• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.573-579
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• 2010

This study investigated starch properties of 'Daehak waxy corn (DWC)' with different harvest times. The DWCs were harvested at 4 days before suitable time (BST), suitable time (ST) and 4 days after suitable time (AST). As harvest time was delayed, starch yield and amylopectin content of DWC starch increased from 43.21 to 52.73%, and from 90.79 to 92.83% based on dry weight, respectively. As harvest time was postponed, enzymatic digestibility and water solubility of DWC starch decreased from 81.43 to 80.58%, and from 10.23 to 9.23%. However, water binding capacity and swelling power of DWC starch increased from 227.94 to 244.88%, and from 24.75 to 29.74%, respectively. Retrogradation viscosity of starch was the lowest in DWC harvested at AST. There was a high correlation coefficient among starch properties of DWC, such as starch yield, enzymatic digestibility, water binding capacity, swelling power, water solubility and retrogradation viscosity (p<0.01). As harvest time was deferred, enzymatic digestibility, water solubility and retrogradation viscosity decreased; however, amylopectin content increased, and water binding capacity and swelling power significantly increased with increasing amylopectin content.

• 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 $POCl_{3}$.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.1119-1126
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• 2017

Quality characteristics of commercially available soybean and mung-bean flours in Korea were evaluated relative to product information such as bean content, price, chromaticity, proximate composition, water binding capacity, swelling power and solubility. Origin of raw materials was 23 in domestic products and 19 in imported products. The price of the product was 3.48 times more for raw soybean flour, 3.34 times more for fried soybean flour, and 3.47 times more for mung bean flour compared to imported soybean. In the domestic products, the lightness of raw soybean flour was higher than roasted soybean flour. The redness and yellowness of roasted soybean flour were higher than raw soybean flour. Moisture content of raw soybean flour was higher than roasted soybean flour, and crude fat, crude protein and carbohydrate content were higher in imported soybean flour. Ash and crude protein contents of mung bean were slightly higher than imported products. Water binding capacity of roasted soybean flour in domestic products was higher than raw soy flour, and there was no significant difference in solubility and swelling power. Correlation between quality characteristics of commercially available soybean and mung-bean flours products was found to be highly significant among measured items, except for solubility.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.855-860
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• 2009

Physicochemical properties of starches isolated from 3 new potato cultivars developed by Potato Valley Ltd. were investigated and compared to those of starch isolated from 'Superior' being distributed prominently in Korea. Significant differences were observed in physicochemical properties such as granule size, amylose content, phosphorus content, water binding capacity, swelling power, solubility, and in vitro digestibility of starches from different potato cultivars. Thermal properties were evaluated using differential scanning calorimetry (DSC), and onset gelatinization temperatire ($T_o$), peak temperature ($T_p$), and enthalpies of gelatinization (${\triangle}H$) of different potato cultivars ranged as $58.0{\pm}0.3-61.7{\pm}0.4^{\circ}C,\;63.7{\pm}0.2-$ $66.5{\pm}0.0^{\circ}C$, and $15.6{\pm}0.5-17.0{\pm}0.3$ J/g, respectively. Pasting properties were evaluated using a rapid visco analyzer (RVA), and pasting temperature, peak viscosity, and final viscosity of different potato cultivars ranged as $65.0{\pm}0.1-68.9{\pm}0.1^{\circ}C$, $8,163.7{\pm}196.3-9,035.7{\pm}6.4$ cp, and $4,397.7{\pm}166.7-7,025.0{\pm}271.3$ cp, respectively. Especially, 'Gogu valley' starch showed the highest values in the amylose and phosphorus content among tested potato cultivars and higher water binding capacity, swelling power, and solubility than those of other tested starches. And it also showed high pasting temperature, peak viscosity, trough viscosity, and final viscosity as compared to other tested starches.

