• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.265-273
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• 2017

In this study, the effect of nuruk prepared from rice with different degrees of milling on the physicochemical and sensory qualities of yakju after accelerated aging was investigated. The results indicated significant differences, except for Fe and Mn contents, in the qualities of aged yakju prepared using nuruk from rice with different degrees of milling. However, the degree of milling of rice did not influence the quality of yakju, except for amino acidity and pH, which significantly decreased as the degrees of milling increased. In addition, as compared to before aging, brownness ($A_{430}$) and color difference significantly increased after aging in all the treatments. The intensity of off flavor in yakju after aging made from 0% milled rice nuruk was the lowest.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.339-346
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• 2012

The quality characteristics of kochujang added with additives of different ratios of rice-nuruk (at 1:0.7, 1:1.0, 1:1.3) were studied. The kochujang was stored for 8 weeks at $20{\pm}3^{\circ}C$. The brix tended to increase by increasing mixing ratio of rice-nuruk in all treatments. It increased rapidly up to 4 weeks fermentation and then showed a slight change after 6 weeks. The more mixing ratio of rice-nuruk increased, the more salinity of samples decreased. The initial pH value of kochujang was 5.08-5.10., however, the pH value decreased to 4.82-4.83 after an 8 weeks of storage period. The initial acid value was 0.66-0.68 and increased from 0.66-0.68 to 0.87-0.89. It had slight reduction phenomenon in the sixth week. As the aging period passed, chromaticity such as $a^*$- and $b^*$-values decreased gradually except for $L^*$-value. The moisture content of samples decreased gradually by adding rice-nuruk. but increased by passing an aging period. The initial amino nitrogen content of sample was 304-315 mg%. It increased to 399-442 mg% during the aging period. As the aging period passed, the total cell number increased from 6.81 log CFU/mL to 7.01 log CFU/mL in the fourth week and then steadily decreased to 6.66 log CFU/mL in the eight week. Results of sensory evaluation show that, as more rice-nuruk was added, the kochujang received a lower mark. There was no significant difference in flavor in all treatments. Color and sweetness with increasing amounts of rice-nuruk showed the lowest score. Saltiness rice-nuruk at the ratio of 1:1.0 was the highest at 6.22 points. Texture scores decreased with increasing amounts of the rice-nuruk Based on these results, the overall acceptability of the 1:0.7 rice-nuruk treatment which received the highest score is considered excellent.

• Applied Biological Chemistry
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• v.29 no.1
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• pp.16-21
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• 1986

Free sugars of Kochujang which were prepared with different starch sources, i.e., glutinous rice, polished barley, wheat flour and sweet potato, were investigated for three months of aging. Glucose was found in all tested samples during aging period and the content increased with time, particularly higher for glutinous rice while lower for sweet potato. Fructose also was found through aging period, its content increased for a month and decreased later. The data showed higher fructose content in the order of sources of sweet potato, wheat flour, polished barley and glutious rice. Maltose and sucrose were detected only at the beginning of aging period and the content were less than 3.5% for maltose in all of samples and than 0.4% for sucrose with glutinous rice and wheat flour. Trace amount of rhamnose was detected in the Kochujang made from polished barley.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.481-486
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• 1996

This study was compared with conventional kochujang and the preparation of saccharification kochujanf with the utilization of waste cooked rice, rice cake, bread. Saccharification kochuiang tested to estimated the pH, reducing sugar and changes of organic acid conients, sensory evaluation during the aging at 60 days. Moisture content were increased about B-10% nd crude fat contents were decreased about 20-40% during the aging at 60 days. Change of pH value of kochujang reduces gradually from pH 5.0 up to pH 4.7 during the aging. Total reducing sugar contents of saccharification kochujang reached maximum value at 50 days. The Products of organic acids of during aging were acetic acid, lactic acid, malic acid, tartaric acid and citric acid of the chief of source. Sensory evaluation conducted by fifteen students as panelists showed that were at 1% level significant difference 7 samples in color, flavour, apperance.

• Journal of the Korean Dietetic Association
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• v.3 no.1
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• pp.23-29
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• 1997

This study was attempted to investigate changes in physiochemical properties of the preparation of saccharification kochujang with retrogradated cooked rice, bread, rice cake and sensory evaluation during 60days aging. 1. Moisture content in 4 samples were slowly increased and pH of kochujang was slowly decreased during aging. 2. Reducing sugar content were about 1.4~2 times higer than $T_3$ and $T_2$ at 50days of aging. 3. In no significant difference 4 samples, the level of adipic acid, citric acid, malic acid was the most and that of acetic acid, iso-butyric acid, fumaric acid, lactic acid, tartaric acid was smaller. 4. Sensory evaluation conducted by fifteen university students as panelist showed that their were more significant difference among four samples and notable preferance for $T_3$ over $T_0$, $T_1$, $T_2$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.3
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• pp.266-270
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• 1991

