of water holding capacity, cooked and reheated hydrocolloids-added patties, and juiciness was superior in the order of xanthan gum, sodium alginate, CMC and control patty. On the whole, textural and sensory characteristics of patties containing hydrocolloids were superior to control patty.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1253-1261
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• 2003

This study was carried out to investigate the influences of hydrocolloids on suppression of retrogradation in the Korean rice cake. Hydrocolloids were influenced to the textural characteristics of the Korean rice cake. In particular arabic gum and carrageenan had the effect of suppressing the retrogradation. Cohesiveness of the Korean rice cake added with hydrocolloids was shown to be high compared to control in organoleptic characteristics. Hydrocolloids exhibited slightly effective in retarding surface color change of the Korean rice cake. Onset temperature of gelatinization in thermal characteristics showed somewhat low in case of addition of arabic gum into the Korean rice cake and was followed by carrageenan, guar gum, gelatin and locust bean gum in onset temperature of gelatinization order. All samples added with hydrocolloids had low values in change of melting enthalphy and their range was 12.8 ∼ 17.7 J/g. The Korean rice cake added with arabic gum was lowest in melting enthalphy. The recrystallinity of the Korean rice cake added with arabic gum was greatly low compared to rice cake without hydrocolloids. Melting spreadability of the Korean rice cake added with arabic gum or carrageenan was superior in thermal characteristics. The value of exponent of Avrami was 0.97 ∼ 1.12 in study of Avrami equation. In conclusion carrageenan and arabic gum would have a suppressive effect of retrogradation in the Korean rice cake.

• Membrane Journal
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• v.21 no.1
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• pp.84-90
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• 2011

We studied the effects of induction of natural convection instability flow (NCIF) according to the gravitational orientation (inclined angle) of the membrane cell on the reduction of membrane fouling in ultrafiltration (UF) of colloidal silica solutions. Five colloidal silica solutions with different silica size (average size = 7, 12, 22, 50 and 78 nm) were used as UF test solutions. The silica particles in colloidal solutions form cakes on the membrane surface thereby causing severe reduction in the flux. The UF performance according to the gravitational orientation of the membrane cell (from 0 to $180^{\circ}$ inclined angle), was examined in an unstirred dead-end cell. We evaluate the effects of NCIF on membrane performance as the flux enhancement ($E_i$). In the dead-end UF of smaller size (7, 12 and 22 nm) silica colloidal solutions, changing the gravitational orientation (inclined angle) of the membrane cell induces NCIF in the membrane module and higher inclined angle and smaller size silica colloidal solution offer more stronger NCIF. This induced NCIF enhances back transport of the deposited silica solutes away from the membrane surface, therefore gives for the improvement of permeate flux. But in UF of more larger size (50 and 78 nm) silica colloidal solutions, NCIF effects are not appearing. These results suggest that the size of colloidal particle affects the extent of NCIF occurrence.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.11
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• pp.735-742
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• 2012

This study tried to find a suitable method for enhancing the foam stability of cationic surfactants that normally generate less foam or no foam. Several trials were made to enhance the foam stability: addition of anionic surfactant, colloids and polymer. Cationic starch (CA-ST) did not form foam at all, while the foam stability of two other cationic surfactant also showed low levels; methyl triethanol ammonium methyl sulfate distearyl ester (CEQ90) for 46 sec. and Cetyl trimethyl ammonium chloride (CM29) for 31 seconds. Foam stability of cationic surfactants were significantly affected by addition of anionic surfactant, sodium dodecyl sulfate (SDS). Foam stability of CA-ST was significantly enhanced by addition of SDS, while those of CEQ90 and CM29 were decreased. Addition of colloids ($SiO_2$, kaolin) and polyvinyl alcohol (PVA) enhanced foam stabilities of CEQ90 and CM29. However, CA-ST did not form foam even in the presence of colloids or PVA. Effect of simultaneous addition of colloids and anionic surfactant on foam stability of cationic surfactant showed that foam stability of cationic surfactant was more influenced by addition of anionic surfactant than colloids. Effect of simultaneous addition of PVA and anionic surfactant on the foam stability of cationic surfactant also showed that presence of anionic surfactant significantly affect the foam stability of cationic surfactant. Foam stability of CA-ST was greatly increased to 8,780 seconds by addition of SDS 0.14% and PVA 2.5%. The foam stability of CA-ST was 8 times higher than CEQ 90. This study suggested that cationic surfactants not forming foam can generate foam by addition of anionic surfactant and its stability can be additionally increased by addition of colloids and PVA. The study results showed that enhancement in foam stability of cationic surfactant was prominently affected by the concentration of anionic surfactant added.

• Polymer Science and Technology
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• v.15 no.1
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• pp.48-61
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• 2004

• Textile Coloration and Finishing
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• v.5 no.3
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• pp.250-259
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• 1993

• Polymer Science and Technology
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• v.25 no.1
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• pp.21-27
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• 2014

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.247-247
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• 2003

• Electrical & Electronic Materials
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• v.31 no.4
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• pp.27-33
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• 2018