• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.228-233
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• 2008

This study was carried out to get the genetic information on the germination rate and fat acidity after 12 weeks' storage at $35^{\circ}C$. Germination rate decreased with longer storage period, while fat acidity increased. Germination rate was higher in the order of Koshihikari, Hanmaeum and Unkwangbyeo after 12 weeks' storage at $35^{\circ}C$. Fat acidity of Koshihikari and Hanmaeum was gradually increased, but that of Unkwangbyeo was dramatically increased after 4 weeks' storage at $35^{\circ}C$. The genetic mode on germination rate and fat acidity using the joint scaling test was shown to be additive-dominance gene effects. Additive([d]) effect was higher than dominance effect([h]) in all crosses. The average degree of dominance, [h]/[d], was less than 1, indicating that germination rate and fat acidity was partially dominant. Germination rate and fat acidity based on frequency distribution of 2 crosses were quantitative characters expressed by polygenes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.29-35
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• 2007

This study was conducted to investigate the germination rate, fat acidity and lipoxygenase activity of brown rice after storage of 6 and 12 weeks at high temperature ($35^{\circ}C$) with fifteen Korean and two Japanese rice varieties. Germination rate in rough rice and palatability value in cooked rice by rice taster were lower with longer storage period, while protein content, fat acidity, and lipoxygenase activity in brown rice were higher with longer storage period. Fat acidify was negatively correlated with germination rate. However fat acidity was positively correlated with lipoxygenase activity. Seventeen varieties were classified into two groups on the basis of germination rate, fat acidity and lipoxygenase activity after 12 weeks' storage at high temperature; Group I including eleven varieties of Odaebyeo, Sangmibyeo, Unkwangbyeo, Ilpumbyeo, Nampyeongbyeo, Ilmibyeo, Donganbyeo, Jungsanbyeo, Koshihikari, Hitomebore and Chucheongbyeo showed high germination rate, low fat acidity and low lipoxygenase activity, while Group II including six varieties of Sindongjinbyeo, Hoanbyeo, Gyehwabyeo, Daeyabyeo, Hopyeongbyeo, and Dongin 1 showed lower germination rate, high fat acidity and high lipoxygenase activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.613-617
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• 2011

This study was conducted to compare the quality of the brown rice (BR) and milled rice (MR) during storage. To assess quality, BR and MR were analysed by their fat acidity and flavor pattern using a SMart Nose$^{(R)}$. BR was stored for 30 days at $30^{\circ}C$, and analysed after 5, 15, 20, and 30 days of storage. MR produced in 2005, 2009, and 2010 were also tested. The fat acidity of both rice groups was increased with extended storage and the fat acidity of BR was more rapidly increased than that of MR in general. The flavor patterns from the SMart Nose$^{(R)}$ results were analyzed by the principal component analysis (PCA). The major groups of atomic mass unit (amu) for good discrimination contribution were from 41 to 85 amus. The PCA1 and PCA2 of BR were 95.64% and 2.78%, respectively when the samples were categorized by storage period. The PCA1 and PCA2 of MR were 81.18% and 13.85%, respectively when the samples were compared by production year. Both rice groups could be practically differentiated into flavor patterns by volatile properties for storage period. With regard to the correlation between fat acidity and flavor pattern, we could find that increasing storage period increased fat acidity value and changed flavor pattern from SMart Nose$^{(R)}$. Accordingly, SMart Nose$^{(R)}$ could be successfully used for easy screening and quality evaluation of stored rice.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1091-1095
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• 2009

