• Food Science and Biotechnology
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• v.17 no.1
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• pp.180-183
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• 2008

Digestion properties of 3 types of cereals, white rice, brown rice, and barley, were measured after cooking or grinding. Regardless of the processing methods, white rice showed the highest rate and the greatest extent of digestion, whereas barley showed the lowest values. During the early digestion period, cooked white rice kernels had a larger k (kinetic constant) value than uncooked white rice flour, indicating that cooking induced faster digestion than grinding. In the case of brown rice and barley, the cell wall in cooked kernels remained intact and resulted in a lower k values than those of uncooked flour. However, after 3 hr of digestion, the total digestion extent was greater for the cooked brown rice and barley than that for uncooked flours. The high content of slowly digestible starch (SDS) in cooked brown rice and barley might be due to the starch fraction which was protected by the cell wall. The resistant starch (RS) content, however, was greater for the uncooked flours than that for cooked kernels. The cooked kernels of 3 cereal samples tested showed higher glycemic index (GI) values than the uncooked flours.

• 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.

• Korean journal of food and cookery science
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• v.23 no.3 s.99
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• pp.314-320
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• 2007

The objective of this study was to investigate the effect of grain size on the physicochemical properties of rice porridge. Here, the grain size of the rice was classified as whole grain, half grain, and flour by traditional Korean cooking methods. The viscosity of the rice flour porridge was highest for the among the three different grain size porridges. In the amylographs, the increase in viscosity for the whole grain porridge was higher than that of the rice flour porridge during cooling. The soluble solid and reducing sugar contents of the rice porridges increased according to the rice grain size, while the blue value decreased. The SDI (starch digestion index) increased according to the rice grain size. The RDS (rapidly digestible starch) was highest while the SDS (slowly digestible starch) the lowest in the rice flour porridge. The morphologies of the rice porridges were examined by SEM and showed a smoother surface and more exudated gelatinized granules in the rice flour than in the whole grain rice porridge. In conclusion, rice porridges made from the smallest possible grain size such as flour may be helpful for people with weaker digestive systems such as infants, the elderly, and hospital patients.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.1078-1081
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• 2007

The in vitro digestive properties of 6 domestic noodle products (spaghetti, somyeon, ramyeon, dangmyeon, naengmyeon, and jjolmyeon) were compared after cooking under the manufacture's recommended cooking conditions. The kinetic constant (k), representing the rate of hydrolysis at the initial digestion stage, was highest in the somyeon noodles (0.1151), followed by naengmyeon (0.0954), and was lowest in the spaghetti (0.0421). However, the concentration of starch ($C_{\infty}$) hydrolyzed over 2 hr was not different between the spaghetti (96.22) and the somyeon (96.40), indicating that different digestion behaviors occurred in each type of noodle, even though the amounts of digested starch were similar. The ramyeon, dangmyeon, and naengmyeon noodles showed relatively lower $C_{\infty}$ values than the spaghetti and the somyeon noodles. The spaghetti had the highest amount of slowly digestible starch (SDS, 43%) and the lowest glycemic index (GI, 87.8), whereas the somyeon had the lowest SDS value (9.6%) and the highest or (93.0). The digestibility differences among the noodles were attributed to differences in their flour compositions and manufacturing processes.

• Korean Journal of Community Nutrition
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• v.9 no.4
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• pp.528-535
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• 2004

In order to observe the effects of resistant starches on human glycemic response, nine female university students were investigated using cellulose (CED), resistant starch 3 (RS3D) and resistant starch 4 (RS4D) diets. Each woman's blood sugar and insulin, triacylglycerol and free fatty in plasma concentration were measured at fasting state, then 15, 30, 45, 60, 75, 90 and 120 minute after each test diet feeding. Glycemic indices of the Cellulose diet (CED: 57.9 $\pm3.00$), the Resistant starch 3 diet (RS3D: 52.6 $\pm7.9$) and the Resistant starch 4 diet (RS4D: 52.9 $\pm10.2$) were similar to each other, but they were significantly lower in comparison with those of white wheat bread diet (WWBD: 100). Insulinemic indices of the CED (49.8 $\pm8.2$), RS3D (50.0 $\pm7.3$) and RS4D (72.4 $\pm7.7$) were significantly lower in comparison with the white wheat bread diet (WWBD: 100), but among the dietary fiber diets, the insulinemic index of RS4D was significantly higher than the CED and the RS3D. Plasma triacylglycerol contents of the CED, RS3D and RS4D including WWBD showed gradual increase in tendency after lowering in early stage of each test diet feeding, but not significantly different in each dietary fiber added diet. Plasma free fatty acid contents of the CED, RS3D and RS4D including WWBD showed gradual decrease in tendency after each test diet feeding, but not significantly different by each dietary fiber added diet. In above results, we speculate that resistant starch 3 controls rapid elevation of blood sugar by delaying intestinal digestion and absorption of cellulose, but the result appears to be different from RS4 in comparison. Thus, RS3 intakes may contribute to the diet therapy of diabetic humans, but more studies on RS4 is needed in the future. (Korean J Community Nutrition 9(4): 528∼535, 2004)

• 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%.

