• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.35-41
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• 2020

This study was conducted to develop the efficient system for starch hydrolysis suppression using rutin, quercetin and dietary fiber through the statistical mixture design. The three components were replaced with wheat flour at the level of 10% and the mixed gel with three components was characterized by in vitro starch digestion. The mixture design was applied by simplex-centroid experimental model. The quadratic model (R²=0.86) was well fitted and the obtained regression equation indicated that the significant positive effects was observed in the quercetin and fiber mixture. Based on the statistical results, the best mixing ratio of quercetin and fiber was 72: 28 that led to the lowest predicted glycemic index (pGI). Their interactions on the pGI of starch digestibility were clearly visualized in the 3D surface plot. These results suggested that the mixture of quercetin and fiber interact strongly with wheat flour, consequently retarding starch hydrolysis by 15%.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.731-738
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• 2021

This study investigated the physicochemical properties of rice starch isolated from broken rice using alkaline steeping (AKL) and enzymatic digestion (ENZ) methods. Broken rice starch (BRS) by AKL and ENZ possessed crude protein contents (0.6-1.4%) acceptable to commercial products of native starch and belonged to an intermediate amylose rice starch. AKL-BRS and ENZ-BRS showed a typical A-type crystal packing arrangement with small variations in their relative crystallinity. ENZ-BRS exhibited higher gelatinization onset and peak temperatures, and a narrower gelatinization temperature range than AKL-BRS, indicating that annealing occurred in ENZ-BRS. Lower swelling power and solubility were generally observed in the ENZ-BRS. ENZ-BRS also showed slower viscosity development, higher peak and trough viscosities, and lower breakdown, final, and setback viscosities, compared to those in AKL-BRS. These results are ascribed to the annealing phenomenon in ENZ-BRS. Overall, BRS from cheap broken rice using AKL and ENZ could contribute to the expansion of rice starch utilization in food and non-food industries.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.475-478
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• 1994

The hydrolyzability of chemically modified starches and ramen staches was determined by hog pancreatic ${\alpha}-amylase$ in vitro test. The extents of hydrolysis were 64.5% and 59.3% in native and acetylated potato starch, 70.5% and 60.4% in native and hydroxypropylated corn starch, and 65.2% and 57.3% in native and hydroxypropylated high amylose corn starch, respectively. The hydrolysis extents of waxy corn starch derivatives were shown in the descending order of pregelatinized (74.3%)>native (72.1%)>acetylated (66.5%)>acetyl distarch adiphate (56.4%)>hydroxypropyl distarch phosphate (50.7%). In the test on starches of container and regular ramen cooked by practical way, no significant difference was observed between ramen products of five different makers. Although the hydrolysis rate and extent of chemically modified starches were lower than those of native starches, the digestibility of ramen seemed to be not affected in the common diet as the use level of modified starch was relatively low.

• Korean Journal of Human Ecology
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• v.2 no.2
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• pp.29-38
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• 1999

저항전분(RS)은 건강한 사람의 소장에서 소화되지 않는 전분이나 전분질 식품의 부분이다. 저항전분은 4가지 형태로 구분하는데 RS 1은 물리적으로 효소와 만나지 않는 부분, RS 2는 생전분으로 감자, 바나나와 고아밀로오스 옥수수전분, RS 3는 노화된 전분 그리고 RS 4는 화학적으로 변성시킨 전분이다. RS 함량은 열에 안정한 $\alpha$ -아밀라아제나 pancreatin, pancreatic $\alpha$ -아밀라아제와 미생물에서 분리된 아밀라아제 등을 이용한 몇 가지 방법에 의해 분석되고 있다. RS는 대장에서 미생물에 의해 발효되어 단쇄지방산을 생성하는데 특히 부티릭산이 생성된다. 아세트산이나 프로피온산은 간의 대사에 영향을 주며 부티릭산은 항 종양(항 대장암) 특성이 있다. RS는 소화가 되지 않아 저열량원이므로 당뇨병 환자나 운동에 의한 혈당 조절이 필요할 때 조절능력을 갖는다. RS가 건강에 중요한 인자임이 알려지면, 건강을 위해 매일 섭취량의 증가를 권장해야 할 것이다.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.526-535
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• 1988

To estimate the effect of preventing the Maillard reaction between casein and glucose coated by freeze drying with corn starch slurry or mixture slurry of corn starch and sucrose, the reactants were treated into five groups of nonbrowning material(control), uncoated browning material, browning material coated casein alone with starch slurry, browning material coated both of reactants with starch slurry and browning material coated both of reactants with mixtrue slurry. All samples had a moisture content of about 15%. Browning reaction was carried out by storage for 30 days at $37^{\circ}C$, 67% RH. In vitro available lysine contents were decreased by the browning regardless of coating the reactants and were higher about 20.5% in the browning materials coated with mixture slurry than in the uncoated browning materials. Fructosyl-lysine contents were increased about tenfold by the browning regardless of coating and were decreased about 15.8% in the browning materials coated with mixture slurry as compare with the uncoated browning materials. The materials showing the greatest resistance to the browning reaction in the coated materials were those in which both of reactants were coated with the mixture slurry of corn starch and sucrose.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.749-755
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• 2021

