• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.201-205
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• 1984

Some physicochemical properties of ginger root (Zingiber officinale) starch were compared with those of cross-linked corn starch. The ginger root starch that contained 23.5% amylose had a water-binding capacity of 99.1% and a B-type X-ray diffraction pattern. The optical transmittance of the ginger root starch suspension increased from $70^{\circ}C$ and showed a similar pattern to cross-linked corn starch. Solubility studies revealed that both ginger root and cross-linked corn starches had low swelling power and solubility in water up to $90^{\circ}C$, and reduced solubility in potassium hydroxide. Brabender amylograph data indicated that the ginger root starch (7%) had a relatively high initial pasting temperature $(81.5^{\circ}C)$ and was stable against heat and mechanical shear, which resembled to the cross-linked corn starch.

• 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.

• Applied Biological Chemistry
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• v.27 no.3
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• pp.198-203
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• 1984

Ethanol fermentation of chemically gelatinized starch and uncooked raw starch was nested with various starchy materials. Starches were gelatinized by 5.4% NaOH and neutralized by sulfuric acid. The patterns of $CO_2$ evolving and the ethanol yield for the chemically gelatinized starch resemble those obtained with thermally gelatinized starch. The alcoholic fermentation of raw starch was carried out by the simultanous saccharification-fermentation using a commercial glucoamylase and yeast. Ethanol yield from uncooked rice starch fermentation was highly comparable to that from cooked one. $CO_2$ evolving rates of the uncooked starches of corn, barley, tapioca and sweet potato were lower than those of the cooked starches. However, the final ethanol yields were similar or slightly lower, depending on the types of starch.

• 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.

• Applied Biological Chemistry
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• v.35 no.2
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• pp.92-98
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• 1992

Some physicochemical properties and molecular structure of cow pea, mung bean and acorn starches(mook-forming starches) and red bean, wheat and sweat potato starches(mook-unforming starches) were investigated. Amylose contents of cow pea, mung bean and acorn starch were higher than the others. Cow pea starch was similiar to mung bean starch in gelatinization characteristics by Brabender amylogram but cold viscosity of red bean starch and peak viscosity of sweet potato starch were especially high. Whereas viscosity of wheat starch was low in whole temperature range. Amylose molecules of larger molecular size$(above\;5{\times}10^5\;molecular\;weight)$ of three mook-forming starches were more than shoes of red bean and wheat starch. Chain distribution ratios$(DP\;35{\sim}55\;to\;DP\;10{\sim}20)$ of cow pea, mung bean and acorn amylopectin were higher than thoes of red bean, sweet potato and wheat amylopectin.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.4
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• pp.304-313
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• 2018

The objective of this study was to investigate the resistance starch(RS) content and in vitro hydrolysis index of roasted rice flours for low GI food development. This study used intermediate and high amylose rice varieties containing resistant starch. The intermediate amylose rice varieties 'Ilmi' and high amylose rice varieties, 'Goami4' and 'Dodamssal' were tested. The crude fat and crude protein contents of the rice cultivars ranged 2.12~3.08% and 6.2~7.63%, respectively. The RS and amylose contents of Dodamssal and Goami4 were higher than those of Ilmi. RS content of Ilmi was not significantly different before and after roasting treatment. The RS content of Goami4 before roasting was significantly higher than that of Dodamssal, but the RS content of Dodamssal was higher than that of Goami4 at temperatures above $210^{\circ}C$ of roasting. The soluble starch decreased after roasting in Goami4 and Dodamssal. Starch hydrolysis index (HI) and expected glycemic index (GI) were higher in order of Imi, Goami4 and Dodamssal regardless of roasting treatment. The sensory evaluation showed high scores in Dodamssal for color, flavor, bitter taste, bitter taste, sweet taste and sweetness at $240^{\circ}C$ for 10 min and $210^{\circ}C$ for 30 min. The results of this study indicate that Dodamssal was suitable varieties for powder meal with low GI.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.598-603
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• 2004

