• Journal of the East Asian Society of Dietary Life
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• v.22 no.5
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• pp.684-691
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• 2012

Glutinous rice dduk, traditional Korean rice cake, was prepared using rice(white glutinous rice, brown glutinous rice, black glutinous rice, gaba glutinous rice) as a meal alternative, and each of their quality characteristics were compared. This study had checked sensory tests, color differences, moisture contents, texture characteristics, and storage lives of dduk during storage at room temperature for 6 days. The moisture contents of black glutinous rice dduk scored the highest. For color properties, gaba glutinous rice dduk was darker with a decreased yellow value, whereas its red value was higher comparing with that of brown glutinous rice dduk. The results of the preference test showed that appearance, flavor, texture, and overall preference were the highest in white glutinous rice dduk, whereas black glutinous rice dduk showed the lowest score. The results of the color difference test showed that softness, viscoelasticity, and fineness were the highest in white glutinous rice dduk, whereas black glutinous rice dduk showed the highest difference in color. For individual textural characteristics, black glutinous rice dduk showed the highest score, whereas white glutinous rice dduk showed the lowest scores in hardness, chewiness, and gumminess. In the results of the textural characteristics of dduk during storage, white glutinous rice dduk showed the highest increase in hardness after 48 hours, whereas black glutinous rice dduk showed the lowest increase. White glutinous rice dduk showed the highest increases in chewiness and gumminess. Cohesiveness decreased in all glutinous rice dduk. In the results of fungal occurrence in dduk during storage, black and gaba glutinous rice dduk showed increased fungi occurrence compared with white and brown glutinous rice dduk after 6 days. In conclusion, the overall preference for glutinous rice dduk made from different rice is more affected by appearance or texture than flavor.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.26-32
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• 2003

Rice is one of the most important cereals in the world. Japanese people use about 9 million tons of rice per you. We use rice for cooked rice as staple foods and for processing, such as rice wine (sake), rice crackers and miso fermentation, etc. Palatability, eating quality, of rice is evaluated by the sensory test and various kinds of physicochemical measurements. Japanese National Food Agency started the storage of 1.5 million tones of rice in 1996. We carried out the storage test using high quality rices since 1995 until 1996. As indices for the quality deteriorations of rice grains during the storage, germination ratio, enzyme activities, fat acidity, physical properties of cooked rice were clarified to be useful. We applied colorimetric method for the measurements of fat acidities in the place of titration method. Processing suitabilities of rice differ depending on the products. Low amylose rice is more suitable for soft rice crackers and high amylose rice is preferred more for rice noodle. Pre-cooked rice products, such as frozen cooked rice, retort-pouched rice and aseptic rice, are increasing recently in Japan. In addition to above-mentioned physico-chemical tests, NIR spectroscopy,“Midometer”and“Taste sensor”are novel and useful to evaluate eating quality and processing suitabolities. Recently, rice wholesalers and retailers have been obligated to display the name of cultivar, location of cultivation and the year of production of rice grains which they sell by the Japanese Agricultural Standard Law (JAS). In order to detect the dishonest labeling of rice cultivars, we developed new cultivar identification method based on DNA polymorphism.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.427-436
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• 2001

The effects of storage form (paddy and milled rice) and storage period (1, 2, and 3 years) of rice at low temperature $(4^{\circ}C)$ on physicochemical properties of milled and cooked rice and sensory characteristics of cooked rice were investigated. The proximate compositions except moisture content of rice decreased as the storage period increased. Water binding capacity, solubility and swelling power of rice flour decreased with the extended storage period. In the amylogram, the initial pasting temperature, paste viscosity and breakdown of paddy rice flour slurry decreased after 2 years of storage. Moisture content of cooked rice increased while the amount of water evaporated during cooking decreased. These trends were obvious with the longer storage period. Lightness and yellowness of cooked rice were greatly changed after 3 years of storage, regardless of storage form. Texture profile analysis of cooked rice by Texture Analyzer revealed that hardness, fracturability, gumminess were gradually increased while adhesiveness decreased as the storage period of rice increased. A trained panel found that color intensity, intactness of grains, rancid flavor, rice bran flavor, wet cardboard flavor, hardness and chewiness of cooked rice increased with the longer storage period. However, glossiness, transparency, plumpness, puffed corn flavor, dairy flavor, boiled egg white flavor, sweet taste, adhesiveness to lips, smoothness and inner moisture decreased with the extended storage period up to 3 years. Instrumental hardness was highly correlated with sensory hardness.

