• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.528-535
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• 1989

Starches isolated from Seipoong and Daeji potato were classified into small and large granules. The starch granule size for Seipoong and Daeji was in the range of $10-85\;{\mu}m$ and $13-90\;{\mu}m$, respectively. Seipoong starch contained more large granules $(>41\;{\mu}m)$ while Daeji starch had more small granules $(<30\;{\mu}m)$. There was no difference in water-binding capacity both between two starches and among granule sizes. Amylose content for toro starches was the same but was higher in large starch granules than small ones. Swelling powder at $80^{\circ}C$ for parent starches was essentially the same but small starch granules had much higher swelling powder than large ones. The large starch granules for Daeji showed higher peak viscosity by amylograph than small starch granules. No such difference was observed for Seipoong starch. The gelatinization temperature range of small starch granules was wider than that of large ones, but gelatinization enthalpy was the same between large and small starch granules. The starches regardless granule sizes were completely gelatinized at $70^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.766-771
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• 1989

physicochemical properties of rice starch isolated from eight varieties were examined to evaluate the rice processing suitability The amylose contents of rice starch were varied with 16.7-29.7%, and IR 30, Godael, Aguja and Lengkwang varieties showed higher amylose content than the other varieties. The water binding capacity and blue value were in the range of 87.0 103.0 and 0.178-0.305, respectively. As the amylose content increased, the amylogram pasting temperature and the break down ratio increased, while the peak viscosity did not show any significant difference. The transmittance of 0.1% starch suspension slowly increased at $50^{\circ}C$ in the low-amylose content rice group, and rapidly increased at $65^{\circ}C$ in the high-amylose content rice group, but there were no differences above $75^{\circ}C$ among varieties. Also the low-amylose rice starch showed higher values in the swelling power and solubility. The hardness of the 30% rice starch gels was low in low-amylose one. During storage at $20^{\circ}C$ for 14 days, the increment of hardness was more slow in high-amylose one. The retrogradation velocity constant of rice starch gel by Avrami equation was the highest as 0.219 in Aguja variety.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.753-761
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• 1990

The physicochemical properties of starches from aerial and subterranean tuber of yam were compared with those of rice and sweet potato. Aerial tuber yam contained higher level of amylose than others, whereas water binding capacity, swelling power and solubility was highest in subterranean tuber yam starch. Brabender amylograms of 5% starch suspensions indicated that the initial pasting temperature of yam starches were slightly higher than that of rice and sweet potato starches, the maximum viscosities of starches from subterranean and aerial tuber yam were 860 and 590 B.U., respectively. Yam starches were more difficult to hydrolyze by ${\alpha}-amylase$ than rice and sweet potato starches. ${\beta}-Amylolysis\;limit$ for yam starches and their amylose and amylopectin were higher than rice and sweet potato starches. The elution profiles of starches on Sepharose CL-2B were different from each other but they were similar between yam starches. Incomplete debranched fractions in the aerial tuber yam amylopectin was particularly higher than other samples. The weight ratio of short chains to long chains for debranched amylopectins was the lowest in aerial tuber yam.

• Korean journal of food and cookery science
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• v.6 no.3 s.12
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• pp.1-7
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• 1990

The physicochemical properties of acorn and chestnut starches were investigated. The shape of two starches granules was the rounded trianglar and some elliptical, but that of chestnut was less rounded. Water binding capacity of acorn was 191% and that of chestnut was 200%. Gel volume of chestnut started to increase from $55^{\circ}C$, and was higher value in all temperature range. Amylose of chestnut starch was leached more than that of acorn to $90^{\circ}C$. and reversely from $90^{\circ}C$ to $100^{\circ}C$. The blue value and amylose content of acorn and chestnut starches were 0.464, 0.440 and 24.8%, 22.5 respectively. According to Brabender Amylogram, gelatinization temperature and peak. hot and cold viscosity were $68.5^{\circ}C$, 1010, 910, 1470 BU for acorn and $63.7^{\circ}C$, 1480, 1000, 1080 BU for chestnut. Peak temperature and gelatinization enthalpy were $67.0^{\circ}C$ 3.64 cal/g for acorn, and $66.0^{\circ}C$, 2.82 ca1/g for chestnut. X-ray diffraction patterns of two starches were A-types but chestnut had some B-type character.

• Korean journal of food and cookery science
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• v.29 no.2
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• pp.129-135
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• 2013

The objective of this research was to investigate physicochemical properties of waxy sorghum flours by different milling methods (pin mill and ultra fine mill). Four different sorghum flours were used for the experiments ; PWS (pin milled whole sorghum flour), PS (pin milled sorghum flour without bran), UFWS (ultra fine milled whole sorghum flour), UFS (ultra fine milled sorghum flour without bran). The contents of crude ash and total dietary fiber were the highest in PWS. Amylose content of pin milled sorghum flour was higher than that of ultra fine milled flour. The mean particle size of pin milled flours was six times lager than ultra fine milled flours. The L values of UFS and UFWS were higher than those of PS and PWS, whereas a and b values were higher in PWS. The water binding capacity was highest in UFWS, and solubility was higher in PS and UFS. Swelling power of flours was highest in UFS. The damaged starch content was higher in PS and UFS, which means damaged starch of sorghum flours significantly affected by polishing than milling method. The pasting properties were higher in the pin milled flours. Initial pasting temperature of pin milled flour was ranging from 70.5 to $73.1^{\circ}C$, which are higher than ultra fine milled flour ($68.6^{\circ}C$). The contents of total polyphenol were higher in PWS and UFWS than those of PS and UFS, there was no difference between the two milling methods. The results of this study indicate that physicochemical properties of sorghum flour were affected by milling methods as well as bran.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.306-312
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• 1995