Physicochemical properties of crystalline-structured buckwheat starches cultivated and harvested in Taiwan, China, Korea, and USA were compared. X-ray diffraction pattern showed that all starches were type A as are most natural starches. Moisture contents of starches were 6.30-9.58%, and crude protein contents of Taiwanese and Chinese buckwheats were higher than those of Korean and American ones, whereas Korean and Chinese buckwheats had higher fat contents. Blue-value of Chinese buckwheat was highest at 0.39 and that of Korean buckwheat was lowest at 0.32. Amylose content of American buckwheat was highest at 27.6 and that of Korean buckwheat was lowest. Highest water-binding capacity was shown in Taiwanese buckwheat and lowest in American one. Higher amylase contents in Chinese and American buckwheats reduced expansion and solubility. Highest values of viscosity measured by RVA, breakdown indicating process stability, and setback closely connected to retrogradation of American buckwheat resulted in relatively hard gel.

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.24-30
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• 1986

The model foods similar to general Korean foods were prepared by combining starch, protein and moisture, and relationship between their thermal diffusivities and components were investigated. Thermal diffusivity of the model foods tended to be proportional with the moisture content. Under the same level of moisture content of the model foods, thermal diffusivity of the starch foods was higher than that of the protein foods, but no interaction among components was found. The measured values was quite agreed upon with the calculated values with 3.60 residual percent. The regression equations between thermal diffusivity and moisture, protein and starch contents at $20^{\circ}C$ and $60^{\circ}C$ were ${\alpha}20^{\circ}C$ = 0.04911M+0.37355P+3.73072, ${\alpha}60^{\circ}C$ = 0.05353M-0.4766P+4.15136, respectively. The correlation coefficients obtained according to the above equation were $0.9650^{**}$ and $20^{\circ}C$ and $0.9002^{**}$ at $60^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.105-110
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• 1988

The production of single cell protein using the amylolytic fusant obtained from cell fusion between Hansenula anomala and Saccharomyces cerevisiae was studied. The fusant12 strain was selected for single cell protein production from starchy materials among five fusants. Optimum nitrogen source and its concentration for the growth of fusant12 were ammonium sulfate and 0.1%, respectively. Optimum concentration of soluble starch and optimum pH of the basal medium were lord and pH 5.6, respectively. Autolysis of fusant12 was effectively carried out by addition of 5% (v/v) ethyl acetate to the cell suspension and liquidization for 30 min before incubation for 24 hr at 3$0^{\circ}C$. Coculture of fusant12 and non-amylolytic yeast, Torulopsis candida YA-l5, resulted in the increase of the mass as compared to the monoculture of fusant12. The cell mass on tapioca medium was increased about 2.5 times as on soluble starch medium. The content of crude protein and nucleic acid of the dry cell were 39% and 5.8%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1108-1114
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• 2001

This study was conducted to develop semi-solid infant foods using pumpkins. Purees were made from pumpkin and sweet-pumpkin, and were manufactured with blending, steaming or blanching. The moisture content of sweet-pumpkin puree was lower than pumpkin puree, but viscosity, Hunter\`s L, a, b values, $\beta$-carotene and riboflavin contents were higher. Steaming puree from sweet-pumpkin had the highest score in overall-preference and was selected as the ingredient far infant foods. In amylogram, gelatinization temperature was decreased and amylograph viscosity was increased, as the content of modified starch became high. Semi-solid infant floods were prepared with steaming puree from sweet-pumpkin, modified corn starch, rice powder and dairy products such as milk, whole milk powder and skim milk powder. After sterilization of infant foods, Hunter\`s color values were little changed. And the viscosity of infant foods were increased generally, but kept in 3% modified starch group. Sensory evaluation results showed that sweet-pumpkin puree 40%, rice flour 7%, skim milk powder 3% and water 50% was optimum ratio of infant foods.