• Korean journal of food and cookery science
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• v.16 no.1
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• pp.22-26
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• 2000

In order to economically utilize dough with B. infantis and S. thermophilus as a bread improver, WHC, swelling power, solubility, farinograph, extensograph and amylograph of dough were investigated. Swelling power and solubility were less than medium flour and weak flour. WHC was higher than those. On rheological properties of dough, farinograms of dough showed progressively increasing water absorption, peak time only increased with addition of S. thermophilus. Extensograms showed that area increased S. thermophilus and B. infantis at 135 min. Extensibility and resistance to exntension of dough were higher in S. thermophilus than those in B. infantis. On amylograms, maximum viscosity of dough increased by addition of B. infantis and S. thermophilus.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.585-591
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• 1997

The proximate composition and physicochemical properties of three cultivars of Korean kidney bean sediments, Pink (PKB), Red (RKD) and White (WKB) were compared. No significant differences in the proximate composition and calorie were noticed among three samples. Sediment granule was oval/round and rough in all samples. The amylograms showed no peak and continuous increase of viscosity during heating. The water-binding capacities of the sediments were 322.4∼355.0%. The swelling power and solubility were 5.93∼6.68% and 3.76∼5.28%, respectively. The percent transmittances of the sediment suspension decreased linearly from 50$^{\circ}$∼75$^{\circ}C$. The gelatinization temperature and gelatinization enthalpy determined by DSC (Differential Scanning Caloriemeter) were much lower than those of starches.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.461-467
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• 1993

The purpose of this study was to investigate the physico-chemical properties of potato starch heated with microwave. Two types of potato starches are prepared; in group A raw potato starch was heated with microwave and in group B potato starch was isolated from potato heated with microwave. Both groups were exposed to the microwave energy in a 560 W, 2,450 MHz oven for 60, 120, 180 and 300 seconds. As the microwave heating time took longer, free lipid decreased and bound lipid increased in both groups. The shape of starch granules, birefrigence and X-ray diffraction pattern were not changed much by microwave heating in both groups. Water binding capacity increased, but amylose content, swelling power and solubility decreased as the microwave heating time took longer. It was also found that the extent of decreases in swelling power and solubility were different between group A and group B.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.1-7
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• 1990

Starch samples of rice and glutinous rice starches were adjusted to 27 % of moisture and heated at $100^{\circ}C$ for 16 hours, respectively. After the treatment, their physicochemical properties were investigated. The granule shapes of all the starches were polygonal and they became slightly bigger in their sizes after the treatment. All their X-ray diffraction patterns were A types. The specific gravity of the starches decreased to 1.03-1.09 by the treatment. The water binding capacity of rice starches increased, while that of glutinous counterparts slightly decreased. Almost no change in the amount of amylose included was found. Swelling power and solubility were increased with the increase of temperature. At a certain temperature, however, the solubility of the treated starches increased when the swelling power decreased. The initial gelatinization temperatures of Akkibare, Yongmun, and Taebaek starches were $60{\sim}65^{\circ}C$ but those of glutinous rice starch and U.S.A. rice starch were $55{\sim}60^{\circ}C$ and $70{\sim}75^{\circ}C$, respectively, as measured by transmittance. The gelatinization temperature of the treated starches was higher than that of the untreated starches.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.720-729
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• 1996

Effect of the cellulase treatment on the physicochemical properties of three varieties of rice (chucheongbyeo, chosengtongilbyeo and IR 36) and the texture of cooked rice were investigated. The swelling power and solubility of the rice flours were increased and amylographic viscosities, especially cold viscosities were decreased by cellulase treatment in all varieties. Gel chromatography of soluble carbohydrates from cellulase-treated rice flours on sepharose 2B-CL showed a singificant increase of low molecular weight $(10^{4})$ fraction which might be produced upon hydrolysis in endosperm cell wall constituents. The hardness of cooked rices prepared from cellulose-treated rices significantly decreased.

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.334-339
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• 1993

Physicochemical properties such as amylose content, swelling power, gelatinization and DSC of legume starches were investigated. The granule shape of legume starches was oval. The size of cowpea and mung bean were smaller than kidney bean and red bean. The amylose content of mung bean and kidney bean was larger and were $25{\sim}29%$. Swelling power of kidney bean starch was much lower than other starches in all temperature range. In gelatinization temperature by Brabender amylogram, red bean starch was low, but kidney bean starch was rather high. Amylographic hot-paste viscosity and set back of cow pea, mung bean and red bean starches were high. But those of kidney bean starch were very low. DSC results Indicated kidney bean starch gelatinized in higher temperature. From above results, row pea and mung bean starches were similar in granule size and shape, solubility and swelling power, amylogram, and DSC thermogram. But kidney bean starch was very different and red bean starch was slightly different with the physicochemical properties of cow pea and mung bean starches.