• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.224-230
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• 1973

The culture used wheat bran as media for four kind of mold strains such as Aspergillus oryzae, Aspergillus kawachii, Aspergillus usamii and Rhizopus javanicus to examine which strain could higher the activity of amylase most which is used for alcohol fermentation. It also provided three different kind of wheat bran media containing starch of 47%, 51% and 55% respectively for each strain. For each media it also added three different kind of nitrogen sources; ammonium sulfate, casein, and ammonium sulfate and casein equally mixed. Each nitrogen source added was subordinately differentiated into three different percentages, 2%, 4% and 6% respectively, except the 2% for the ammonium sulfate. The results obtained were summarized as follows (1) The activity of ${\alpha}-amylase$ was highest in the media of starch value 47% of wheat bran with 6% of casein added. (2) The activity of ${\beta}-amylase$ was highest in the media of starch value 51% of wheat bran with 2% of the equal mixture of ammonium sulfate and casein added. (3) The activities of both ${\alpha}-amylase$ and ${\beta}-amylase$ of Aspergillus usamii were highest in the media of starch value 47% wheat bran with no addition of nitrogen source. (4) Of the four strains examined, the activities of ${\alpha}-amylase$ and ${\beta}-amylase$ cultured in Rhizopus javanicus were both relatively higher. (5) The activities of ${\alpha}-amylase$ and ${\beta}-amylase$ of the strains examined became lower as the percentage of starch contents increased except in Rhizopus javanicus.

• Applied Biological Chemistry
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• v.50 no.3
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• pp.160-166
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• 2007

This study was performed to analyze the molecular structural and physical properties changes of modified rice starch, which particle structure was broken using high impact planetary mill and ultra fine pulverizing techniques. The average diameter and specific surface area of rice starch after pulverization decreased 20% and increased 25%, respectively. Low molecular substances content in rice starch using GPC (gel permeation chromatography) increased from 36.5% to 59.5% after pulverizing of rice starch. Damaged starch contents in rice starch also increased from 16.4% to 99.2% after pulverizing of rice starch. Water holding capacity, solubility and transmittance of rice starch after pulverization increased compared to those of control. Apparent viscosity value of rice starch after pulverization decreased to 7% in control based on $30^{\circ}C$ and 20 RPM conditions.

• Korean journal of food and cookery science
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• v.19 no.1
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• pp.65-71
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• 2003

The objective of this study was to compare the textural properties and sensory evaluation of Injulmi, a traditional Korean waxy rice cake, added with 10, 20 and 30% of RS3-type resistant starch. RS3-type resistant starch was prepared from nonwaxy rice(Odaebyeo) starch by autoclaving-cooling cycle. The RS yield of RS3-type resistant starch was 9.10%. By increasing the addition level of RS3-type resistant starch, the hardness and adhesiveness of Injulmi increased as measured by using a rheometer. Hunter color L and a values of Injulmi added with RS3-type resistant starch were increased, but b value was decreased. In case of sensory evaluation, the hardness of Injulmi added with RS3-type resistant starch was higher than that of non-added Injulmi. The overall duality of Injulmi added with RS3-type resistant starch by sensory evaluation was negatively correlated with the hardness measured by rheometer(p＜.0.05).

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.255-263
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• 1992

Pasting characteristics and amylose-surfactant complex forming ability of sweet potato starch were investigated after defatting and the addition of surfactants, such as SSL (sodium steamyl-2-lactylate) Dimodan (mono/di glyceride) and SE (sucrose ester) with different concentrations. All starch granules were smooth and round, there were no damages to starch granules after defatting and surfactant addition. amylose content of surfactant added stach decreased and me order of decrease was SSL, SE and Dimodan. The cornplex forming ability of SE added starch increased according to increasing HLB value. As surfactants concentration increased, amylose complex formig ability increased. In case of gelatinization patterns by amylograph, the initial pasting temperature of surfactant added starches was higher than mat of untreated or defatted starches, but viscosity at each temperature were all decreased. Soluble carbohydrate and leached amylose of starches increased at increasing temperature, those of surfactant added starches decreased at each temperature in the order of SSL, SE and Dimodan.

• Applied Biological Chemistry
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• v.28 no.4
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• pp.239-244
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• 1985

Physicochcmical properties of the Lotus root starch wert investigated. The shape of starch granules was elliptical with the average size of $20{\sim}35{\mu}$. Starch showed B-type X-ray pattern. The content of amylose was 22.1%. The blue value for starch and amylose were 0.280 and 0.692, respectively. The alkali number was 4.74. By X-ray diffraction examination, gelatinization began at $55^{\circ}C{\sim}60^{\circ}C$ and almost completed at $65^{\circ}C{\sim}70^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.123-129
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• 1993

