• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.66-71
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• 1996

To extend shelf life of cooked rice, main putrefactive microorganism isolated from cooked rice were identified by using the API 50 CHB kit and fatty acid analysis of the cell and antimicrobial activity of water extract of green tea was tested against isolated strains and some type of strains. The growths of Bacillus subtilis ATCC 6633, Salmonella typhimurium ATCC 14028, Bacillus cereus YUFE 2004 and Staphylococcus aureus YUFE 2087 were inhibited in broth containing 500 and 1000 ppm of green tea extract. Main putrefactive microorganisms of cooked rice were identified as Bacillus subtilis RHJ-I and Bacillus subtilis RHJ-II. Green tea extract of 500 and 1000 ppm level inhibited the growth of Bacillus subtilis RHJ-I only.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.1
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• pp.15-26
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• 1994

To understand the relative contribution of varietal and environmental variation on various grain quality components in rice, grain appearance, milling recovery, several physicochemical properties of rice grain and texture or palatability of cooked rice for milled rice materials of seven cultivars(five japonica & two Tongil-type), produced at six locations of the middle and southern plain area of Korea in 1989, were evaluated and analyzed the obtained data. Highly significant varietal variations were detected in all grain quality components of the rice materials and marked locational variations with about 14-54% portion of total variation were recognized in grain appearance, milling recovery, alkali digestibility, protein content, K /Mg ratio, gelatinization temperature, breakdown and setback viscosities. Variations of variety x location interaction were especially large in overall palatability score of cooked rice and consistency or set- back viscosities of amylograph. Tongil-type cultivars showed poor marketing quality, lower milling recovery, slightly lower alkali digestibility and amylose content, a little higher protein content and K /Mg ratio, relatively higher peak, breakdown and consistency viscosities, significantly lower setback viscosity, and more undesirable palatability of cooked rice compared with japonica rices. The japonica rice varieties possessing good palatability of cooked rice were slightly low in protein content and a little high in K /Mg ratio and stickiness /hardness ratio of cooked rice. Rice 1000-kernel weight was significantly heavier in rice materials produced in Iri lowland compared with other locations. Milling recovery from rough to brown rice and ripening quality were lowest in Milyang late-planted rice while highest in Iri lowland and Gyehwa reclaimed-land rice. Amylose content of milled rice was about 1% lower in Gyehwa rice compared with other locations. Protein content of polished rice was about 1% lower in rice materials of middle plain area than those of southern plain regions. K/Mg ratio of milled rice was lowest in Iri rice while highest in Milyang rice. Alkali digestibility was highest in Milyang rice while lowest in Honam plain rice, but the temperature of gelatinization initiation of rice flour in amylograph was lowest in Suwon and Iri rices while highest in Milyang rice. Breakdown viscosity was lowest in Milyang rice and next lower in Ichon lowland rice while highest in Gyehwa and Iri rices, and setback viscosity was the contrary tendency. The stickiness/hardness ratio of cooked rice was slightly lower in southern-plain rices than in middle-plain ones, and the palatability of cooked rice was best in Namyang reclaimed-land rice and next better with the order of Suwon$\geq$Iri$\geq$Ichon$\geq$Gyehwa$\geq$Milyang rices. The rice materials can be classified genotypically into two ecotypes of japonica and Tongil-type rice groups, and environmentally into three regions of Milyang, middle and Honam lowland by the distribution on the plane of 1st and 2nd principal components contracted from eleven grain quality properties closely associated with palatability of cooked rice by principal component analysis.

• Korean journal of food and cookery science
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• v.7 no.2
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• pp.7-18
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• 1991

This study was experimented saccharification process added malt extract solution into cooked sweet potato and potato with time, temperature and was tested reducing sugar changes, structural changes, pH and sensory evaluation about cooked shik-hae of rice, glutinous rice, potato, sweet potato. The results are summarized as follows: 1. Enzyme activity was highest in malt after four days of barley germination at a room temperature. 2. Electronmicroscopic observation indicated that raw starch granule of potato and that of sweet potato was 25-60$\mu\textrm{m}$ and 8~18$\mu\textrm{m}$ in size, respectively and its shape is oval and globular for potato and sweet potato respectively. 3. Reducing sugars were 1,682.6mg and 1,695.6mg in rice and glutinous rice, respectively, for 6-hour-saccharification at $50^{\circ}C$. Reducing sugars were 1,689.1mg and 1,497.8mg in sweet potato, potato, respectively, for 6.hour-saccharification at $60^{\circ}C$. 4. pH variation during saccharification for sweet potato and potato was pH 5.8~5.4. 5. Sensory evalution showed that there were more significant differences in sweety odor, roasted nutty taste and sweety taste of sweet potato among four samples than the other's color shininess.