The objective of this study was to investigate the physicochemical properties of rice starch extracted from stale rice using alkaline steeping (AKL) and improved enzymatic digestion (iENZ) methods. The crude protein content (0.5-0.7%) of stale rice starch (SRS) was less than 1% by iENZ, but not so when measured by the existing ENZ methods. SRS is an intermediate amylose rice starch. AKL-SRS and iENZ-SRS exhibited typical A-type crystal packing arrangements with similar relative crystallinities. iENZ-SRS showed higher gelatinization onset and peak temperatures with a narrower gelatinization temperature range, compared to those of AKL-SRS, indicating that iENZ annealed SRS. Thus, iENZ-SRS exhibited lower swelling power and solubility, and higher pasting viscosities with delayed viscosity development. Overall, the use of stale rice as a rice starch source could make economical production of rice starch possible, and iENZ may diversify rice starch characteristics, which expands the utilization of rice starch in food and non-food industries.

• Applied Biological Chemistry
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• v.21 no.1
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• pp.16-21
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• 1978

In order to determine optimum condition for the Ko-Choo-Jang (red-pepper-paste) processing, chemical analysis, mixed ratio, and sensory teat, resulted as follows. 1. The best nutritional value could be obtained after three hours at $60^{\circ}C$, which proved to be the optimum temperature in koji digestion of starch paste. 2. The component ratio of wheat flour to koji-powder was two to one giving the best digestion. 3. The mixing ratio of salt and red-pepper-powder and flour-koji was determined as 1 : 1.5 : 3 by sensory tests. 4. The highest reducing sugar content appeared in a digested mixture using glutinous rice as a starch source and the reducing sugar increased continuously with decreasing, total sugar content in almost every mixture of starches. 5. As a starch source, glutinous rice powder produced the highest total sugar in the beginning stages, however, after 10 day's curing produced less sugar than rice powder. 6. The order of total nitrogen content in the cured paste was recorded as wheat-flour, rice-powder, corn-powder, glutinous-powder, barley-powder, and sweet potato-starch. 7. Amino-nitrogen was increased with curing and the highest, value was observed in the case of wheat flour. 8. In sensory test, Ko-Choo-Jang made of glutinous rice-powder resulted in the best taste.

• Korean Journal of Food Science and Technology
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• v.49 no.1
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• pp.1-7
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• 2017

Molecular structure, physicochemical properties, and in vitro digestibility of starch from Korean rice cultivars for special uses (Baegjinju 1, Hanareum, Deuraechan, and Goami 4) were investigated. The starch from Baegjinju 1 had the lowest amylose content (9.7%) and Hanareum, Deuraechan, and Goami 4 had intermediate amylose (20-25%) contents. Baegjinju 1 had a lower proportion of short amylopectin branch chains than the other rice starches. Hanareum had the lowest relative crystallinity and the highest intensity ratio of $1047cm^{-1}/1022cm^{-1}$ among the rice starches. The starch from Goami 4 had a higher pasting temperature and lower gelatinization enthalpy than the other rice starches. Peak viscosity of rice starch from Baegjinju 1 was substantially higher than peak viscosity of other rice starches. Rice starch from Baegjinju 1 had significantly higher rapidly digestible starch content and lower resistant starch content than other rice starches, whereas there was no significant difference in resistant starch content among the rice starches.

• 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.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.135-142
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• 2014

Physicochemical, pasting, and digestion properties of sweet potato starches from 11 Korean cultivars were investigated. Starch granules were variably oval, round, polygonal, spherical, and bell-shaped, and of 10.2-15.3 ${\mu}m$ in mean particle diameter. Amylose contents varied from 12.3 to 17.4%. A similar chain length distribution of amylopectin was found in each of the cultivars. The portion of $B_3$ correlated with the degree of amylose leaching. Thermal properties determined by differential scanning calorimetry showed high values of gelatinization temperatures in Shinyulmi and Jeungmi starches, but a relatively low value in Daeyumi starch. All starches exhibited a Ca-type diffraction pattern. Differing patterns were observed in swelling factors, depending on temperature. The contents of rapidly digestible starch, slowly digestible starch, and resistant starch ranged from 9.6-17.4, 31.4-45.6, and 35.7-62.8%, respectively. In Rapid Visco Analyser profiles, differences were observed in pasting parameters such as pasting temperature, peak viscosity, final viscosity, and breakdown.