• Korean journal of food and cookery science
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• v.18 no.5
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• pp.548-555
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• 2002

This study was carried out to investigate the quality characteristics of Baiksulgis made of imported rice(Thai and Chinese rice, harvested in 1998) and domestic rice(Chuchung byeo, harvested in 1998 and 1997). Moisture content, color value, yields of reducing sugar by $\beta$-amylase reaction, texture and sensory properties of Baiksulgis were measured. Moisture contents of rice flour and Baiksulgi made of Korean rice harvested in 1997 were highest and those of Thai rice were lowest among the samples. This tends were also seen during storage. Lightness and redness of Baiksulgi made of Thai rice were lowest and yellowness of Baiksulgis made of Korean rice harvested in 1997 and Chinese rice were higher than those made of other rices. Yield of reducing sugar by $\beta$-amylase reaction was highest in Baiksulgi made of Korean rice harvested in 1998 and lowest in Baiksulgi made of Thai rice. And the value decreased less than half of initial value after 24 hour storage. Adhesiveness of Baiksulgi made of Thai rice was zero and cohesiveness, chewiness and gumminess of that were very low. This results showed that Baiksulgi made of Thai rice was lack of chewy texture and this trend was more apparent as the storage time increased. In sensory tests, Baiksulgi made of Chinese rice had most yellowish color and that made of imported rice such as Chinese and Thai rice had more coarse texture than that made of domestic rices. off odor was lowest in Baiksulgi made or Korean rice harvested in 1997 and sweet taste was lowest in that made or Thai rice. Hardness adhesiveness, moistness and chewiness of Baiksulgi made of domestic rices were much higher than those made of impoted rices, and these results showed that Baiksulgi made of domestic rices had acceptable texture. Baiksulgi made of Thai rice showed the lowest acceptability due to lack of above textural characteristics and it was needed to add the material to modify the texture of that.

• Journal of Food Hygiene and Safety
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• v.13 no.1
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• pp.47-52
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• 1998

A rice cultivar (Japonica type), Cheong-cheong, was used to examine the ability as a substrate for aflatoxin production. Brown rice samples were inoculated with Aspergillus parasiticus, stored at various conditions, and observed the production of aflatoxin $B_1$ during storage. Enzyme-linked immunosorbent assay (ELISA) was performed to detect aflatoxin $B_1$ in the samples. A temperature of $28^{\circ}C$ favored the aflatoxin production in the samples. Remoisturizing brown rice to 15.8% encouraged the fungus to produce the aflatoxin significantly (p$B_1$ production in rice, and also indicated that other factors such as husking and storage periods were also risk determinants. This study provided evidence that rice could be an efficient medium for aflatoxin production.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.4
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• pp.370-378
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• 2004

The purpose of this study was to investigate the effect of added nutriprotein and rice powder as a plasticizer on physicohemical property, texture property of Backsulgi. In the physicochemical property, the content of proximate composition of nutriprotein was measured as 6.1% of moisture, 3.6% of carbohydrate, 84.3% of crude protein, 0.6% of crude lipid, 5.4% of ash. The raw material of rice powder was measured as 9.6% of moisture, 83.7% of carbohydrate, 6.0% of crude protein, 0.4% of crude lipid, 0.3% of ash. Swelling power and pore ratio of the control were 78.53% and 72.42%, and tended to increase as the amounts of nutriprotein and plastic rice powder increased. Aging by Avrami eguation retarded in Backsulgi added 10% plastic rice powder than rice powder Backsulgi. All the samples added 2, 4, 6, and 8% nutriprotein at the temperatures of 20 were more effective than others on aging. In texture properties, cohesiveness and springiness were not significantly changed by adding nutriprotein and not significantly changed during the storage period in all samples. Hardness and gumminess decreased by adding 2∼8% nutriprotein and increased during the storage period in all samples. Springiness and gumminess decreased by adding 40% plastic rice powder and increased during the storage period in all sample. Cohesiveness and hardness decreased by the increase of plastic rice powder. The texture characteristics by rheometer showed that Backsulgi with nutriprotein and plastic rice powder exhibited lower in hardness than the control, indicating that nutriprotein and plastic rice powder were effective in retarding retrogradation, which is better when storage time became longer.

• Food Science and Preservation
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• v.6 no.3
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• pp.281-285
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• 1999

Physical and chemical changes of black rice cake were investigated to determine its packaging material during storage. Black rice cake was packaged with polyethylene(PE) or polypropylene(PP) film and stored in RH 65% at 20$^{\circ}C$ for 5 months. There were no differences between PP and PE films for color, hardness and rancidity during storage, while weight change and water activity were slightly different between two films. Weight and water activity of black rice cakes packaged with PE or PP were increased during storage. Weight change and water activity of PE were slightly higher than those of PP. In conclusion, quality changes of black rice cake packaged with flexible packaging materials were little different between PP and PE during storage.