Physico-chemical properties of the acetylated and raw starch were Investigated with the chucheongbyeo and samkangbyeo. The solubility and swelling power was increased by acylation reaction. The light transmittance was higher in the acetylated rice starch. The blue value of chucheongbyeo and samkangbyeo rice starches were lowered to 10.9% and 16.0%, respectively, by the acylation reaction. The alkali number was 7.6 in the chucheongbyeo rice starch and 7.2 in the samkangbyeo rice starch, whereas acylated starch in the same orders was 55 and 52, respectively. The hardness, adhesion, cohesion of starch gel was increased by the acylation reaction. The temperature of initial gelatinization of the acetylated chucheongbyeo and samkangbyeo rice starch was shown to $59^{\circ}C\;and\;62^{\circ}C$, respectively, lowering $5{\sim}6^{\circ}C$ in temperature by the acylation. The viscosity as well as by the acylation reaction was raised 38% and 14%, respectively. The rice starch particles were shown to plygonal structure. But it were deformed in the acylated starch, and was completely destroyed in the starch which is by gelatinized for 30 min. at $70^{\circ}C$.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.1
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• pp.25-29
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• 1975

The weekly change of sugar and starch content in unfilled grain of Jinheung (temperate rice var.) and IR667-Suweon 214 (tropical rice var.) and of filled grain ratio (less than specific gravity 1.06 for Jinheung and 1.03 for IR667), filled grain weight and unfilled grain weight from flowering and the relationship among them were as fallows. 1. Total sugar content in unfilled grain was twice in Jinheung than in IR667 and starch content was higher (about 2.5 to 3.5%) in Jinheung but starch/sugar ratio was greater in IR667. Thus IR667 that was classified as high sugar type in leaf sheath and internode appears to be high starch type in sink (grain). 2. Under the favorable condition the weight of unfilled grain reached to minimum value and followed by maximum filled grain ratio and lastly by maximum weight of filled grains per ear. 3. Sugar and starch content gradually increased and then decreased during ripening and the maximum values reached prior to maximum filled grain ratio (6 weeks). Sugar content reached to maximum much earlier than starch content did and increased again from 8 weeks later. 4. Starch/sugar ratio reached to maximum value earlier than maximum starch content and earlier in IR667 than in Jinheung. 5. Maximum starch content of unfilled grain in Jinheung was 51.1%.

• Food Engineering Progress
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• v.15 no.4
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• pp.382-387
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• 2011

Physicohemical properties of dual-modified rice starches, cross-linked (with $POCl_{3}$) and hydroxypropylated (with propylene oxide) rice starches, were studied. Rice starch was cross-linked using $POCl_{3}$ (0.005%, 0.02% (v/w)) at 45$^{\circ}C$ for 2 hr and then hydroxypropylated using propylene oxide (2%, 6%, 12% (v/w)) at 45$^{\circ}C$ for 24 hr, respectively. Swelling power, solubility, thermal properties (DSC) and pasting properties (RVA) of cross-linked and hydroxypropylated (CLHP) rice starches were determined. Swelling power of CLHP rice starch increased at relatively lower temperature than native rice starch. Solubility of CLHP rice starch was lower than that of native rice starch. Peak viscosity of CLHP rice starch was lower than that of native starch while holding strength and final viscosity were increased with modification. Breakdown value was lower and setback value was higher than native rice starch. DSC thermal transitions of CLHP rice starch shifted toward lower temperature. Amylopectin-melting enthalpy of CLHP rice starch decreased, whereas it was not affected by the amount of $POCl_{3}$.

• Food Science and Preservation
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• v.20 no.3
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• pp.372-378
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• 2013

The objective of this study was to evaluate the quality characteristics of mungbean starch gels that were prepared with different concentrations (0, 0.5, 1.0 and 1.5%) of peach seed powders (PSP), which exhibit antioxidant characteristics. Mungbean starch gel samples were prepared and subjected to quality characteristics such as moisture content, general components, color, texture profile analysis, total polyphenol contents, DPPH radical scavenging activity, and sensory qualities. The L-value and the a-value for color decreased significantly, whereas the b-value increased significantly as the PSP concentration increased (p<0.05). In the texture profile analysis, the mungbean starch gel with 1.5% PSP showed significantly lower degrees of hardness, cohesiveness, springiness, gumminess and brittleness (p<0.05). The total polyphenol content was highest in the 1.5% PSP to which mungbean starch gel was added, which also showed a higher than 70% DPPH radical scavenging activity level in a dose-dependent manner (p<0.05). In the sensory test of the mungbean starch gel, its sensory scores for flavor and taste were highest in the 0.5% PSP to which mungbean starch gel was added.

• Korean Journal of Food Science and Technology
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• v.4 no.2
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• pp.77-83
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• 1972

In order to study the processing adaptability of naked barley, SEDOHADAKA variety produced in Cheolanam-do(1971) was milled after polishing and examined with respect to its proximate principles, amino acid composition, viscosity, raising power, and amylose content, alkali number, blue value and X-ray diffraction pattern of its starch. The results are summarized as fllows: 1) Crude fiber content of naked barley which was milled at 81.6% (A), 79.2% (B) and 74.1% (C) was $2.48{\sim}2.36%$, indicating higher level than wheat flour. 2) Whereas the initial gelatinization temperature of naked barley flour was similar to that of wheat flour, the value of naked barley starch was $89.5^{\circ}C$, higher than that of wheat starch, Amylose content of naked barley starch was 28.5%, similar to wheat starch. 3) Raising power of naked barley starch was generally lower than that common cereal starches. 4) According to the X-ray diffraction pattern diagram, the degree of crystallization was lower in naked barley starch than in non-glutinous rice starch.