• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.755-762
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• 2000

Physicochemical properties of commercial sweet potato starches manufactured by 7 different companies were investigated in comparison with corn and potato starches. Crude ash and protein content varied from 0.36 to 1.02%, and from 0.04 to 0.14% based on dry weight, respectively. The protein contents were relatively smaller than that of corn or potato starch. But whiteness of the sweet potato starches was less than that of corn or potato starch. Mean diameter of the sweet potato starch granules varied from 14.23 to $21.08\;{\mu}m$ depending on the company and all sweet potato starches showed bimodal size distributions. Pasting viscosity measured by Rapid Viscoanalyzer(RVA) also showed variations among the starches of different companies. The starch from D company in Korea had the lowest pasting temperature$(74.00^{\circ}C)$ whereas the starch from a phillippine company(P) did the highest one$(80.35^{\circ}C)$. The peak viscosity of sweet potato starches was higher than that of corn starch but lower than that of potato starch. The D company starch also showed the highest peak viscosity(2283 cp) among the starches tested. Paste breakdown by hot shearing ranged from 524 cp (S company) to 1279 cp (HL company). Textural properties of the starch gels appeared significantly different among the starches of different manufacturers. The greatest hardness of the gel was $137.90\;g_{f}$ at 1 day storage whereas the lowest value was $31.53\;g_{f}$. Except the starches from 2 companies (P and S), the sweet potato starches formed very soft and weak gels. P or S company starches formed the gels similar to potato starch. Syneresis by freeze-thawing treatments appeared less for sweet potato starch gels than that for corn starch gels, but greater than that for potato starch gel. The overall properties of the sweet potato starches varied by the manufacturing companies, and ranged between those of corn and potato starches.

• Microbiology and Biotechnology Letters
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• v.19 no.4
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• pp.315-318
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• 1991

- A bacterial strain No. S-76 which produced pullulanase powerfully was isolated frorn soil. The isolated bacterium was 0.4~$0.6\times 0.8$~1.4 $\mu\textrm{m}$ in size, gram negative, rods, motile and was identified as Aerornonas caviae by Bergey's manual of determinative bacteriology with various characteristics investigated. The highest yield of pullulanase of the strain was obtained by using the following medium: 1% pullulan, soluble starch or corn starch as a carbon sources and 0.5% yeast extract, peptone as nitrogen sources with an initial pH of 9.0. The optimal cutture conditions for production of pullulanase were at $32^{\circ}C$ for 2 days.

• Korean journal of food and cookery science
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• v.8 no.1
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• pp.1-7
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• 1992

Recently, plenty of imported Chinese Mungbean is sold, for Korean Mungbean is expensive. But they say, Chinese Mungean has less delicacy and cooking quality. Above all, in comparison with Korean and Chinese Mungbeans properties they are different - Chinese Mungbean grain is twice in dimension, Chinese Mungbean is white and Korean one is yellow in peeled grain color. They are similar in size shape with the microscope. With Amylograph of Brabender the viscosity of Korean Mungbean is gradually and continually increased until heating from $25^{\circ}C$ to $92.5^{\circ}C$ and cooling to $25^{\circ}C$ again, but the one of Chines Mungbean is increased suddenly in 74$^{\circ}C$ and shows the abrupt break-down phenomenon. This same phenomenon is shown in swelling with melting-pointer, In $25^{\circ}C$, the cooling temperature, Chinese Mungbean is measured to 1400 B.U and Korean one 1600 B.U. With color-meter of Richard S. Hunter, 12% gel of Korean Mungbean starch is clear but Chinese one white. The texture of 12% gel of Chinese Mungbean starch with Rheo-meter becomes hardened much more than Korea one. As a result of sensory-test, color, cohesiveness, and flavors of Korean gel is preferred overwhelmingly.