• Journal of Korean Medicine Rehabilitation
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• v.30 no.4
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• pp.31-39
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• 2020

Objectives Danggwisoo-san and Jakyakgamcho-tang are frequently prescribed for traffic accident patients in Korea. The aim of this study was to examine index compound analysis, antioxidant activity and amount of starch measurement by extraction method. Methods Danggwisoo-san and Jakyakgamcho-tang were extracted with water and 70% ethanol. Antioxidant activity was measured by 2,2-Diphenyl-1-picrylhydrazyl, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and ferric reducing antioxidant power according to the standard protocol. The contents of the indicator components nodakenin, paeoniflorin, and glycyrrhizin were measured by high-performance liquid chromatography, respectively. All starches were hydrolyzed and then total D-glucose was measured and compared. Results Antioxidant activity was excellent in 70% ethanol in all assays. The index component was jagged because its solubility was different depending on the extraction solvent. Starch content was significantly lower in 70% alcohol extract than water extract. Conclusions The results of this study showed that physiological activities and components are different according to extraction conditions. Each herbal medicine has a suitable extraction solvent. Also, the difference in starch content is an object to be considered as it may affect digestion and absorption.

• Journal of the Korean Society of Food Culture
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• v.24 no.2
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• pp.191-198
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• 2009

The objective of this study was to investigate the effects of different amounts of pumpkin powder on the quality characteristics of hobakpyeon using physicochemical and sensory properties, as well as on its retrogradation rate during storage. As the amount of pumpkin powder increased, the following effects on the quality characteristics were observed: moisture and amylose contents decreased while protein content increased (p<0.05), and in vitro protein digestibility (IVPD) decreased (p<0.05). Levels of slowly digestible starch and resistant starch fractions increased, while the content of rapidly digestible starch decreased. The starch digestion index and rapidly available glucose content also decreased. Among the physical properties, the L-value decreased while the b-value increased (p<0.05). Texture profile analysis revealed that all textural properties except adhesiveness decreased, and presented significant differences in hardness and chewiness (p<0.05). Sensory properties such as color, flavor, and sweetness increased while others such as wetness and chewiness decreased (p<0.05). Effects on the physicochemical properties during refrigerated storage were also compared between the control and 9% hobakpyeon (9%HP). According to the results, moisture content gradually decreased in the 9%HP compared to the control. Amylose content significantly increased in 9%HP whereas no significant changes were observed in the control. In both types of hobakpyeon, IVSD decreased significantly, showing higher values in 9%HP, whereas mechanical hardness increased, showing lower values in 9%HP. The L-value decreased significantly in the 9%HP whereas no significant changes were observed in the control. In conclusion, the above results suggest that hobakpyeon with low IVSD may be obtained by the addition of 9% pumpkin powder, and also showed that pumpkin powder delayed the rate of retrogradation in 9%HP during storage.

• Journal of the Korean Society of Food Culture
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• v.22 no.6
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• pp.820-826
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• 2007

Different types of bap(cooked rice) was cooked using barley or/and SoRiTae with rice as the base. Total(TS), rapidly digestible(RDS), slowly digestible(SDS) and resistant(RS) starch fractions were determined. Other physicochemical properties such as moisture, protein, amylose contents, protein digestion in vitro and color values as well as sensory properties of different bap were also investigated. Cooked rice with SoRiTae(RiSo) showed the highest moisture content of 63.9%, whereas other bap showed simillar content ranging from 62.3-63.0%. Crude protein content of RiSo was the highest, while that of cooked rice(Ri) was the lowest(p<0.05). Amylose content of RiBa was the highest, while that of RiSo was the lowest(p<0.05). In in vitro protein digestibility(IVPD), cooked rice with barley and SoRiTae(RiBaSo) was the highest, while Ri was the lowest, showing no significant difference at p<0.05. In starch fractions, as barley or/and SoRiTae were added to rice, a decrease in RDS content and increases in SDS and RS contents were observed. In addition, starch digestion index(SDI), which derived as an indicator of their in vitro starch digestibility and rapidly available glucose(RAG) value, which determined as a predictor of potential glycemic response decreased. A decrease in L value from RiSo and RiBaSo, which comprised of SoRiTae and increases in a and b values in RiSo and RiBa were observed, respectively. All sensory parameters involving color, glossiness, sweet taste, wetness, roughness, hardness and stickiness were shown to be a significant difference except sweet taste among different bap(p<0.05). L value of instrumental characteristic was negatively correlated with color of sensory characteristic and a value was positively correlated. Significant negative correlation was found between RS content and glossiness, however, positive correlation with roughness and hardness, respectively. These results suggested that cooked rice mixed with barley and SoRiTae contain significant RS and SDS contents and may improve diabetes and hyperlipidemia, due to the lowering RDS and RAG, respectively.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1229-1235
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• 1998

To see the correlation between the rate of in vitro starch hydrolysis and the glycemic index, an in vitro digestion was carried out by incubating the cereal samples for 2 hours with ${\alpha}-amylase$ in dialysis tubing. Also the levels of blood glucose were measured over 2 hours after feeding healthy volunteers with 50 g carbohydrate portions. Hydrolysis area, hydrolysis index (HI) and the dialysate content of carbohydrate throughout the digestion time for barley was significantly below those for other cereals (p<0.05), and unpolished glutinous rice was significantly above (p<0.05). The GI-glucose of barley $(57%{\pm}7)$ to glucose as standard was significantly (p<0.05) lower than those of other cereals whereas the GI-glucose of glutinous rice $(110%{\pm}8)$ was significantly higher (p<0.05) than other cereals. The GI-rice values to rice as standard were $122%{\pm}4$ for glutinous sorghum, $116%{\pm}13$ for job's tear, $115%{\pm}13$ for glutinous millet, $106%{\pm}6$ for unpolished glutinous rice, $102%{\pm}7$ for glutinous rice, $100%{\pm}0$ for rice, $90%{\pm}12$ for unpolished rice, $85%{\pm}6$ for foxtail millet, $79%{\pm}5$ for buckwheat and $63%{\pm}6$ for barley. The GI-rice was significantly correlated to hydrolysis area and HI (r=0.75, p<0.01). It suggests that the in vitro starch hydrolysis offers good potential to predict the in vivo glycemic response of starch foods.