• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1086-1090
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• 1997

Morphological properties on lintnerized maize starches with different amylose content were investigated. With increasing the lintnerization periods and decreasing the amylose content, hydrolysis rate was increased. As amylose content of starch was increased, the degree of damage with acid treatment was decreased by SEM. With increasing hydrolysis, iodine affinity, apparent amylose content and ${\lambda}_{max}$ of lintnerized starches were decreased. Water binding capacities of lintnerized starches were higher than those of native starches.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.379-383
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• 1997

To study the effect of amylose on the mechanism of gel formation, swelling power, water solubility, the pattern of alkali gelatinization and gel properties were investigated. The swelling power of waxy maize starch (Amioca) was the highest and followed by those of PFP > Amaizo > Amylomaize VII. Amioca showed higher iodine affinity of soluble amylose than other maize starches. The apparent viscosity of alkali gelatinization measured by Brookfield viscometer for Amaizo was 70${\times}$10$^3$cp which was higher than Amylomaize VII. The apparent viscosity of PFP was increased to 70${\times}$10$^3$cp and then decreased. As maize starches were autoclaved at 121$^{\circ}C$ with starch: water ratio (1 : 9) and autoclaving-cooling cycle were up to 4 times, gel properties were measured by rheometer. Amaizo showed the highest value for hardness, adhesiveness, springiness, and cohesiveness, and hardness of gel after two cycles of autoclaving-cooling was the highest. Gel properties seemed to be affected by the chain length of amylose rather than the content of amylose.

• Food Engineering Progress
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• v.21 no.4
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• pp.341-350
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• 2017

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

• Proceedings of the SOHE Conference
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• 1997.12a
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• pp.45-49
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• 1997

To study the effect of amylose on the mechanism of gel formation, swelling power, water solubility, the pattern of alkali gelatinization and gel properties were investigated. The swelling power of waxy maize starch(Amioca) was the highest and followed by those of PFP ＞Amaizo ＞ Amylomaize Ⅶ. Amioca showed higher iodine affinity of soluble amylose than other maize starches. The apparent viscosity of alkali gelatinization measured by Brookfield viscometer for Amaizo was $70{\pm}10^3cp$ which was higher than Amylomaize VII. The apparent viscosity of PFP was increased to $70{\pm}10^3cp$ and then decreased. As maize starches were autoclaved at $121^{\circ}C$ with starch : water ratio (1:9) and autoclaving-cooling cycle were up to 4 times, gel properties were measured by rheometer. Amaizo showed the highest value for hardness, adhesiveness, springiness, cohesiveness, and hardness of gel after two times of autoclaving-cooling cycles was the highest. Gel properties was thus affected by the chain length of amylose rather than amylose content.

• 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 and cookery science
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• v.13 no.4
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• pp.478-483
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• 1997

The effects of defatting by ether or 85% methanol on the properties of nonwaxy rice flours (Odaebyeo and Mankeumbyeo) were investigated. Starch granules in the rice flour were all polygonal and showed all A-type crystalline patterns regardless of defatting. Amylose content of the rice flour extracted by ether (crude lipid-defatted rice flour, CLDRF) was similar to the untreated (untreated rice flour, URF), however, that of 85% methanol (total lipid-defatted rice flour, TLDRF) was increased. Defatting decreased the water binding capacities of rice flour in all samples. The swelling power of rice flour was higher in Odaebyeo than Mankeumbyeo, and that of CLDRF showed a similar pattern to the untreated. Swelling power was the highest in TLDRF up to 85$^{\circ}C$, but decreased in the following order CLDRF > URF > TLDRF at above 95$^{\circ}C$. A similar pattern was observed in the leached soluble fraction, and its apparent amyloae content was increased rapidly at above 85$^{\circ}C$.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.871-881
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• 2012

