• Food Science and Biotechnology
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• v.17 no.1
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• pp.176-179
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• 2008

Amylose contents and amylopectin chain architecture of sorghmn and waxy sorghum starches were determined and compared with those of other common cereal and tuber starches. Also, in vitro digestibility of sorghum starch was estimated using a novel methodology. The absolute amylose content of sorghum starch was similar to that of com and wheat starches. The side chain length distribution patterns for sorghum and waxy sorghum amylopectin were very similar to those of com and waxy com, respectively. The $k_{cat}/K_m$ values for sorghum and potato amylopectin did not show a significant difference. The kinetic parameters could be used as novel indicators for starch digestibility.

• 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 and cookery science
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• v.21 no.5
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• pp.677-684
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• 2005

This study investigated the changes in physicochemical characteristics after 120 days of aging Korean red pepper paste, 'Kochujang', made of minor cereals in substitution for glutinous rice which has been conventionally used as starch source. The cereals used were waxy job's tears, proso millet, sorghum, barley and foxtail millet, Glutinous rice with barley was used as controls. The items determined were water activity, pH, content of amino nitrogen, chromaticity and sensory test. 1. The water activities(Aw) of Kochujang samples were in range of $0.72{\sim}0.82$ at the beginning of fermentation, with Aw barley paste bing the lowest, and Aw of sorghum paste bing the highest. Then Aw were slowly decreased to the range of $0.49{\sim}0.50$ during 120 days of fermentation 2. The pH of the pastes was in range of $4.94{\sim}5.02$ at the initial time of fermentation, and decreased steadily to 4.32{\sim}4.73 at the end. 3. The content of amino nitrogen was in range of $330.9{\sim}340.7\;mg%$ at the early time of fermentation. The highest content, $351{\sim}381\;mg%$, was observed at the 90th day of aging of glutinous rice paste, 105th day of job's tears paste, 75th day each of barley and proso millet, and 60th day each of sorghum and foxtail millet. 4. The Hunter tristimulus values (L, a, b) of all pastes were gradually decreased during fermentation. The value of barley paste was lowest among the pastes. 5. The texture of barley paste in sensory test showed significant difference with other pastes, whereas there were no differences in color, odor, taste and sensory qualities.