• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.138-143
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• 1977

Physicochemical properties of buckwheat starch were investigated. Starch granules were in the range of $4.3{\sim}11.4$ microns in size, the average being 7.8 microns. The starch had a water-binding capacity value of 103.7%, blue value of 0.35 and amylose content of 25%. The initial and final gelatinization temperatures were $61^{\circ}$ and $65^{\circ}C$, respectively. Amylograph data showed that the starch had an initial pasting temperature of $64.5^{\circ}C$. The kinetic study of crystallization of buckwheat starch during aging at $21^{\circ}C$ suggested that the mechanism of starch crystallization is instantaneous nucleation followed by rod-like growth of crystals.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.5
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• pp.54-62
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• 2012

The main role of surface sizing of linerboard is to improve surface and strength properties. Since surface sizing solution is applied on once dried web, substantial amount of drying energy is required. Saving of the drying energy associated with surface sizing can be made by increasing the solids content of the starch solution in size press. Therefore, it is highly desirable to develop low viscosity starches for surface sizing. A low viscosity oxidized starch was prepared and compared its effect of surface sizing with a conventional oxidised starch. Results showed increase in solids content of the starch solution decreased evaporation energy and drying time. Low viscosity starch penetrated deeper into paper and this improve various mechanical properties of linerboard.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.7
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• pp.79-86
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• 2010

The environment-friendly abrasive materials of starch series has a wide range of application value such as deburring of plastic injection products, paint exfoliation and surface treatment of painted products and polishing, etc. In this study, an experiment of paint exfoliation was performed by using the environment-friendly abrasive materials made of cheap starch, and its performance was reviewed. By adjusting the grit size of abrasive materials, nozzle pressure, nozzle feed and number of nozzle repetition, paint could be exfoliated effectively. In this experiment, it was found that the most suitable condition was grit size 0.75~1.0 mm, nozzle pressure 0.4 MPa, nozzle feed 5 mm/min and number of processing repetition 2 times.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.11
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• pp.1615-1622
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• 2011

A factorial ($4{\times}2{\times}2$) experimental design was employed to determine apparent digestibilities of dry matter (DM), protein, lipid, energy and nitrogen-free extract (NFE) of the test diets containing either ${\alpha}$-potato starch (A-PS), ${\beta}$-potato starch (B-PS), ${\beta}$-corn starch (B-CS) or dextrin (DEX) as dietary carbohydrate energy for juvenile (average weight 30 g) and grower (average weight 300 g) rockfish reared at 13$^{\circ}C$ and 20$^{\circ}C$. Chromic oxide was used as an inert marker. Feces were collected by fecal collectors attached to rearing tanks from triplicate groups of juvenile and grower rockfish. Digestibilities of DM, energy and NFE of the test diets were significantly affected by dietary carbohydrate and water temperature (p<0.01), but not by fish size. DM digestibility of the fish fed the A-PS diet was significantly higher than that of fish fed other treatments, except for the DEX diet at 20$^{\circ}C$. DM digestibility of rockfish fed the B-CS diet was significantly lower than that of other diets. A similar pattern was observed in apparent digestibility of energy. NFE digestibility of fish fed the test diets was significantly affected by carbohydrate and significantly correlated to DM (r = 0.97, p<0.01) and energy (r = 0.99, p<0.01) digestibilities, regardless of water temperature and fish size. NFE digestibility of the fish fed the ${\beta}$-starch diets was relatively lower compared to that of the ${\alpha}$-starch diets, and ranged from 35 to 43% and 20 to 27% for B-PS and B-CS, respectively. The present findings indicate that carbohydrate and water temperature significantly affected digestibilities of dry matter, energy and nitrogen-free extract of rockfish. Among dietary carbohydrates, ${\alpha}$-potato starch could be effectively used as dietary carbohydrate energy for rockfish at 13$^{\circ}C$ and 20$^{\circ}C$.

• Applied Biological Chemistry
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• v.31 no.4
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• pp.339-345
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• 1988

Physicochemical properties of starch isolated from the naked barley seeds during germination were investigated, The germinated barley seeds showed an apparent increase in amylose component of the starches, and water binding capacities of the starches decreased initially and then increased with longer germination time. The size frequency distribution of starch granules showed that the granules larger than $20.2{\mu}$ in diameter were preferentially degraded, and moreover the rate of degradation was higher than that of granules of any other size. It was apparent that the mean diameter of granules was $12.7{\sim}20.2{\mu}$ at all stages of germination. The results of differential scanning calorimetry, swelling power, solubility and X-ray diffraction patterns of starch granules isolated at various stages of germination showed little changes during germination. Scanning electron microscopy revealed that the starch granules have been damaged extensively by degradative enzymes during germination, but all the starch granules were not degraded uniformly.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.292-294
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• 1998

Surimi sol and gel were prepared by mixing egg albumin, starch, oil and carrageenan, which are used as representative ingredients in the surimi composite, at different ratio. Structural properties in surimi composite were investigated by examining the phase changes and dispersion pattern (average particle size, size range and the averge number of particle) of the particulate ingredients in sol and gel with an image analyzer. A staining technique of the specimen containing egg albumin in surimi gel was developed by adjusting pH of a toluidine staining solution. Image analysis revealed that size and density of ingredient particles were function of the level and dispersion of ingredients except of starch-incorporated surimi gel which showed maximum particle size at 6%.