• Culinary science and hospitality research
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• v.17 no.1
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• pp.248-258
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• 2011

To analyze die quality characteristics of loaf bread added with waxy black rice flour by its storage period, this study stored loaf bread made of wheat flour added with 10% 20% 30% and 40% of waxy black rice flour for 4 days while measuring water activity, pH, chromaticity and texture. The results of die study are as follows. Based on die results of measurements of water activity of loaf bread added with waxy black rice flour by storage period, die control group and die groups added with 10% and 20% of waxy black rice flour showed significantly low water activity from the $3_{rd}$ day of storage and die groups added with 30% and 40% of waxy black rice flour from the $2_{nd}$ day of storage. As for pH changes over the storage period, only die group added with 40% of waxy black rice flour showed significant pH decreases from die $3_{rd}$ day of storage while the control group and the groups added with 10% and 30% of waxy black rice flour showed significant pH decreases from die $2_{nd}$day of storage. As for the pH of each group of loaf bread by storage days, die loaf bread added with 40% of waxy black rice flour showed significantly higher pH compared to the control group. Brightness decreased significantly from the 2nd day of storage and die yellowness from the $3_{rd}$ day of storage. As for chromaticity changes by storage days, as die amount of added waxy black rice flour increased, L values and b values decreased while redness values significantly increased. Over die storage period, hardness, gumminess and chewiness increased and die waxy black rice flour added groups showed lower increase rates compared to die control group. Especially, die groups added with 30% and 40% of waxy black rice flour showed low hardness changes. Springiness level was decreased as die addition rate of waxy black rice flour was increased, and the group added with 40% of waxy balck rice flour showed die lowest springiness level. It also showed lower cohesiveness up to the 3rd day of storage compared to die day of manufacturing. Therefore, it could be seen that die loaf bread made from wheat flour added with 30% of waxy black rice flour showed better quality feature until die $3_{rd}$ day of storage than die other experimental groups.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.1
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• pp.94-102
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• 2007

This study was designed to characterize the physicochemical effects of the addition of rice wine cake(0, 1, 2, 4%) to yackwa. Dietary fiber, volume, SEM, TBA, color, texture characteristics and sensory evaluation of yackwa were investigated. The dietary fiber content of rice wine cake was 10.24%, and the dietary fiber content of yackwa increased with added rice wine cake. The extensibility value increased with more rice wine cake. SEM revealed, many holes in a delicate structure with many layers. During a 4-week storage period, yackwa containing rice wine cake had lower TBA values than control, except for the sample containing 4% rice wine cake. The TBA value of yackwa containing 4% rice wine cake had the highest TBA value. The L value and b value of samples decreased with the addition of rice wine cake and storage time, but the value increased with added rice wine cake according to the storage time. The hardness, cohesiveness and gumminess of yackwa increased according to the time of storage and the addition of rice wine cake, but the springiness and chewiness of yackwa decreased. In sensory evaluations, all items received the lower scores according to the storage time. Yackwa that contained 1%(RWC1) received the highest score for color and flavor, and yackwa that contained 2% (RWC2) had the highest score for crispness and roast. Overall preference was, in order: RWC2 > RWC1 > CON > RWC4. Yackwa that contained $1{\sim}2%$ rice wine cake possessed superior features in most of the quality properties and in sensory evaluation, so yackwa that contains rice wine cake can be used as a functional food.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.92-100
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• 2014

In this study, the physicochemical and sensory properties of glutinous rice kochujang added with germinated barley powder were periodically examined during storage at $20^{\circ}C$ for 40 days. The pH level of glutinous rice kochujang added with germinated barley powder increased gradually with a higher amount of germinated barley powder, whereas it gradually decreased during storage. On the other hand, acidity showed the opposite pattern. The salinity of samples decreased gradually with a higher amount of germinated barley powder. The L-, a and b-values of samples increased gradually with a higher amount of germinated barley powder, whereas they decreased gradually during storage. Amino nitrogen content of glutinouse rice kochujang increased gradually with a higher amount of germinated barley powder, whereas they increased gradually during storage. In the sensory evaluation, glutinous rice kochujang added with 5~10% germinated barley powder was superior in color, texture and overall preference. Therefore, addition of 5~10% germinated barley powder was optimum for improving kochujang quality.