• Journal of Microbiology and Biotechnology
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• v.23 no.4
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• pp.489-498
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• 2013

A new Bacillus strain degrading starch, named Bacillus sp. UEB-S, was isolated from a southern Tunisian area. Amylase production using solid-state fermentation on millet, an inexpensive and available agro-resource, was investigated. Response surface methodology was applied to establish the relationship between enzyme production and four variables: inoculum size, moisture-to-millet ratio, temperature, and fermentation duration. The maximum enzyme activity recovered was 680 U/g of dry substrate when using $1.38{\times}10^9$ CFU/g as inoculation level, 5.6:1 (ml/g) as moisture ratio (86%), for 4 days of cultivation at $37^{\circ}C$, which was in perfect agreement with the predicted model value. Amylase was purified by Q-Sepharose anion-exchange and Sephacryl S-200 gel filtration chromatography with a 14-fold increase in specific activity. Its molecular mass was estimated at 130 kDa. The enzyme showed maximal activity at pH 5 and $70^{\circ}C$, and efficiently hydrolyzed starch to yield glucose and maltose as end products. The enzyme proved its efficiency for digesting raw cereal below gelatinization temperature and, hence, its potentiality to be used in industrial processes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.283-290
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• 1982

Sardine and mackerel so called dark muscled fish have been underutilized due to the disadvantages in bloody meat color, high content of fat, and postmortem instability of protein. Recent efforts were made to overcome these defects and develope new types of product such as texturized protein concentrates and dark muscle eliminated minced fish. Approach of this study is based on the rapid dehydration of foamed fish-starch paste by dielectric heating. In process comminuted sardine meat was washed more than three times by soaking and decanting in chilled water and finally centrifuged. The meat was ground in a stone mortar added Ivith adequate amounts of salt, foaming agent, and other ingredients for aid to elasticity and foam stability. The ground meat paste was extruded in finger shape and heated in a microwave oven to give foamed, expanded, and porous solid structure by dehydration. Dielectric onstant $(\varepsilon')$ and dielect.ic loss $(\varepsilon")$ values of sardine meat paste were influenced by wavelength and moisture level. Those values at 100 KHz and 15 MHz were ranged 2.25-9.86; 2.22-4,18 for E' and 0.24-19.24; 0.16-1.20 for E", respectively, at the moisture levels of $4.2-13.8\%$. For a formula for fish-starch paste preparation, addition of $20-30\%$ starch (potato starch) to the weight of fish meat, $2-4\%$ salt, and $5-10\%$ soybean protein was adequate to yield 4-5 folds of expansion in volume when heated. Addition of e99 yolk was of benefit to micronize foam size and better crispness. In order to provide better foaming and dehydration, addition of $0.2-0.5\%$sodium bicarbonate, foaming agent, was proper to result in foam size of 0.5-0.7 mm and foam density of $200-400\;/cm^2$ which gave a good crispness. Heating time was depended upon the moisture level of fish-starch paste. For a finger shaped paste (1.0cm. $D\times10cm.L$) heating for 150-200 sec. in a microwave oven (700W. 2.45GHz) was sufficient to generate foams, expand, and solidify the porous structure of fish-starch paste. When the moisture content was above $55\%$ browning and scorching was deepened due to over-expansion and over-heating whereas the crispness was hardened by insufficient expansion at lower moisture content. In quality evaluation of the product, chemical composition of $30\%$ starch and $3\%$ salt added product was moisture $8.8\%$, lipid $2.4\%$, carbohydrate $46.7\%$, protein $36.1\%$, and ash $6.0\%$. Eleven membered panel test evaluated that fish-starch paste was acceptable in color, crisp-ness, taste, except a trace of fishy odour which could be masked by the addition of spice extracts.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.393-397
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• 2004

Rice was steeped at elevated temperatures of $40,\;50,\;or\;60^{\circ}C$ for 2 hr, and physicochemical properties of starches isolated from wet-milled rice flour were investigated. Steeping at elevated temperatures slightly decreased lightness of rice starch, while increased yellowness and redness. Average granule size of rice starch was decreased by steeping treatment. Swelling power and solubility increased as temperature increased. Starch from rice steeped at $40^{\circ}C$ displayed highest swelling power and solubility. Differential scanning calorimetry data of starch obtained from steeped rice at $60^{\circ}C$ showed increased onset and peak temperatures, with narrower gelatinization temperature range, suggesting partial annealing effect. Pasting properties of starch measured by Rapid Visco-Analyzer indicated increased peak viscosity due to rice steeping at $40^{\circ}C$. Peak and breakdown viscosities decreased at $50\;and\;60^{\circ}C$, whereas setback and final viscosities increased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.125-132
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• 1983