• Microbiology and Biotechnology Letters
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• v.14 no.5
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• pp.399-405
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• 1986

Corn starch was saccharified without cooking in an agitated bead reaction system. Uncooked corn starch was effectively hydrolyzed even at the concentration as high as 39%(w/v). After 24 hours. the extent of saccharification reached at 92%, which corresponds glucose concentration of 425g/L. Fed-batch feeding of starch was more effective than batch feeding for saccharification of uncooked corn starch. The composition of hydrolysated of uncooked starch was analyzed. which was composed of 95% glucose, 0.7% of maltose, and 4.5% of high saccharide, similar with that of cooked starch. The hydrolysate can be successfully utilized for HFCS manufacture. The starch liquefying and saccharifying enzyme was relatively stable even be the physical impact of the attrition-milling media. The enzyme stabilizer, $Ca^{++}$, played an essential role in preventing the enzyme deactivation caused by the physical impact.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.942-949
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• 2005

To improve the textural properties and stabilize the structure and gel matrix of non-waxy rice starch gels, non-waxy rice starch/gum mixture gels were prepared from various food gums, gum arabic, guar, algin, deacyl gellan, xanthan and gellan gums. The morphological and textural properties and freeze-thaw stability of their gels were compared. Rice starch/gum mixture gels with various gums formed a more homogeneous gel matrix with smaller particle size than rice starch gel without Em, but the trends differed depending on the gum types. The textural properties of rice starch/gum mixture gels were changed with the gum types. The shape of the rice starch/gum mixture gel matrix was desirable when mixed with gellan and algin. The textural properties of gels hardened in the rice starch/algin mixture gel and softened in the rice starch/algin mixture gel. The rice starch gels showed V-type crystallinity by x-ray diffractometer, but the peak at $2\theta$ = $20^{o}$ was decreased with increasing gum addition. The freeze-thaw stability increased with increasing gum addition. Gellan and algin were especially effective.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.85-90
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• 2006

Increasing the filler content of sheet improves the optical properties and printability of paper and provides an opportunity for saving production cost through fiber replacement with relatively low-priced filler. But increasing the filler content tends to decrease the strength of paper and filler retention. It also tends to deteriorate drainage on the paper machine. To overcome these problems, preflocculation technology of fillers may be employed. Many research efforts have been made on the properties of preflocculated filler, namely prefloc, whose size and size distribution were influenced by polymer type and shear level. But there is much to be investigated about the effect of the prefloc characteristics on the physical properties of paper. To evaluate the effect cationic polymers on the size and size distribution of preflocculated GCC and their shear stability, cationic PAM and cationic starch were used. The influence of the preflocculation on filler retention and its surface distribution, and the changes of physical and optical properties of handsheets affected by the characteristics of preflocs were examined. Filler distribution on sheet surface was also analyzed by EPMA. Results showed that cationic PAM formed large preflocs at low dosage. Cationic starch was required to add 15 times as much as cationic PAM to obtain the preflocs with similar size. But preflocs formed with cationic starch was superior in shear stability to those formed with cationic PAM. Filler preflocculation technology could provide an opportunity of increasing filler content significantly without loss in tensile strength. And increased filler contents could compensate brightness loss which often accompanies filler preflocculation. When excessively large preflocs were used, however, brightness loss rather than the improvement in tensile strength was predominant. Therefore it is of great importance to produce preflocs with proper size and shear stability for maximizing the improvement of physical properties of papers.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.2
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• pp.53-60
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• 2015

The effects of stirring speed during filler modification by dual polymers on flocculation and reflocculation of PCC (precipitated calcium carbonate) particles and its effect on handsheet properties were elucidated. PCC surface was modified by adsorbing A-PAM (anionic polyacrylamide) and C-starch (cationic starch) in series at various stirring speeds. It was found that increasing stirring speed during filler modification decreased the initial floc size of PCC. Continuous stirring with the same speed for filler modification resulted in the decrease of a floc size, eventually reached a steady state. The variations in a floc size was influenced by the stirring speed during filler modification: the lower the stirring speed during filler modification, the larger the floc size variations. Conclusively, the stability of PCC floc could be improved by increasing the stirring speed. In addition, the stirring speed influenced the handsheet properties. The smaller the PCC floc, the lower the strength of handseet. However, too much larger floc size also deteriorated paper strength. There exists an optimum floc size in term of paper strength which shall be controlled by stirring speed during filler modification.