• Asian-Australasian Journal of Animal Sciences
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• v.26 no.4
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• pp.537-544
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• 2013

This study examined whether pre-treating palm kernel expeller (PKE) with exogenous enzyme would degrade its fiber content; thus improving its metabolizable energy (ME), growth performance, villus height and digesta viscosity in broiler chickens fed diets containing PKE. Our results showed that enzyme treatment decreased (p<0.05) hemicellulose and cellulose contents of PKE by 26.26 and 32.62%, respectively; and improved true ME (TME) and its nitrogen corrected value ($TME_n$) by 38% and 33%, respectively, compared to the raw sample. Average daily gain (ADG), feed intake and feed conversion ratio (FCR) of chickens fed on different dietary treatments in the grower period were not significantly different. Although there was no difference in feed intake (p>0.05) among treatment groups in the finisher period, ADG of chickens in the control (PKE-free diet) was higher (p<0.05) than in all treatment groups fed either 20 or 30% PKE, irrespective of with or without enzyme treatment. However, ADG of birds fed with 20% PKE was higher than those fed with 30% PKE. The FCR of chickens in the control was the lowest (2.20) but not significantly different from those fed 20% PKE diets while birds in the 30% PKE diets recorded higher (p>0.05) FCR. The intestinal villus height and crypt depth (duodenum, jejunum and ileum) were not different (p>0.05) among treatments except for duodenal crypt depth. The villus height and crypt depth of birds in enzyme treated PKE diets were higher (p<0.05) than those in the raw PKE groups. Viscosity of the intestinal digesta was not different (p>0.05) among treatments. Results of this study suggest that exogenous enzyme is effective in hydrolyzing the fiber (hemicellulose and cellulose) component and improved the ME values of PKE, however, the above positive effects were not reflected in the growth performance in broiler chickens fed the enzyme treated PKE compared to those received raw PKE. The results suggest that PKE can be included up to 5% in the grower diet and 20% in the finisher diet without any significant negative effect on FCR in broiler chickens.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.414-420
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• 2014

This study was performed to increase the yield and to reduce the processing times for the preparation to improve the productivity and quality of rice jochung, a traditional food in Korea. In order to evaluate the quality characteristics and yield of jochung, the viscosity, color value, mineral contents and the sensory evaluation were measured. Jochung is prepared from steamed rice (STR), wet-milled rice flour (WRF) and dry-milled rice flour (DRF) by processing methods of rice and reacting times (6 hours or 13 hours) of liquefaction and saccharification. There is commonly added liquefying enzyme for rice liquefaction (0.4%/10 kg rice, at $85{\sim}90^{\circ}C$ for 1 hour or 4 hours) and saccharogenic enzyme with malt (2.5% or 4.5%/10 kg rice, at $56{\sim}60^{\circ}C$ for 5 hours or 9 hours). The inner structural properties of WRF showed the more distinct shape regular structure of uncombined starch particles but the DRF closely maintained particles of rice flour observed by SEM. If processing times for liquefation and saccharification were reduced from 13 hours to 6 hours, the yield of jochungs prepared with WRF increased 8%, the DRF 7%, and the STR 3% respectively and the sensory evaluation as well as color values and overall desirability received high scores. The viscosity, color a and b values of jochung processed with WRF for 6 hours were lower than that processed for 13 hours. The viscosity and color a, b value and Ca content were decreased in the jochung processed with WRF or DRF for 6 hours, but Mg, P and K were increased than that of STR. Jochung processed by 0.4% liquefying enzyme and 2.5% malt with WRF for 6 hours will increase the yield, save manufacturing times and costs and will thereby enable cost-effective techniques.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.162-169
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• 2013

We determined the optimum pretreatment conditions such as pH and time for swelling duck feet and investigated the effects of the extracting method, such as water bath (WB), pressure cooker (PC), and microwave oven (MO), on quality characteristics of the duck feet gelatin for improving utilization of duck feet as a novel source of gelatin. The soaking solution of pH 1 among pH 1-14 with unit intervals was selected due to the highest yield. The quality characteristics of the gelatin tested were color, pH, gel strength, viscosity, and melting point. For the extracted gelatin with different methods, the CIE $L^*$, $a^*$ and $b^*$ values were in the following order: MO>PC>WB (p<0.05), WB>PC>MO (p<0.05) and PC>MO>WB (p<0.05), respectively. The gelatin extracted using WB showed the highest pH and that extracted using MO showed the lowest pH (p<0.05). The gel strength, viscosity, and melting point were the highest for MO (p<0.05). The gel strength and melting point were the lowest for PC (p<0.05). No significant difference was found in viscosity between the gelatins extracted using WB and PC (p>0.05). The quality characteristic of duck feet gelatin was affected by extracting methods, and MO extraction can be one of the effective methods for duck feet gelatin.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.542-547
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• 1998

