• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.610-613
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• 1991

The changes of volatile components of cooked rice during storage at $70^{\circ}C$ for 5 hr were investigated. Among more than 100 volatile components of fresh cooked rice, the predominant one was hexanal followed by nonanal, acetone, pentanal, butanal, heptanal, octanal and toluene. These eight components comprised about 55% of the total volatile, which was decreased by half after one hour storage. The amount of major volatile components in Tongil type rice was higher than Japonica rice, but the decrease of volatiles during storage was faster in the former.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.299-303
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• 1992

Methods for harvesting and storage of rice were also originally introduced from the ancient China like other practices of agricultural techniques. Thus, optimum time or rice harvesting was adopted by appropriate draining to prevent the losses, and efficient tools were utilized for harvesting and manufacturing. In addition, our unique and original techniques for rice storage were learned and handed down, which prevented winds and rains, and allowed good ventilation. In the 15th and 16th centuries, treatment of smartweed extracts as emphasized to prevent insect damage for stored barley and rice cutting immediately at harvest was encouraged to prevent shattering of rice grains. In the 18th and 19th centuries, means for prevention of damages by water, insects and rats when grains stored in the field were suggested. Also, studies for ecology of various rice cultivars and storage techniques for a long period of time were necessarily emphasized to assume the optimum time of harvest regionally and to cooperatively work timely.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.136-143
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• 2003

This study was carried out to investigate the quality of bread made with different types of brown rice flours. 20% of the wheat flour from the bread recipe was substituted with the different types of brown rice flours, such as, raw brown rice flour (RBRF), soaked brown rice flour (SOBRF), and sprouted brown rice flour (SPBRF). The loaf volume of the bread: decreased by 3.2%∼7.4% with the addition of the brown rice flours. The "L" value of these breads decreased, while the "a" and "b" values increased. In terms of the texture, the SPBRF bread was the hardest on the 1st day of storage, but it was the least hard on the 5th day of storage. The RBRF bread was the least springy. The SPBRF bread was the most cohesive. The adhesiveness was not significantly different among the breads. In terms of the degree of retrogradation using the ${\alpha}$-amylase method, the SOBRF and SPBRF breads showed a little lesser degree of retrogradation than the control and the RBRF bread. In the sensory evaluation, the control bread obtained high score for crumb color and grain, while the brown rice flours breads obtained high scores for mouthfeel and taste. Overall acceptability, defined by a higher score, was higher for the SOBRF and SPBRF breads than the control bread, which was not significant. Thus, this study showed that processing rice flour was more effective than raw rice flour in substituting wheat flour.

• Food Science and Preservation
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• v.8 no.2
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• pp.140-145
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• 2001

Although the drying times of paddies were significantly shortened by the application of higher drying temperatures, the 12, 10 and 8 hours were needed for the reduction of moisture contents from 23.55 to 15% at the temperatures of 45, 50 and 55$\^{C}$, respectively. Milling yields(MY) and rice rates(HRR) were decreased by increasing of the drying temperature. The MY ratios were 75.50, 75.42 and 75.31% and HRR were 93.28, 92.14 and 91.12% in drying temperature of 40, 50 and 55$\^{C}$, respectively. In the milling processes of tough rice with the used of a milling machine equipped with both of abrasive and friction types in a body, the reduction rates of bran and the occurrence of broken rice increased with the pressures at outlet or the recycled passing tines. In the process for humidified friction whitening of rice, it was found that the optimum addition rate of water for the best quality was the 11.2 liters per tone of white rice.

• Journal of Biosystems Engineering
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• v.16 no.1
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• pp.49-59
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• 1991

A numerical model was developed to predict grain temperature, moisture content, and drymatter loss of rough rice in a grain storage bin. This model simulated conduction, natural convection, and mass transfer occuring inside a storage bin. The results obtained from the study were as follows. 1. The predicticted results agreed well with the measured results. 2. Rough rice could be store safely for one year in Suweon, Dajeon, and Jingu area. 3. Aeration of 5-day was required to control grain temperature and moisture content rise early in Jun and July, respectively.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.409-414
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• 1999

In order to investigate the changes of rice qualities during 4 years storage of paddy stored in ware-house of normal temperature condition. Temperature in warehouse was changed more than 3$0^{\circ}C$ under the influence of average temperature outside of a warehouse. Water content of paddy was not increased over 15% But as average temperature in warehouse was gone up 18$^{\circ}C$ from June to September every years it was supposed that these periods were to be deterioration of rice quality. On investigation of change in paddy it was supposed that these periods were to be deterioration of rice quality. On investigation of change in paddy components during the long term storage, reducing, sugar, amylose, crude protein were increased 0.24%, 19.23%, 7.02% at enterance time to 0.5%, 20.31% 7.46% 4 years later respectively. Max viscosity final visocity and set back value by amylograph were increased 449B,U 610B.U, 161B.U to 493B.U, 715B,U 222B.U but breakdown was decreased 125B.U to 76B.U with the increase of storage period. Gel consistency of rice stored was decreased 44.7mm at enterance time to 39,9mm 4years later. Fatty acid was increased remarkably 4.5KOHmg/100g to 24.4KOHmg/100g. Germination ratio and germ activity of paddy during long-term storage were decreased 97%, 100% to 0%, 0.4% respectively, With the increase of storage period contaminated paddy by molds increased and its by bacteria decreas-ed.