• Mycobiology
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• v.35 no.1
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• pp.36-38
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• 2007

Stored rice was collected from rice processing complexes of National Agricultural Cooperative Federation of 11 regions in Korea to evaluate the occurrence of fungi and bacteria and to identify the predominant fungi and bacteria to the genus levels. Most rice samples generally produced the higher levels of fungi and bacteria than white rice. The occurrence of fungi and bacteria varied in various locations of Korea. Among fungi observed, Aspergillus spp. and Penicillium spp. were dominant in the samples and Aspergillus spp. were observed more frequently than Penicillium spp. Predominant bacteria from rice and white rice samples tentatively belonged to the Genus Bacillus, Pectobacterium, Pantoea, and Microbacterium according to BIOLOG and FAME analyses. The results of this study showed that rice in Korea was contaminated in a relatively high level by two dominant storage fungi such as Aspergillus spp. and Penicillium spp. In addition, occurrence of mycotoxins in rice by the fungi could be possible and thus it is necessary to control the storage fungi.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.225-231
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• 1992

This investigation was undertaken for the purpose of studying me quality, acceptibility and storage of soybean rice cake containing various levels of soybean. Soybean rice cake was stored at 30$^{\circ}C$, room temperature (18~20$^{\circ}C$) and 5~6$^{\circ}C$. Sensory evaluation was done by panels of 7 judges. Objective measurements were made by utilizing me Instron and Hunter Colormeter. The results were as following; 1. By sensory evaluation, 30% soybean of soybean rice cake was better than others during storage periods. 2. By Instron measurement of soybean rice cake, Hardness was tend to increase as addition level of soybean decreased and as storage periods increased. Hardness had significant relationship with consistency, moistness and texture during storage at 5~6$^{\circ}C$. 3. By color value of soybean rice cake, b value was tend to increase as me addition level of soybean increased and decrease as storage periods increased. The Hunter of L,a,b showed mat color of sensory evluation had significant relationship with only b value.

• Food Science and Preservation
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• v.13 no.6
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• pp.675-680
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• 2006

Uniform milling is regarded as a very essential technology to produce high quality milled rice in Rice Recessing Complex. But non-uniformly milled rice can be produced very easily because of unadequate operation methods of milling system and bad brown rice conditions. This study was conducted to find out the bad effect of non-uniform milling degrees and store temperatures on quality characteristics such as taste of cooked rice, fatty acidity, whiteness and so on of milled rice during storage. According to the increase of non-uniform milling degrees, the fatty acid acidity and b value were increased very rapidly, and taste of cooked rice and whiteness were decreased very rapidly during storage. And the general quality characteristics of milled rice were better at low temperature storage of $5^{\circ}C$ than at high temperature storage at $25^{\circ}C$.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.262-262
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• 2017

Brown rice contains a variety of nutritional and bio-functional components compared to milled rice. However, low consumer preference for steamed brown rice and short shelf life has been implicated as deterrents to the direct consumption of brown rice. This study was undertaken to determine the effect of degree of milling (DOM) on pasting and aging properties of brown rice cultivar. Short-grain (Japonica type) brown rice cv. Boseogchal (BSC), Baegjinju (BJJ), and Hiami (HIAM) were evaluated every month during 4 months storage. Rice cultivar were categorized into waxy (BSC), medium-waxy (BJJ), and non-waxy (HIAM) of which amylose contents were 6.81%, 10.06%, and 16.69~16.72%, respectively. Peak viscosity was the highest in BJJ followed by HIAM, and BSC, showing peak viscosity was lower at low temperature storage. At storage at room temperature from 60 to 120 days, the FFA content significantly increased in the rice samples with DOM1% followed by 3% and 5%, while not significant increase in DOM0% brown rice: at 120 days, the FFA ranged in 28.35~41.48, 111.99~130.06, 76.87~91.99, and 47.13~62.37 mg KOH/100g for DOM 0%, 1%, 3% and 5%, respectively. It indicated that the fat rancidity was the least in the order of DOM 0%, 5%, 3% and 1%. Storage at low temperature could reduce fat hydrolysis with lower FFA release, but rice grain with 1% MD also released more FFA compared to the other samples. It could be assumed that the most outer bran layer, approximately 1~3%, could provide a strong protection from fat rancidity. Pasting viscosity of rice samples also increased with increasing DOM rate. Results indicated that DOM was the most significant factor for lipid rancidity during storage, resulting in high FFA formation. It suggested that brown rice with DOM 0% and/or more than DOM 5% could provide the best shelf life.