Polyamine type polymer flocculants were synthesized and their characterization, viscosity and flocculation studies were conducted. In order to increase the molecular weight of polyamine flocculant which was prepared by polycondensation reaction from dimethylamine and epichlorohydrin, a small amount of 1,6-hexanediamine was employed. The incorporation of 1,6-hexanediamine up to 5.5 mole % replacing corresponding part of dimethylamine gave a branched type polyamine sample with increased intrinsic viscosity ([${\eta}$]=0.46 in 1 wt % aqueous NaCl solution). The amount of 1,6-hexanediamine above 5.5 mole %, however, resulted in gelation during polymerization. Utilizing raw water from Maegok potable water treatment plant, it was found that the addition of polyamine flocculant at a concentration of 1 mg/L level could reduce the amount of polyaluminum chloride (PAC) inorganic flocculant by half (15 mg/L). It was also observed that the incoporation of polyamine flocculant at 1 mg/L level was effective in the higher pH raw water, while PAC inorganic flocculating agent alone was not effective.

• Clean Technology
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• v.7 no.4
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• pp.281-290
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• 2001

A microwave-assisted process to prepare chitosan from natural crabshells has been investigated. This study was primarily to examine the effectiveness of microwave as clean energy for chitosan preparation. Several human-edible organic acids were used as clean catalyst, possibly to improve the current HCl-based hydrolysis process of polymeric chitosan. The microwave was found to be effective substantially in reducing the reaction time. Nonetheless, no beneficial effect of microwave other than time, such as the chemical selectivity, was hardly observed. The organic acids were very effective in the hydrolysis reaction of polymeric chitosan. Their catalytic behavior was greatly improved especially when reactions were performed under pressure. In the case of autoclave reaction for 60 minutes at $120^{\circ}C$, viscous solution of polymeric chitosan (mol. wt. > 300,000) turned into thin solutions of water-like viscosity, which means chitosan molecules were decomposed to very small-sized oligomers.

• Journal of Soil and Groundwater Environment
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• v.17 no.6
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• pp.102-111
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• 2012

Fine suspended solids generated effluence from treatment process of mine drainage could destroy environment as the aesthetic landscapes, and depreciate water quality. Therefore, the purpose of this research is focused on process development applied the actual field for controlling fine suspended solids and heavy metals, and so lab-scale test was performed for inducement of basic data. The mine drainage used in this research was sampled in H mine located Jeongseon-gun, Gangwon-do. Concentration of suspended solid, arsenic, iron and manganese was exceeded the standard of contaminant limitation for the clean water, and particle size of suspended solid was less than 10 m as fine particle. Although hydraulic retention time of mine drainage for effective settling was required more than 6 hours, hydraulic retention time would be increased in winter season when the settling efficiency could be reduced because of viscosity decreasing. Moreover, installed inclination plate helped to increase settling efficiency of suspended solid about 48 %. Filtering media that was the most effective removal of suspended solids and heavy metal was decided granular activated carbon of 1~2 mm was the optimal size.

• Korean journal of food and cookery science
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• v.15 no.1
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• pp.73-80
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• 1999