• Korean journal of food and cookery science
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• v.18 no.2
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• pp.211-215
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• 2002

This study was intended to investigate the optimal soaking time of glutinous rice for making jujube Injeolmi, a kind of traditional Korean glutinous rice cake. The jujube Injeolmi was prepared with glutinous rice soaked for various times (2, 4, 6, 8, 10 hr), and the moisture content, chromaticity, sensory qualities and mechanical qualities were measured while storing them up to 72 hr at 20$^{\circ}C$. The moisture content and L-value of jujube Injeolmi were the highest at 8-hr soaking. The a-value was the highest at 6-hr soaking. The hardness was maintained the lowest at the 8-hr soaked sample during storage. The cohesiveness and springiness were not significantly affected by the soaking time. The gumminess was significantly different among the samples during storage. The results of sensory evaluation showed that jujube Injeolmi had the best color at 4-hr soaking and the highest sweetness at 6-hr soaking. The 8-hr soaked glutinous rice gave the highest level of softness, chewiness and moistness in the sample, therefore, 8-hr soaking appeared to be the most desirable method for making jujube Ingeolmi.

• Korean journal of food and cookery science
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• v.23 no.1 s.97
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• pp.50-61
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• 2007

The aim of this study was to determine the optimum amount of astringent persimmon concentrate to add to rice(polished rice, brown rice, and black rice) flour in the preparation of GamJeopyeon (persimmon rice cake). The moisture contents of polished rice, brown rice, and black rice persimmon Jeolpyeon were 50.37${\sim}$51.65%, 49.52${\sim}$52.44%, and 48.82${\sim}$51.87%, respectively. With increasing astringent persimmon content, the L value of all of the Jeolpyeon decreased, whereas the values of polished rice and brown rice persimmon Jeolpyeon increased. The b values of polished rice, brown rice, and black rice persimmon Jeolpyeon were the highest at addition levels of 8%, 4%, and 12%, respectively. In the mechanical textural evaluation, the hardness of polished rice and brown rice, persimmon Jeolpyeon decreased with increasing astringent persimmon concentrate content during storage time, and was the highest at the 0% addition level in black rice Jeolpyeon after 2 days storage. In the sensory evaluation, the overall acceptability of polished rice, brown rice, and black rice persimmon Jeolpyeon was higher at 4, 8, 12, and 16% compared to the 0% addition level. According to the above study. Jelopyeon made with the addition of up to 16% astringent persimmon concentrate to polished rice, brown rice, and black rice flour was found to be the best recipe in terms of overall acceptability and textural qualities.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.99-105
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• 2008

Laver-wrapped rice and laver-wrapped rice containing a vinegar blend (vinegar:sugar:water:salt = 5:2:2:1) were prepared and their degrees of aging from 10 to $30^{\circ}C$, total cell numbers, and total coliforms were examined and compared. The total cell numbers of the laver-wrapped rice increased to 1 log cfu/g at 36 hours, and the total cell numbers of the laver-wrapped rice with vinegar had increased to within 48 hours. At $20^{\circ}C$ for 24 hrs, the total cell numbers for the laver-wrapped rice had increased to 5 log cfu/g: whereas trhe total cell numbers of the laver-wrapped rice with vinegar(5ml of vinegar marinade mixed into 100g of steamed rice), stored at the same conditions had not increased. In the vinegar-marinated rice (2ml/100g rice), microorganisms appeared at 18 hours. However, at the concentration of 5ml/l00g of rice, microorganisms were not observed at 24 hours. Coliforms did not appear in the laver-wrapped rice nor in the laver-wrapped rice with vinegar(prepared at 10ml/100g) until 48 hours. When stored at 10 and $20^{\circ}C$, no microorganisms were found in the laver-wrapped rice with vinegar until 48 hours, respectively. However, at $30^{\circ}C$, microorganisms were observed in the laver-wrapped rice from 24 hours, and from 48 hours in the laver-wrapped rice with vinegar. These results suggest that laver-wrapped rice should be consumed within one day. The number of microorganisms inside the laver-wrapped rice reached 6 log cfu/g by 24 hours, but the increase in the laver-wrapped rice with vinegar was slower. The aging(% damaged starch) of the laver-wrapped rice with vinegar(5ml/100g the rice) stored at $20^{\circ}C$ was reduced, with 3% damaged starch at 24 hours. Consumer evaluations revealed that the laver-wrapped rice prepared with 5ml of the vinegar blend received higher scores for flavor, taste, texture, and overall acceptance as compared to the control. In particular, significantly higher scores were given for taste, texture, and overall acceptability. In summary, the laver-wrapped rice with vinegar had an extended shelf-life(more than 1 day) at storage temperatures of $20-30^{\circ}C$, as well as reduced retrogradation. In addition, based on consumer evaluations, adding vinegar to laver-wrapped rice laver is effective for increasing overall acceptability.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.498-503
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• 1988

Rice and rice flour were stored at $13^{\circ}C$, room temperature$(17-28^{\circ}C)$ and $38^{\circ}C$ for six months and the changes in physicochemical and organoleptic qualities were investigated to determine the preservability. Fat acidity increased rapidly up to 60 days at room temperature and 45 days at $38^{\circ}C$ and thereafter it increased slowly. At $13^{\circ}C$, it increased constantly and slowly throughout the storage. In the changes of Hunter's color for the rice and rice flour, L-value was decreased, but ${\Delta}\;E-Value$ was increased. In amylograph properties, initial pasting temperature, maximum viscosity and breakdown were all increased. Quality of stored rice was a little superior to rice flour, but there were not significantly different among them.