• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.461-467
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• 1993

The purpose of this study was to investigate the physico-chemical properties of potato starch heated with microwave. Two types of potato starches are prepared; in group A raw potato starch was heated with microwave and in group B potato starch was isolated from potato heated with microwave. Both groups were exposed to the microwave energy in a 560 W, 2,450 MHz oven for 60, 120, 180 and 300 seconds. As the microwave heating time took longer, free lipid decreased and bound lipid increased in both groups. The shape of starch granules, birefrigence and X-ray diffraction pattern were not changed much by microwave heating in both groups. Water binding capacity increased, but amylose content, swelling power and solubility decreased as the microwave heating time took longer. It was also found that the extent of decreases in swelling power and solubility were different between group A and group B.

• Bulletin of Food Technology
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• v.14 no.2
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• pp.109-115
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• 2001

• Journal of Ginseng Research
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• v.8 no.2
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• pp.124-134
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• 1984

Ginseng root starch, prepared by conventional method, contained crude lipid of 0.5%, crude protein of 0.4%, crude mineral of 0.17% and phosphorous of 12.5mg% as noncarbohydrate constituents. The amylose content of ginseng root starch picked in Summer (May to August) and Winter (November to March) was 32-35% and 15-20%, respectively, and it was decreased with a growing preiod of ginseng. The blue value, alkali number and ferricyanide number of the starch were 0.14-0.17, 8.50 and 0.781, respectively. The molecular weight of amylose in the starch was estimated to be 1.27-7.95${\times}$105 by means of periodate oxidation, and the degree of branching and glucose unit per segment of amylopectin were 3.50-3.53% and 28.3-28.5, respectively, The starch content of ginseng root was decreased when dried under sunlight and stored at 5$^{\circ}C$ for twenty days. In contrast, sucrose content in the root was increased from 3.8% in fresh state to 11.5% during storage at the above condition. In the other hand, starch was converted to maltose by heating at temperature above 70$^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.633-641
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• 1991

Mook, a traditional gel food in Korea, has been made from mainly acorn, buckwheat, and mungbean starches (Mook Starches). Corn, rice, wheat starches (Non-Mook Starches) are not used due to their weak gelation power. In order to know the effects of properties of starch on gelation, some physicochemical properties, molecular structure, and starch lipid of these six starches were investigated and compared with gel hardness. Both amylose content and gel hardness of starches were in order of mungbean, acorn, buckwheat, wheat, corn, and rice and these two parameters showed a very good correlation (r=0.95). The amyloses of Mook Starches had larger molecular size (${\overline}D.P._{n}=1,080{\sim}1,580\;vs\;670{\sim}1,120$ for Mook Starches and Non-Mook Starches, respectively), more average number of chain ($2.9{\sim}5.4\;vs\;1.7{\sim}2.5$), and shorter average chain length ($290{\sim}390\;vs\;390{\sim}450$) than those of Non-Mook Starches. Also, Mook Starches had longer average chain length ($22.2{\sim}22.6\;vs\;18.9{\sim}21.3$) of amylopectin and less starch lipid content ($0.12{\sim}0.49\;vs\;0.68{\sim}1.26%$) than Non-Mook Starches. These properties had good correlations with gel hardness (r=0.76-0.84). Consequently, the gelation power of Mook Starches was thought to be derived from their high amylose content and other properties of starches.

• Journal of Nutrition and Health
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• v.30 no.3
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• pp.252-265
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• 1997

This study was performed to investigate effect of dietary fibers in rice and barley on glucose, lipid and cadmium (Cd) metabolism in the rat. Fifty-six male Spague-Dawley rats weighing 244.6$\pm$2.7g were blocked into eight groups according to body weight and raised for four weeks with diets containing 0 or 0.04%(w/w) CdCl2 and four different carbohydrate sources, starch, rice flour, barley flour and mixture of rice and barley flour(7 : 3, w/w). Total dietary fibers and $\beta$-glucan contents of barley were about three times higher than those of rice (10.75% vs. 3.94%, 3.11% vs. 1.06%, respectively). Food intake, weight gain, food efficiency ratio, liver and kidney weights were lower in Cd exposed groups, and barley group among Cd exposed animals showed highest weight gain, food efficiency ratio and organ weights. Fasting serum glucose levels were not significantly different among groups, Serum cholesterol level was lowest in Cd exposed barley group. Serum HDL-cholesterol level was higher in none-Cd exposed starch and barley groups, and HDL-cholesterol : total cholesterol ratios were higher in none-Cd rice and mixed flour groups than other groups. Liver total lipid and triglyceride levels were lowest in barley groups regardless of Cd administration. Fecal total lipid, cholesterol and triglyceride excretions were high in barley and mixed flour groups. Liver Cd concentrations were low in Cd exposed barley and mixed flour groups. In Cd exposed barley group, fecal weight and Cd excretion were highest and Cd retention ratio was lowest among groups. Small intestine metallothionein(MT) concentration was highest in Cd exposed rice group, and kidney MT concentration was highest in Cd exposed barley group. In conclusion, cereals showed different effects on lipid and Cd metabolism that might be mediated by dietary fibers in cereals. Especially $\beta$-glucan-rich barley group showed greatest lipid and Cd lowering effects by increasing fecal lipids and Cd excretions.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.23-31
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• 2002