In order to know properties in rice starch during storage of rice, rice starch from stored rice(stored at $5^{\circ}C$, R.H. 65% and $30^{\circ}C$, R.H. 85%, for 16 weeks) used in this experiment. Water binding capacity of rice starch increased for 8 weeks, and then it decreased. As the storage period took longer, swelling power and solubility, optical transmittance, blue value, total amylose content and soluble amylose content decreased. For the same periods, changes in rice starch from stored rice$(30^{\circ}C$, R.H. 85%) were made more than those in rice starch at $5^{\circ}C$, R.H. 65%. The granule shape of rice starch, irrespective of storage periods and conditions, didn't make a significant difference. The relative crystallinity of the rice starch by X-ray diffraction didn't distinctly changed till the second week. But, at the fourth week, that by X-ray diffraction significantly decreased, and then slightly decreased. As the storage period took longer, gelatinization temperature, melting temperature and melting enthalpy measured by DSC got higher, but gelatinization enthalpy got lower. For the same storage period, gelatinization temperature, melting temperature, gelatinization enthalpy and melting enthalpy of rice starch stored at $30^{\circ}C$, R.H. 85% made changes more than those of rice starch stored at $5^{\circ}C$, R.H. 65% did.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1300-1306
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• 2011

This study investigated the physicochemical characteristics of wet-milled rice flour treated with pectinase and cellulase in a steeping process. Enzyme treatments were used as follows: pectinase 0.05%, cellulase 0.05%, and mixed enzyme treatments 0.05~0.2%. For particle distribution, rice flour E-treated with mixed enzymes (pectinase 0.05% and cellulase 0.05%) was the finest at 48.3% particle distribution less than $53\;{\mu}m$. Protein contents and damaged starch were reduced by enzyme treatments. Damaged starch was the lowest (12.1%) in rice flour E compared with non-enzyme treatment (18.1%). Amylose content, water binding capacity, solubility, and swelling power all increased upon enzyme treatments, and their effects increased upon mixed enzyme treatment. For gelatinization characteristics of RVA, peak viscosity, final viscosity, breakdown, and total setback viscosity increased in rice flours treated with mixed enzymes. Especially, in steeping method with mixed enzyme treatment, pectinase 0.05% and cellulase 0.05% treatment was suitable for minimizing damaged starch and high fine particle distribution of rice flours compared with single enzyme treatment.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.3
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• pp.353-360
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• 2008

This study evaluated the quality characteristics of dried noodles made of wheat flour supplemented with different concentrations of skate powder. Cooking quality, mechanical texture properties, gelatinization temperature and viscosity were measured, after which sensory evaluation was performed with prepared noodles. Water binding capacity, solubility and swelling power of the composite skate powder and wheat flours were higher than those of pure wheat flour. Gelatinization temperature of the composite skate powder and wheat flours increased, while initial, interim, and maximum-viscosity at $95^{\circ}C$, decreased, with increasing skate powder content. In relation to color values, increasing skate flour content led to decrease in L and b values and increase in a value. For the textural characteristics, the addition of skate powder increased hardness, springiness, chewiness and adhesiveness. Overall, noodles made with 3% skate powder were preferred compared to other samples.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.16-20
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• 2009

To develop health functional foods using high amylose rice flours, the properties of flours prepared from domestic high amylose rice varieties, Goamy2 and Goamy, and imported rice from Thailand were investigated. After soaking the rice grains and drying, the dry-milled rice flours were passed through a 120-mesh sieve. The protein and total starch contents of the Goamy2 rice flour were lowest, but its crude lipid and ash contents were highest among the flours. In addition, apparent amylose content, water binding capacity, and total dietary fiber were highest in the Goamy2 flour (36.2, 255.0, and 9.2%, respectively). The Thai rice flour had the highest swelling power, whereas the Goamy2 flour had the lowest swelling power and solubility. By Rapid visco-analysis, the Thai flour showed the highest peak and total setback viscosities and lowest breakdown viscosity. The pasting pattern of the Goamy2 flour was different from that of the other flour, where low viscosity was maintained during heating and cooling. Goamy and Thai rice flours showed an A type crystallinity, but Goamy2 flour showed a B type crystallinity similar to high amylose maize starch. The Goamy2 flour presented a dull and yellowish color, and the lowest lightness (L) value and the highest yellowness (+b) value.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.714-720
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• 2010

This study was carried out to investigate the effects of Hericium erinaceum (HE) powder and extract on the quality characteristics of noodles. The water binding capacity of the HE powder was higher than that of pure wheat flour. Gelatinization temperature of HE powder-wheat flours gradually were increased and initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 min and maximum viscosity of those composites were decreased, as measured by a amylograph. The noodles showed decreased L values and increased a and b values with increasing HE powder in the wheat flour composite. The mechanical properties of the control cooked noodles showed the highest hardness, which decreased with the addition of HE powder. Springiness, cohesiveness, and gumminess decreased with increasing amounts of added HE powder. While the higher adhesiveness of noodles increased with more preferred than the control, and considerably the greatest overall acceptability of noodles was for those containing 2% HE powder.