To compare the physicochemical and gel properties of mung bean starches prepared by different purification methods, starches from Korean Eohul variety and Chinese mung bean (MB) with or without hull using alkaline solution or water as solvent were purified. The optimum conditions for making muk were investigated. Apparent amylose and total dietary fiber contents, water binding capacity, solubility and pasting properties by RVA were analyzed. The characteristics of starch gels (10% dry basis) were measured for 0 and 4 day stored at $4^{\circ}C$. The protein and ash contents were significantly different (p<0.05) and lowered in starch from dehulled MB using alkaline solution. The starches from dehulled MB using alkaline solution showed the lowest color differences. Apparent amylose contents of Eohul and Chinese starches showed 37.06-39.03% and 31.57-32.74%, respectively. Chinese starch was higher in water binding capacity but lower in solubility at $85^{\circ}C$ than others. Peak, trough, cold, and breakdown viscosities of Eohul starch were higher than those of Chinese one. Mung bean starch gel made immediately exhibited clear and glossy appearance but became whiter like milk. The crystallinities of starch and starch gel showed A and B types, respectively. The hardness, gumminess, and resilience of starch gel made immediately and hardness, cohesiveness, gumminess, and resilience of 4 day stored gels were different significantly (p<0.05). Especially, Eohul starch gels purified from hulled MB showed higher resilience (bending property) and hardness. Therefore, it was suggested that high quality muk would be made using MB starch purified from hulled Korean mung bean using water as solvent.decreased in contain more than 20% of SGP added groups. The optimal concentration of SGP was found in the range of less than 10%.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.339-347
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• 2011

Flour and isolated starch from chickpea (desi type, 328S-8) were evaluated for their in vitro digestibility and physicochemical properties. The protein content, total starch content and apparent amylose content of chickpea flour and isolated starch were 22.2% and 0.6%, 45.8% and 91.5%, and 11.7% and 35.4%, respectively. Chickpea starch granules had an oval to round shape with a smooth surface. The X-ray diffraction pattern of chickpea starch was of the C-type and relative crystallinity was 24.6%. Chickpea starch had only a single endothermic transition (13.3 J/g) in the DSC thermogram, whereas chickpea flour showed two separate endothermic transitions corresponding to starch gelatinization (5.1 J/g) and disruption of the amylose-lipid complex (0.7 J/g). The chickpea flour had a significantly lower pasting viscosity without breakdown due to low starch content and interference of other components. The chickpea starch exhibited significant high setback in the viscogram. The average branch chain length, proportion of short branch chain (DP 6~12), and long branch chains (DP${\geq}$37) of isolated chickpea starch were 20.1, 20.9% and 9.2%, respectively. The rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) contents of chickpea flour and starch were 9.9% and 21.5%, 28.7% and 57.7%, and 7.1% and 9.3%, respectively. The expected glycemic index (eGI) of chickpea flour (39.5), based on the hydrolysis index, was substantially lower than that of isolated chickpea starch (69.2).

• Korean journal of food and cookery science
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• v.31 no.3
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• pp.248-254
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• 2015

We conducted this study to investigate the amount of RS and cooking characteristics of the commercial extrusion-cooked noodles. Ten kinds of noodles were selected and grouped according to the storage conditions; dry noodles (3), refrigerated noodles (2), freeze noodles (4), and dry noodle made from wheat flour as a control (not extrusion-cooked). The total starch of commercial noodles ranged from 62.50% to 84.13%, Refrigerated Naengmyeon and dry Dangmyun had high proportions of total starch (respectively 84.13% and 80.13%, respectively). The amounts of apparent amylose ranged from 25.01% to 42.93% and RS ranged from 0.61% to 5.99%. A high proportion of the total starch was rendered digestible by extrusion cooking, and a small amount of RS remained in the samples. Dry Dangmyun had the highest percentages of RS (5.99%), followed by refrigerated Naengmyeon C (2.41%) and dry Jjolmyeon (1.94%), and those of the other noodles were lower than that of the control (1.86%). Cooking properties and texture measurements were evaluated. Cooking loss and turbidity of cooking water were highest in dry Jjolmyeon and dry Naengmyeon. There was little cooking loss in dry Dangmyun and freeze rice noodles. In particular, dry Dangmyun and refrigerated Naengmyeon C containing high amounts of RS and amylose had relatively high measurements of hardness and tensile strength.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.403-407
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• 1995

For the use of starch gel like Mook(a Korean traditional gel food), the physicochemical properties and gelatinization patterns of defatted high amylose corn starch were investigated. The crude and total lipid contents of starch decreased by defatting from 0.07%, 0.92% to 0.03%, 0.19%, respectively. But iodine affinity increased from 51.6% to 71.3%. Water binding capacity of starches increased from 104.6% to 117.3% after defatting. Soluble carbohydrate and leached amylose of untreated and defatted starches were increased rapidly above $110^{\circ}C$. The apparent viscosity of starch dispersion using alkali solution increased above 0.3N NaOH solution but the transmittance increased above 0.4 N NaOH. The DSC thermograms of both starches showed broad and double endotherm with relatively low enthalpy, but the second peak of endotherm was larger in defatted starch than in untreated starch.