Storage in the form of brown or milled rice saves space and cut cost rather than storage of rough rice, the common way of grain storage in Korea. But, brown or milled rice may be more susceptable to grain aging and sensory change than rough rice. Rice stored in government warehouse for 20 months after harvest was hulled into brown or milled rice and packaged with kraft paper bag (paper package), polyprophylen (PP package), and polyethylene (PE package). Then, after those rice packages were stored under room condition for one year, we investigated germinability, fat acidity, and sensory change to determine milling and packaging effects. Germinability of rough and brown rice was decreased significantly after long-term storge. In germination rate, Chucheong cultivar was lower than Milyang #23, brown rice was lower than rough rice, but there was no differences within packaging materials. TTC test which had a significant correlation with germinability can be used as a handy procedure for predicting grain germination. Fat acidity was increased as the order of rough < milled < brown rice in terms of milling, and PP < paper < PE package in terms of packaging materials. Especially, storage of brown rice increased fat acidity above 30 mg KOH, indicating one of characteristics of grain aging. To prevent from high fat acidity it was necessary to store in forms of rough grain with paper or PP packaging and milled rice with paper, or PP, or PE packaging. In sensory test of stored grain, eating quality in brown rice was the worst because of acidification of fatty acid. Also, eating quality of stored grain became worse as fat acidity increased.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.393-400
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• 1989

The amounts of $^{14}CO_2$ evolved during the $^{14}C-bentazon$ aging in soil for 3 and 6 months were 6.1 and 14.8% of the original radioactivity, respectively. The presence of earthworms in soil tended to increase the uptake of $^{14}C-bentazon$ by the roots of rice plants, even if it was not statistically significant. The evolution of $^{14}CO_2$ from $^{14}C-bentazon$ in soil increased in the presence of rice plants and earthworms compared with in the absence of them. The uptake of $^{14}C-bentazon$ residues by rice plants decreased remarkably with increasing the aging period within the limit of 3 months both in the absence and presence of earthworms, but there is not much difference between 3-month-aging and 6-month-aging. Much larger amounts of $^{14}C-labelled$ compounds were translocated to the shoots, compared with the data from a previous investigation using maize plants. The amount of non-extractable bound residue increased remarkably with the aging period up to 3 months. The polarity of the compounds extracted from soil increased with the aging and the growing of rice plants, indicating the formation of some polar metabolites.

• Applied Biological Chemistry
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• v.39 no.2
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• pp.127-133
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• 1996

To industrialize the Korean traditional Kochujang, we investigated the process and changes of chemical components of glutineous rice Kochujang and barley Kochujang, which are our major traditional Kochujangs. We prepared traditional glutineous rice Kochujang and barley one in Sunchang and Keosan, respectively. To establish the optimal aging time, we investigated changes of the chemical components and sensory evaluation of the Kochujang during fermentation of 180 days. Changes of chemical components of glutineous rice Kochujang were similar to those of barley Kochujang. The results of sensory evaluation on color, flavor, taste, texture and overall acceptibility indicated that glutineous rice Kochujang was preferred to barley one, and the highest score was obtained at the aging of $90{\sim}120$ days for both Kochujangs. However, we established that the optimal aging time was 150 days by considering changes of permissible chemical components and the results of sensory evaluation at the same time.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.631-637
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• 1999

An investigation was carried out to study the effects of aging time, storage temperature, and drying type on the physical, chemical and sensory properties of Korean rice cake. Water content and cooking properties were significantly influenced by aging time and storage temperature. However, aging time did not affect the soup turbidity. Difference in water content was noticeable by drying type. The microwave treated rice cake (MW) showed a higher water content than the other ones. The lightness (L-value) was not affected by the aging time and drying type. Rice cake storaged at 4oC showed the highest L-value. The textural properties of rice cake were influenced by the all sources of variables. There was a significant difference in hardness between microwave and hot air treated rice cake (MWH), and microwave and vacuum treated rice cake (MWV). In the sensory properties, mean intensities of all attributes except chewiness were significantly different among drying types. The MWV showed a higher acceptability than the MW and the MWH. Scanning electron photomicrographs revealed that the MWV has more porous structure. The MWV was the most desirable one as determined by the physical, chemical and sensory evaluation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.406-412
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• 2014

The influence of rainfall during the ripening stage on pre-harvest sprouting, seed viability, and seed quality was investigated in two Korean rice cultivars, Shindongjin and Hopum. When the rainfall was artificially treated in a greenhouse, HP started to pre-harvest sprouting at three days of rainfall treatment (DRT), but Shindongjin did not show pre-harvest sprouting at 40 DAH treatment and just 0.3~0.8% at 50 DAH, which was much lower than 15.3~25.8% of Hopum in the same treatment. After harvest, the seed germination of Hopum decreased about 10~25% compared to non-treated seeds, but that of Shindongjin decreased much little rate than that of Hopum. The seed longevity tested by accelerated aging decreased with prolonged rainfall period in both cultivars, but the varietal difference was clear; Shindongjin could withstand longer accelerated aging than Hopum. Shindongjin maintained its germination (>50%) ability after 15 days of accelerated aging regardless of the rainfall treatment period and time, but Hopum dropped below 50% germination ability after only 5 days of accelerated aging. In conclusion, rainfall during the ripening stage induced not only pre-harvest sprouting, but also reduced seed quality and longevity during storage, which varied between two cultivars.