• 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 food and cookery science
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• v.28 no.5
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• pp.549-557
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• 2012

In this study, the FFQ-50 questionnaire which composed of 50 food items frequently eaten as sources of dietary fiber, was developed and used to estimate the dietary fiber intake of middle school students in the Chungbuk province. According to the survey, the average daily intakes of dietary fiber for the boys and girls were $23.3{\pm}12.3$ g (93.2%) and $20.8{\pm}11.5$ g (104.0%), respectively, showing a significant difference between the gender. The proportions of boys and girls who did not reach to the sufficient dietary fiber intake were 66.2% and 53.9% respectively. The major sources of dietary fiber were grain foods and vegetables, which measured at 77.24%, followed by fruits, seaweeds, tofu and tofu products, potato and starch, and mushrooms. The cooked white rice contributed the highest (17.81%), followed by baechu-kimchi, cooked brown rice, ramyeon (instant noodle), tangerine, sesame leaf jangajji (pickled sesame leaf), topokki (spicy rice cake stir-fry), blanched and seasoned bean sprouts, bread, and radish kimchi. The study showed that the cooked white rice was the major source of dietary fiber in the boys' diet followed by baechu-kimchi, ramyeon, cooked brown rice, tangerine, bread, strawberry, blanched and seasoned bean sprouts, sesame leaf jangajji, radish kimchi. Girls were taking in dietary fiber mostly from boiled white rice followed by baechu-kimchi, boiled brown rice, tangerine, ramyeon, sesame leaf jangajji, topokki, blanched and seasoned bean sprouts, radish kimchi, and boiled barley.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.422-424
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• 1995

In order to investigate the textural changes of cooked rice in a home electrical rice cooker during warm keeping period, rice was cooked and stored at $73^{\circ}C$ for 42 hours. The time course changes of hardness and adhesiveness of cooked rice were measured with the specimen prepared as a cylindrical rice block(H/D= 15 mm/20 mm). At the initial stage of warm keeping period the hardness was 1.61 kg and it was increased steadily to 1.95 kg up to 12 hours. And it was rapidly dropped to 1.57 kg within 3 hours, and thereafter gradually decreased to 1.44 kg. The adhesiveness was steadily declined with warm keeping period from 0.51 to 0.323kg set The cohesiveness and chewiness were also changed in the similar pattern to that of hardness while the springiness remained unchanged throughout the whole warm keeping period.

• Journal of the Korean Dietetic Association
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• v.11 no.3
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• pp.353-364
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• 2005

The informations concerning knowledge, value and consumption pattern for rice foods of elementary schoolchildren (630 boys and 550 girls in 5th or 6th grade) were investigated in Changwon and Gimhae of Gyeongnam province. They were asked based on knowledge, one’s value and intake frequence of rice foods by questionnaries. Menus for 3 days including 2 weekdays and 1 weekend day were taken from 136 students (77 boys and 59 girls) in two Elementary Schools in Changwon and Gimhae to know intake reality of rice product. The purpose of this survey was to find the way of encouraging rice intake and preference which now seemed to be low because of simplified, westernized eating habits, and to provide basic information needed for inheriting and improving our traditional cooked rice centered eating culture. The results are summarized as follows. The knowledge of rice was positively correlated to the one’s value (r=0.365, p<0.001) and the preference (r=0.132, p<0.001), the one’s value was positively correlated to preference (r=0.409, p<0.001). The score of knowledge for rice was 12.8 points out of 20, the girls get points(13.12) significantly higher than the boys (12.53) (p<0.01). One's value about rice foods was 37.35 points out of 50 what is relatively high. They have eaten cooked rice type food for 2.24 times per day. Both boys and girls in Changwon and Gimhae area were having cooked rice type food significantly more during weekdays compared to weekends (p<0.001) by 3 days food record. According the results, we can see the possibility that schoolchildren can be encouraged to eat more rice foods by nutritional education to go with the development of various programs.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.4
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• pp.514-519
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• 2011