This study was carried out to investigate the effects of enzyme treatments on the functional properties of soy protein isolate (SPI) and to examine the quality attributes of soy yogurt prepared by different enzyme treatments, sweeteners and starter cultures. Enzyme treatment increased the solubility and emulsifying capacity of soy proteins, but decreased the emulsifying stability; the enzymatic activity of ${\alpha}$-chymotrypsin was higher than that of trypsin. Enzyme treatments decreased the pH of soy yogurts prepared by both culture methods, the culture of L. bulgaricus and S. thermophilus and the culture of L. bulgaricus and K. fragilis, but increased the titratable acidity, total numbers of lactic acid bacteria and yeast. Trypsin was more effective than ${\alpha}$-chymotrypsin in decreasing pH and increasing titratable acidity and total numbers of lactic acid bacteria and yeast. Fructose decreased the pH of soy yogurts more than sucrose in the culture of L. bulgaricus and S. thermophilus, and vice versa in the culture of L. bulgaricus and K. fragilis. Fructooligosaccharides were more effective in the culture of L. bulgaricus and K. fragilis than in the culture of L. bulgaricus and S. thermophilus in increasing the titratable acidity, total count of lactic acid bacteria and yeast. In sensory evaluation, soy yogurts containing trypsin treated SPI, fructose and fructooligosaccharides (75%:25%) were more acceptable than those containing untreated or trypsin treated SPI and fructose. This was because of more smooth and less sour, in which the values of pH, titratable acidity, microbial growth, and viscosity were in the range of commercial yogurts. Soy yogurts fermented by L. bulgaricus and K. fragilis showed more smooth mouthfeel than those fermented by L. bulgaricus and S. thermophilus.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.977-983
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• 1999

This study was conducted to investigate the effects of emulsifiers on the quality of steamed bread. initial pasting temperature of the flour was decreased from $63.8^{\circ}C$ to $59.40{\sim}62.95^{\circ}C$ by adding 1% of emulsifiers such as monoglyceride, lecithin, sugar ester and diacetyl tartaric acid esters of mono- and diglycerides (DATEM). But other rheological properties of the doughs were varied with different emulsifiers. Flour with 1% sugar ester showed the lowest value of final viscosity and set back, therefore sugar ester might be effective for retard the retrogradation of bread. By alveogram test, flour with 1% DATEM showed the highest value of P (tenacity) but the lowest value of L (extensibility), that means DATEM might be effective for strengthening tenacity of dough but it lowered extensibility. After 72 hours of storage test, the steamed bread based on the flour with 1% monoglyceride showed the best crumb softness and the highest score of sensory test.

• Journal of Soil and Groundwater Environment
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• v.18 no.4
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• pp.1-7
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• 2013

Subcritical water which acts as organic solvent with increasing temperature and pressure because dielectric constant and viscosity decrease can be used to remediate PAHs-contaminated soil. Factors influencing on extraction were studied with varying the water temperature $200{\sim}275^{\circ}C$, extraction time 0~90 min, flow rate 10~100 mL/min and pressure 3.9~10MPa. 300 g of soil sample which was contaminated with PAHs(naphthalene, phenanthrene, fluoranthene and pyrene; 423, 420, 539 and 428 mg/kg of initial concentration) was packed into the cell and placed to reactor and then the subcritical water was pumped through the cell for PAHs extraction. Naphthalene was removed almost 100% at relatively low temperature ($200^{\circ}C$). The removal rate of phenanthrene, fluoranthene, and pyrene increased by 8, 26, and 23% when the temperature increased from 200 to $275^{\circ}C$; and it was gradually increased as extraction time increased from 0 to 90 min. Decreasing removal rate when water flow rate increased from 10 to 30 mL/min, but there was no significant change after 30 mL/min. This is supposed due to channeling phenomenon. The pressure was not an effective factor for extraction of PAHs in this study. Based on the results, the importance of effective factor was in following sequence: temperature >> time > flow rate.

• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.445-450
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• 1992

An enhancement of the oxygen transfer rate in a 1$\ell$ bioreactor for mammalian cell culture by using a silicone rubber tubing as an oxygenator was investigated. When the silicone membrane was used to supply oxygen to the culture broth, the oxygen transfer coefficients ($k_{\iota}a$) measured in deionized-distilled water were markedly increased. Effect of surface aeration without the tubing aeration was very low under $1.0hr^{-1}$ of $k_{\iota}a$. The enhancing effects of agitation rates on $k_{\iota}a$ were much more effective than those of aeration rates. The increase of $k_{\iota}a$ with increasing tube length was observed as a result of the large surface area for oxygen supply. However, 2 m of the tube length was adequate for a 1$\ell$ vessel. The larger blade type of impeller was effective to enhance the kLa values because of its high mixing intensity. In culture medium supplemented with 5% serum, kLa values were reduced to approximately 40% probably due to the viscosity. We also obtained the normal cell concentration of $5{\times}10^6$ cells/m$\ell$ of HepG2 on microcarriers, which could be achieved in a typical bioreactor for animal cell culture.