The aim of this study investigated the fluctuations of 3 characters from 3 ecotypes [early ripening (ER), middle ripening (MR), and late ripening (LR)] of 20 Korean brown rice cultivars in different storage systems [time: 12 and 24 weeks, temperature: low ($10^{\circ}C$) and room ($25^{\circ}C$)]. With increase of storage time and temperature, lipoxygenase activity, and fat acidity increased, whereas germination rate was reduced. ER cultivars exhibited the highest lipoxygenase activity of $35.49{\pm}2.46$ unit/mg protein during 24 weeks storage at $25^{\circ}C$, followed by LR ($32.73{\pm}1.33$) and MR ($32.66{\pm}1.62$) cultivars. The amounts of fat acidity also were observed by the same order (ER: $20.40{\pm}2.12$>LR: $19.68{\pm}1.86$>MR: $19.64{\pm}1.35$ mg KOH/100 g). Germination rate slightly decreased with increase of time and temperature (MR>LR>ER), but MR and LR cultivars showed the most significant changes (ER: $60.90{\pm}23.47%$, MR: $32.66{\pm}13.95%$, and LR: $32.53{\pm}5.87%$). On the basis of above results, MR cultivars were evaluated the highest quality, because high lipoxygenase activity, high fat acidity, and low germination rate have deteriorated in quality and generated off-odor. Thus, MR cultivars might be very important sources in food processing and stored dietary supplement aspects.

• 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.

• Animal Bioscience
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• v.35 no.2
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• pp.281-289
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• 2022

Objective: The aim of this study was to characterize the exopolysaccharides (EPS)-producing lactic acid bacteria from Taiwanese ropy fermented milk (TRFM) for developing a clean label low-fat fermented milk. Methods: Potential isolates from TRFM were selected based on the Gram staining test and observation of turbid suspension in the culture broth. Random amplified polymorphic DNA-polymerase chain reaction, 16S rRNA gene sequencing, and API CHL 50 test were used for strain identification. After evaluation of EPS concentration, target strains were introduced to low-fat milk fermentation for 24 h. Fermentation characters were checked: pH value, acidity, viable count, syneresis, and viscosity. Sensory evaluation of fermented products was carried out by 30 volunteers, while the storage test was performed for 21 days at 4℃. Results: Two EPS-producing strains (APL15 and APL16) were isolated from TRFM and identified as Lactococcus (Lc.) lactis subsp. cremoris. Their EPS concentrations in glucose and lactose media were higher than other published strains of Lc. lactis subsp. cremoris. Low-fat fermented milk separately prepared with APL15 and APL16 reached pH 4.3 and acidity 0.8% with a viable count of 9 log colony-forming units/mL. The physical properties of both products were superior to the control yogurt, showing significant improvements in syneresis and viscosity (p<0.05). Our low-fat products had appropriate sensory scores in appearance and texture according to sensory evaluation. Although decreasing viable cells of strains during the 21-day storage test, low-fat fermented milk made by APL15 exhibited stable physicochemical properties, including pH value, acidity, syneresis and sufficient viable cells throughout the storage period. Conclusion: This study demonstrated that Lc. lactis subsp. cremoris APL15 isolated from TRFM had good fermentation abilities to produce low-fat fermented milk. These data indicate that EPS-producing lactic acid bacteria have great potential to act as natural food stabilizers for low-fat fermented milk.

• Korean Journal of Food Science and Technology
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• v.2 no.1
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• pp.104-112
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• 1970

Korean Paldal variety rice, harvested November and hulled into polished and unpolished forms in April, 1969, packed in the straw bags and the kraft paper bags. Being irradiated with 10, 30 and 50 krad ${\gamma}-ray$, the samples were stored at room temperature for testing infestation, uric acid content, fat acidity, riboflavin content and panel test. The results are as follows. 1. The kraft bag lot with polished rice or unpolished rice manifested the apparent disinfestation with $30{\sim}50$ krad irradiation. On the other hand, in the straw bag lot the irradiation effects on disinfestation were weakened through summer on account of the second contamination. 2. The changes of uric acid content in rice were proportional to the state of infestation. 3. Fat acidity, which has a close relation with the rancidity of fat in rice, increased during storage and showed some increasing tendency in the irradiated lot with $30{\sim}50$ krad. 4. In comparison with the control lot, riboflavin content was not affected by 50 krad irradiation. 5. With 10, 30 and 50 krad dose, the irradiated lot should have no significant difference in taste, odour, color and viscosity for the panel test.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.1032-1038
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• 2008