Dielectric properties of sardine-starch paste with moisture content of 4 to $13\%$ were investigated as functions of moisture and frequency. And the effects of the levels of fat and starch of the mixtures upon dielectric permittivity, critical moisture, were also mentioned. In addition, a theoretical prediction of frequency dependence of dielectric constant which was computed by the lumped circuit of two layer condenser model was evaluated. For the preparation of sardine-starch paste, comminuted sardine meat was washed thoroughly several times in chilled water by soaking and decanting, and finally centrifuged. This procedure was extended longer to provide a low fat sample. The centrifuged meat was mixed with adequate amounts of starch and salt, and ground for 25 minutes in a stone mortar, moulded in the form of disk with 7cm diameter and 1.2cm thickness and then freeze dried. Dried meat disks were cut off for the size of 5.5cm diameter and 1.0cm thickness and their moisture contents were controlled in humidified desiccators with saturated solutions. Dielectric constants of sardine-starch paste tended to decrease frequency was increased showing a critical charge at the moisture called critical moisture content. In case of the sample with $20\%$ starch and $2\%$ salt an average complex permittivity($\epsilon^{\ast}$) at 7 to $8\%$ morsture as the critical moisture content was presented; $\epsilon^{\ast}$=3.37+j 0.39 at 0.1 MHz, $\epsilon^{\ast}$=2.54+j 0.19 at 15 MHz, and $\epsilon^{\ast}$=2.15+j 0.08 at 1.8 GHz, respectively. The theoretically obtained complex permittivity values from the two layer condoner model were in close agreement with these actual measurements under the same conditions, that appeared as $\epsilon^{\ast}$=2.53+i 0.09 at 0.1 MHz and $\epsilon^{\ast}$=2.28+j 0.06 at 15 MHz, respectively. The fast level of the mixture also revealed an influence on dielectric property that defatted neat with $1.0\%$ fat showed a higher hc and $\epsilon^{\ast}$ value than the meat with $4.8\%$ fat. Complex permittivity being related to the moisture level remained nearly unchanged or slightly changed at the moisture range of 4 to $8\%$ but was dispersed widely at higher moisture contents.

• Food Engineering Progress
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• v.21 no.3
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• pp.280-285
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• 2017

The objective of this study was to increase the efficiency of starch extraction from potato sludge by different concentration of food-grade hemicellulase. The potato sludge, which is a by-product of potato processing industry, was treated with food-grade hemicellulase. Starch extraction efficiency displayed no significant difference in hemicellulase concentration. The purities of potato starch increased from 83.40 to 95.91, 97.44, 95.58, and 97.79%, with treated 0.5, 0.75, 1.0, and 1.5% hemicellulase, respectively. The physicochemical properties of the starches, such as granule structure, particle size, pasting, and thermal transition, were not affected by the concentration of hemicellulase. These results indicate that food-grade hemicellulase treatment is an efficient method for starch extraction from potato sludge.

• Applied Biological Chemistry
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• v.20 no.3
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• pp.292-295
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• 1977

Physicochemical properties of Trichosanthes kirilowii Max. root and starch were investigated. Trichosanthes kirilowii root is made up of 69% of moisture, 2.7% of protein, 0.3% of crude fat, 2.0% ash and 3.4% of crude fiber. Starch granules were in the range of 4.1-22.0 microns in size, the average being 11.0 microns. The starch had raising power of 87.5, amylose content of 26.7% alkali number of 34.3 and blue value of 0.42. The initial and final gelatinization temperature were $60^{\circ}C$ and $67-68^{\circ}C$ respectively.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.2 s.110
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• pp.38-46
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• 2005

Experimental work was carried out in order to produce a novel grade of ink-jet paper that has both high print-out quality and price competitiveness. Usually, silica and PVOH has been used for ink-jet paper to design the coating layer that has a hydrophilic and micro-porous structure. However, poor rheological characteristics and low productivity of the silica-PVOH system make the price of the ink-jet paper high. The main focus of this study was replacing the conventional silica (coating pigment) PVOH (binder) coating system with the new PCC (coating pigment) cationic starch (binder) coating system, and optimizing thecoating technology associated with PPC-cationic starch system. In this study, ink-jet print quality of PCC-coated papers was compared with that of silica-coated paper. Two types of PCC were used: conventional type and colloid type. It turned out that PCC C, a conventional coating pigment, has not given a desirable result: it showed high dot reproduction, but it gave low optical density. In spite of low dot reproduction, the qualities of PCC A were comparable or superior to those of silica in optical density, color reproduction, and the uniformity of printing surface. It was also shown that the problems that are happened when the dosage level of cationic starch was too low were varied with ink-type used in each printer. However, in the case of low binder level, the produced image was widely spread resulting fromtoo low optical density of images, or from the lack of bonding ability to set ink into coating surface.