Effects of autoclaving-cooling cycled waxy rice(Hwasunchalbyeo) starch(ACW) on textural and sensory properties of Injulmi were investigated. The protein, ash and lipid contents of waxy rice flour were higher than those of waxy rice starch and ACW. The RS level of ACW was 8.21%. By increasing ACW content added to Injulmi, hardness and adhesiveness of Injulmi decreased, Hunter color L and a values increased and b values decreased. The sensory test showed that the hardness of Injulmi decreased, but springiness and adhesiveness increased by increasing ACW content to Injulmi. Overall Qualities of injulmi added with ACW up to 20% were similar to the non-added Injulmi.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.207-211
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• 2008

In order to understand the difference in rice eating quality, two rice varieties having different eating qualities were examined from the correlation between palatability score (Toyo value) and components of lipid in rice endosperm. We also analyzed the relationship between lipid properties and physicochemical characteristics of milled rice. Major fatty acids of milled rice starch-lipids, known to exist as inclusion complexes with amylose in starch granules, were palmitic (38.25% in Gopum and 39.75% in Palgong) and linoleic aicds (33.13% in Gopum and 31.93% in Palgong). In addition, the unsaturated fatty acid contents of rice endosperm showed a significant relationship with palatability. Plant sterols in two rice samples were identified, Gopumbyeo of good eating quality had high contents of squlaene and cycloartenol and similar contents of campesterol, stigmasterol and sitosterol. There were significant differences in pasting properties of rice flours and starches between the two cultivars. These results suggested that rice lipids impact on pasting properties after cooking, subsequently relating to palatability.

• Nutrition Research and Practice
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• v.6 no.1
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• pp.16-20
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• 2012

The effects of retrograded rice on body weight gain, gut functions, and hypolipidemic actions in rats were examined. When the retrograded rice was produced by repetitive heating and cooling cycles, it contained significantly higher amounts of resistant starch ($13.9{\pm}0.98%$) than is found in common rice ($9.1{\pm}1.02%$) (P < 0.05). Sprague-Dawley rats were fed either common rice powder or retrograded rice powder, and mean body weight gain was significantly lower in the retrograded rice group (P < 0.05). The liver weight of the retrograded rice group ($14.5{\pm}0.5\;g$) was significantly lower than that of the common rice group ($17.1{\pm}0.3\;g$, P < 0.05). However, the weights of other organs, such as the kidney, spleen, thymus, and epididymal fat pad were not significantly affected by rice feeding. Intestinal transit time tended to be lower in rats fed retrograded rice when compared to rats fed the common rice, but the difference was not significant. The retrograded rice diet significantly increased stool output when compared to that in the common rice powder diet (P < 0.05), whereas fecal moisture content (%) was significantly higher in the retrograded rice group ($23.3{\pm}1.2$) than that in the common rice group ($19.1{\pm}1.2$) (P < 0.05). The retrograded rice group had significantly lower plasma cholesterol (P < 0.05), liver cholesterol (P < 0.05), and triacylglycerol contents in adipose tissue (P < 0.05) when compared to those in the common rice group. In conclusion, retrograded rice had higher resistant starch levels compared with those of common rice powder, and it lowered body weight gain and improved lipid profiles and gut function in rats.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.556-561
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• 1989

Thermal properties of amylose-lysolecithin (AL) complex, amylose content and effect of lysolecithin on the gelatinization of rice starch were investigated by Differential Scanning Calorimetry (DSC). The melting temperature of AL complex was near to $108.5^{\circ}C$ and the melting enthalpy was about 1.0cal/g. The gelatinization temperature of rice starch was not affected by adding lysolecithin. However, the enthalpy of gelatinization was decreased. The amylose contents in rice varieties were calculated from melting enthalpy of AL complex. The amylose contents for Indica and Japonica types of rice were in the range of 16-19%, which were in good agreement with those determined by iodine binding method. Significant differences were not observed in the amylose contents between Indica and Japonica varieties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.143-152
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• 1989

Some sugars and proteins were mixed with yellow corvenia lipids, soybean lipids or see yolk lipids to study the influence of the sugars or proteins on lipid oxidation and browning in dry and wet system during kept at $40^{\circ}C$. In the yellow corvenia lipids mixed with various food components, peroxide value(POV), carbonyl value(COV) and brown pigments were much higher than the case that soybean lipids or egg folk lipids were mixed. In terms of the food components, they appealed high in glucose, sucrose and starch but low in albumin and casein. When the soybean lipids were mixed, POV appeared low in all these maxture. COV and brown pigments appeared high in glucose, sucrose and starch but low in albumin and casein. In the case of egg york lipids, POV appeared lower than that of soybean lipids but COV and brown pigments were similar. In the starch mixture of three lipids in wet system, POV and COV in yellow corvenia lipids appealed lower, but appeared higher in soybean lipids and egg yolk lipids than those in dry system. Brown pigments appeared similarly with the case in dry system. And the all mixtures of casein in wet system, POV and COV appealed lower thanthose of the dry system, but brown pigments appeared high.