This study was conducted to develope carbohydrate-based fat replacement for use in the preparation of non-(trans) fatty acid and low-caloric bread. Characteristics such as leavening height of batter, pH, titratable acidity, specific volume, sensory evaluation, shelf life and texture change of bread made using 11 types of carbohydrate-based fat replacements were measured. The 11 carbohydrate-based fat replacers (No. $1{\sim}11$) were prepared using maltodextrin as a base, and different ratios of calcium sulfate, ascorbic acid, sodium stearoyl lactylate and methyl cellulose. The pH was lowered and the total titratable acidity was increased after four hours of fermentation in the control and the samples of dough that contained the fat replacement. In addition, the leavening height of the control was 5.0cm (maximum) after two hours of fermentation and 4.6 cm after four hours of fermentation, which was similar to the heights observed when No.$9{\sim}11$ were evaluated. When the specific volume of the bread was evaluated, the 3% of fat replacement No. 10 produced the best results. When taste was evaluated, there was no significant difference between the control and the bread produced using 1% No. 10, however, there was a significant difference between the control and all samples that contained 2% or more of the fat replacement. Furthermore, the addition of a greater concentration of the fat replacer resulted in a greater moisture. However, there were no significant differences in the color of the control and any of the samples. Additionally, measurement of the firmness of the bread during four days of storage at $25^{\circ}C$ revealed that it decreased as the concentration of fat replacer increased. In addition, the sample that contained 3% of sample No. 10 showed a firmness of 18kgf after three days of storage, while the control showed a firmness of 18kg after two days, which indicates that the degradation of the bread that contained the fat replacer was delayed by one day. The bread made using fat replacers was found to have a better taste, flavor, color, texture and firmness than the control, and the best results were observed in response to the addition of 3% of replacement No. 10. The results of this study will be useful in the production of non-(trans) fatty acid, low caloric bread.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1398-1403
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• 2009

Present study deals with variations of physicochemicals including $\gamma$-aminobutyric acid (GABA), $\gamma$-oryzanol, free sugar, lipoxygenase activity, fat acidity, and germination rate from Korean brown rice cultivars. With increase of storage time and temperature, GABA, $\gamma$-oryzanol, lipoxygenase activity, and fat acidity increased, whereas free sugar and germination rate was reduced. Among cultivars, 'Gopumbyeo' exhibited the highest contents in GABA and $\gamma$-oryzanol during 12 weeks storage at $25^{\circ}C$ (GABA: $28.6{\pm}5.6{\rightarrow}170.4{\pm}4.6\;mg/100\;g$, $\gamma$-oryzanol: $6.1{\pm}0.7{\rightarrow}6.7{\pm}0.4\;mg/g$) and 'Ilpumbyeo' significantly decreased in free sugar during 12 weeks storage at $10^{\circ}C$ ($1,423.7{\rightarrow}1,058.4\;mg/100\;g$). Moreover, 'Taebongbyeo' exhibited the highest quality owing to low lipoxygenase activity, low fat acidity, and high germination rate. In free sugar compositions, sucrose exhibited the highest content (>70%), followed by fructose (>7%), raffinose (>5%), glucose (>3%), and maltose (>2%) during storage. Based on our results, changes of physicochemicals in stored brown rice may be important information in processing food and functional properties.

• Korean Journal of Food Science and Technology
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• v.3 no.1
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• pp.19-24
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• 1971

The Korean rice, Nonglim # 6 was milled into brown rice and 92% polished one and packed with the kraft paper bags. The sample, bags were irradiated with the respective doses of 30, 50, 600 and 800 Krad and then were stored at $10^{\circ}C$ and 75% RH. Changes of fat acidity, amylase activity, viscosity of thus irradiated rice were examined during storage. The results were as follows. 1) Fat acidity increased slightly in the range of $30{\sim}50$ Krad but remarkably in the range of $600{\sim}800$ Krad. However, the rate of increase was low in comparison with the storage under the room temperature. 2) The amylase activity of both the low dose lot and the control decreased in the same rate during the storage. However the high dose lot had more remarkable decrease of the amylase activity from the beginning. 3) The viscosity by Brabender amylogram showed the slightly decreasing tendency in both the low $30{\sim}50$ Krad lot and the control lot of the polished rice powder during storage. On the other hand, the high dose lot of 600 or 800 Krad marked the similar decreasing rate but by far the lower values of the viscosity. 4) The results of the organoleptic test presented no differences between the low dose lot and the control lot, but the high dose lot and the control lot differed significantly only in the color.