• Journal of Environmental Health Sciences
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• v.29 no.4
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• pp.48-54
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• 2003

This study investigated retrogradation properties of Jeungpyun substituted for cereals with dietary fibers of 60% of brown rice, and barley. Quality changes during storage periods of the functional Jeungpyun, were studied using $\alpha$-amylase iodine enzyme digestion methods, X-ray diffraction patterns, and differential scanning calorimetry (DSC). The barley substituted samples showed significantly lower retrogrdation rates than those of control when examined by $\alpha$-amylase method. The Relative crystallity by X-ray diffraction patterns had typical A type in all samples with appealing big crystallity around its diffraction angle 23$^{\circ}$degrees as storage periods were increased. The brown rice and barley Jeunpyun made smaller crystallity than that of control, representing slower retrogradation rates. The batter controls had significantly lower ΔH than the other compared samples when measured by DSC, but had significantly higher ΔH after 30 days of storage, implying that the control required more energy for regelatinization after the 30 days of storage.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.45-53
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• 1999

Physicochemical and sensory characteristics of cooked rice during warm-keeping with different temperature $(70,\;75,\;80^{\circ}C)$ and period (0, 6, 12, 24, 48 hr) were investigated. As the storage temperature increased, sweet flavor, glossiness, moistness, taste and moisture content decreased but off-flavor, color and sensory and texturometric hardness increased. This trend was significant with storage period. As the storage time and temperature increased, yellowness(b) measured by Hunter color difference meter increased while lightness(L) and whiteness decreased. Degree of retrogradation of cooked rice during storage increased, particularly did in cooked rice stored at $80^{\circ}C$. Cooked rice stored at 70 and $75^{\circ}C$, 6 hr had the least changes in flavor and appearance but more changes in them longer storage time. Cooked rice stored at $80^{\circ}C$ had rapid changes in flavor, appearance and texture at initial state of storage. These results showed that the changes in moisture content of cooked rice stored at various conditions had the most important effect upon sensory characteristics of cooked rice.

• Applied Biological Chemistry
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• v.40 no.5
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• pp.422-426
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• 1997

The effect of sucrose fatty acid ester(SE,{\;}$0{\sim}5%,{\;}w/w)$ and oligosaccharide(OS,{\;}$0{\sim}1.0%,{\;}w/w)$ additions on texture properties, hardness(H), stickiness(-H), stickiness/hardness(-H/H) and elastic recovery (b/a) of cooked rice stored at $20^{\circ}C$ were studied. The H of stored cooked rice decreased with increasing storage time. The addtion of SE and OS showed lower H value than control throughout the storage period up to 12hrs and after 8hrs of storage time, respectively. The -H of stored cooked rice increased with increasing storage time. The -H value of SE added cooked rice showed much lower than that of the control in the early stage of the storage and then almost the same value as that of control. The control and SE or OS added cooked rice resulted the value of -H/H between 0.15 and 0.20, which had been found as acceptable textural parameters, after 10hrs of storage at $20^{\circ}C$. The b/a of stored cooked rice decreased with increasing storage time, but was not significantly affected by additives. After 15 days of storage at $4^{\circ}C$, the addition of SE had greater effect on the reduction of hardness of stored cooked rice than that of OS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.383-389
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• 2012

The objective of this study was to develop and standardize a preparation method for low-salt yacon jangachi using rice wine lees. The proximate composition of yacon was 81.08% (moisture), 0.77% (crude protein), 0.14% (crude lipid) and 0.70% (crude ash). In order to determine the preferred sodium concentrations of soaking solution and rice wine lees, we investigated the quality characteristics of yacon jangachi during storage for 50 days at $18^{\circ}C$. The salinity of yacon jangachi using rice wine lees with 2% and 4% salt increased with storage time, but the salinity did not rise above 3% during storage for 50 days. The salinity of rice wine lees with 4% salt decreased during storage time. a and b color values along with sheared force of yacon jangachi increased as storage time increased, but L color value was reversed. In the sensory evaluation, the color preference for yacon jangachi increased during storage time, and the taste preference was highest at day 30. The flavor preference decreased during storage time, but the texture preference was reversed. In the sensory evaluation of overall preference, yacon jangachi using rice wine lees with 0% salt decreased at day 30, whereas yacon jangachi using rice wine lees with 2% and 4% salt increased during storage time. In conclusion, the salinity of yacon jangachi stored for 50 days with 4% salt did not rise above 3%, and softening was not observed.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.878-885
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• 1996

The brown rice drying is effective for energy saving and cost reduction. However, deterioration after drying is one problem, because the skin damage occurs during the drying. So, the measures to preserve the quality has been investigated. One of major quality deteriorations is the oxidation of fat which is contained in the bran layer. So, milling should be carried out to remove the fat as soon as possible after brown rice drying. And the low temperature storage is also worth to be examined for prevention of oxidation. The effect of skin damage on the increase of fat oxidation was clarified. For the grain of skin damage, the increased of fatty acid vaule was remarkable after 70 days elapsed from occurrence of skin damage even in $15\;^{\circ}C$ condition. Therefore it is impossible to keep grain as brown rice form after brown rice drying. For the clean rice and excessively milled rice, the quality can be preserved even in high temperature of $30\;^{\circ}C$. Therefore the brown rice drying can b applied practically using the clean rice technique.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.63-68
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• 1996