• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.6
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• pp.524-530
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• 1993

The experiment was carried out to investigate the changes in physicochemical properties of milled rice harvested in different year and stored for four to sixty four months. The fat acidity of milled rice increased sharply from four to sixteen months storage, and after then it was increased slowly to sixty four months. Amylose, magnesium, potassium content, and K/Mg ratio of milled rice were not changed by storage duration. Water absorption rates of milled rice at 21$^{\circ}C$ and 77$^{\circ}C$, and alkali digestion value were increased by longer storage duration. Difference of water absorption rate between rice samples was greater during initial forty minutes after soaking at 21$^{\circ}C$ and with longer the soaking time at 77$^{\circ}C$. Shorter gel length of rice flour was found with prolonged storage duration, while peak, minimum, cool, breakdown and setback viscosity of gelatinized rice flour on amylograph were increased along with increasing the storage duration. The volume expansion rate during cooking and degree of iodine coloration of cooking water were higher in the longer stored rice compared with shorter one, and the amount of soluble solid in cooking water was significantly decreased in rice stored longer period.

• 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.

• 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.

• 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.

• 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 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.

• 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.

• 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.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.

• 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