Takju was manufactured using 150 g Rosa rugosa Thunb. (Haedanghwa) and two different preparations of 3,000 g each of cooked and uncooked rice. Nuruk (150 g) and yeast (60 g) were inoculated into both mixtures for fermentation, and physiochemical changes were investigated during 14 days of fermentation. The final brix value, pH, and ethanol concentration of Haedanghwa (uncooked rice Takju) were $13.0^{\circ}$Bx, 4.3, and 11.8%, respectively, whereas those of Haedanghwa (cooked rice Takju) were $14.0^{\circ}$Bx, 4.6, and 14.4%, respectively. Lactic and acetic acid levels in Haedanghwa (uncooked rice Takju) were significantly higher than those in Haedanghwa (cooked rice Takju) (p<0.05). The level of ${\gamma}$-amino-n-butyric acid in Haedanghwa Takju (uncooked rice) was twice than that of Haedanghwa Takju (cooked rice). Our results demonstrate that the use of uncooked rice in the preparation of Takju may help improve the taste and function of the final product.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.613-618
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• 1989

Tirteen rice varieties of Japonica-Indica briefing type (J-I breeding type) and ten of Japonica type produced in Korea in 1985 were studied on cooking quality of milled rice and texture of cooked rice. The results are as follows: in the Looking quality, water uptake ratio of cooked rice and total solid in residual liquid showed significant $(p<2.172^*\;and\;2.419^*,\;respectively)$ between J-I breeding type and Japonica type The water uptake ratio of cooked rice was higher J-I breeding type than Japonica type but the total solid and intensity of iodine blue value in residual liquid were lower J-I breeding type than Japonica type. Minimum cooking time of milled rice showed significant $(p<2.375^*)$ between J-I breeding type and Japonica type for texture of cooked rice. The cooking time of J-I breeding type shorter than Japonica type. Hardness and cohesiveness in texture of cooked rice appeared to be significant cant $(p<4.370^{***}\;and\;2.371^*,\;respectively)$ between J-I breeding type and Japonica type, and then hardness was higher Japonica type than J-I breeding type, but cohesiveness was lower Japonica type than J-I breeding type. The correlation coefficients between amylose content and adhesiveness of varieties in the same type was $-0.922^{**}$ in J-I breeding type and $-0.915^**}$ in Japonica type. The correlation coefficients between protein content and hardness of the varieties in the same type was $0.954^{**}$ in Japonica type and so denoted as positive correlation. And the scatter diagram between protein and hardness could be divided into J-I breeding type and Japonica type.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.653-667
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• 2018

This study evaluated the quality characteristics, the presence of polyphenolic compounds, and radical scavenging activity of rice cooked along with various mixed grains (barley, black soybean, adzuki beans, foxtail millet, proso millet, sorghum, glutinous rice) by following two different cooking methods (normal and pressure cooker). The amylogram and water characteristics of mixed grains showed significant differences based on the presence of different types of mixed grains. The chromaticity, palatability characteristics, presence of phenol compounds, and radical scavenging activity of rice cooked along with different mixed grains showed significant differences according to the nature of mixed grains. Total polyphenol contents of before cooking, cooked-rice added to mixed grains cooked in the normal cooker and a pressure cooker were 4.46~5.16, 0.58~0.93 and 0.65~0.96 mg GAE/g, and total flavonoid contents were 250.74~548.89, 129.26~207.04 and $127.41{\sim}218.15{\mu}g\;CE/g$, respectively. The DPPH radical scavenging activity of before cooking, cooked-rice added to mixed grains cooked in the normal cooker and a pressure cooker was 79.25~181.61, 22.07~53.64 and 7.51~39.97 mg TE/100 g, and ABTS radical scavenging activity was 203.25~328.24, 47.28~84.94 and 58.27~99.51 mg TE/100 g, respectively. Accordingly, it is necessary to different combinations of mixed grains according to the cooking method at home and grain industry.