• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.2
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• pp.98-105
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• 2018

The sale of brown rice batches composed of rice produced in different years is prohibited in Korea. Thus, new methods for the identification of the year of production are critical for maintaining the distribution of high quality brown rice. Here, we describe the exploitation of an enzyme that can be used to discriminate between freshly harvested and one-year-old brown rice. The degree of enzyme activity was visualized through freshness test with Guaiacol, Oxydol, and p-phenylenediamine reagents. With electronic eye equipment, we selected 29 color codes for identifying new brown rice and old brown rice. The discrimination power of selected color codes showed a minimum of 0.263 to a maximum of 0.922 and an average value of 0.62. The accuracy with which new brown rice and old brown rice could be identified was 100% in principal component analysis (PCA) and discriminant function analysis (DFA). The DFA analysis had greater discriminatory power than did the PCA analysis. A verification test using new brown rice, old brown rice, or a mixture of the two was then performed to validate our method. The accuracy of identification of new and old brown rice was 100% in both cases, whereas mixed brown rice samples were correctly classified at a rate of 96.9%. Additionally, in order to test whether the discriminant constructed in winter can be applied to samples collected in summer, new and old brown rice stored for 8 months were collected and tested. Both new and old brown rice collected in summer were classified as old brown rice and showed 50% identification accuracy. We were able to attribute these observations to changes in enzyme content over time, and therefore we conclude, it will be necessary to develop discriminants that are specific to distinct storage periods in the near future.

• Korean journal of food and cookery science
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• v.30 no.4
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• pp.480-485
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• 2014

Brown rice contains both excellent nutritional value and functional advantages. However, its utilization is limited due to its rough texture and higher concentrations of phytic acid compared to white rice. We made brown rice inoculated with Lactobacillus sakei Wikim001 having phytate activity for 12 h (BRWK-12) and 24 h(BRWK-24) at $30^{\circ}C$ and evaluated the quality characteristics in an attempt to solve these problems. The pH of brown rice inoculated with L. sakei Wikim001 was reduced time dependently. A concentration of phytic acid in brown rice inoculated with L. sakei Wikim001 was decreased as compared normal brown rice (BR). BRWK-24 showed significantly high values in the brightness, redness and yellowness (p<0.05). BRWK-24 received higher scores in texture and overall acceptability than those of BR on the sensory evaluation test. Taken together, it is expected that a treatment of L. sakei Wikim001 in brown rice is useful for the development of new fermented brown rice with reduced phytic acid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.2
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• pp.105-112
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• 2017

The mixing of rice and brown rice produced in different years is banned in Korea by the grain management act. However, there has been no reported method for discriminating the production year of rice. The objective of this study was to develop a method for discriminating the production year of rice and brown rice based on their phospholipids content. One hundred rice samples and 130 brown rice samples produced between 2012 and 2015 were collected. Twelve phosphatidylcholine components were analyzed by liquid chromatography-tandem mass spectrometry. Phosphatidylcholine was used as an internal standard to calculate the peak intensity of the samples. A statistical analysis of the results showed that the centroid distance between the stale and new rice was 4.16 and the classification ratio was 97%. To verify the calculated discriminant, 61 and 40 rice samples were collected. The accuracy of discrimination was 82% by primary verification and 80% by secondary verification. The statistical analysis of brown rice showed that the centroid distance between the stale and new brown rice was 3.14 and the classification ratio was 96%. To verify the calculated discriminant, 10 samples of new rice and 30 samples of stale rice were collected and the accuracy of discrimination was 93%. The accuracy of discrimination for rice stored at room temperature was 57.9-92.1% and that for rice stored at a low temperature was 86.8-94.7%, depending on the storage period. For brown rice, the detection accuracy was 94.7-100% at room temperature and 92.1-100% at a low temperature, depending on the storage period. The accuracy of discrimination for rice was affected by the storage temperature and time, while that for brown rice was more than 92% regardless of the storage conditions. These results suggest that the developed discriminant analysis method could be utilized to determine the production year of rice and brown rice.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.506-514
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• 2023

Reported positive ion fragmentation of phenolic acid derivatives in rice (Oryza sativa L.) were summarized based on the literature. A total of eight phenolic acids (4 derivatives of ferulic acid, 3 derivatives of sinapic acid and p-coumaric acid) were isolated and identified from rice (raw and steamed) using UPLC-DAD-QToF/MS. Results revealed that 6-O-feruloylsurose was the major component with 3'-O-sinapoylsucorse being tentatively identified in Oryza sativa L. for the first time as a new hydroxycinnamoyl derivative in rice grains. In our study, raw brown rice had the highest phenolic acid contents with Samkwang showing higher phenolic acid content than Saeilmi and Sindongjin (12.41 vs. 7.89 and 3.10 mg/100 g dry weight, respectively). Of all varieties, brown rice had higher phenolic acid contents than white rice. These contents decreased considerably when rice was steamed whereas, p-coumaric acid and ferulic acid contents were increased. Additionally, contents of rice (raw and steamed) can be used as a fundamental report for new rice varieties.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.69-76
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• 1999

Acidovorax avenae subsp. avenae is the causal pathogen of several hosts including oats corn foxtail millet wheatgrass sugarcane and rice. The pathogen is a seedborne pathogen of rice and known to occur widely in rice growing countries. The pathogen cause inhibition of germination brown stripe on the leaf curling of the leaf sheath and abnormal elongation of the mesocotyl of irce. Bacterial colonies grow slowly and are convex circular and creamy with tan to brown center. The causal baterium is Gram-negative and rod shape with a single polar flagellum Nonfluorescence poly-$\beta$-hydroxybutyrate accumulation and precipitate formation around the colony on the medium are useful in the differentiation of this bacterium from other subspecies of A. avenae as well as nonfluorescent bacteria pathogenic to rice. This bacterium has belonged to the genus of Psdeudomonas but recently was transferred to the new genus Acidovorax on the basis of bacteriological and molecular biological data. However the difference of biochemical characteristics protein profile of the cell and host range among strains should be more clarified. To develop an effective control strategy for this disease understanding of detailed life cycle of the disease ritical environmental factors affecting disease development on each host and relationship to grain discoloration of rice are prerequisite. Although the affected area has been world-widely reported there is on recent progress on the understanding of the bacteriological and ecological characteristics of the causal bacterium and control means of the disease.

• Korean journal of applied entomology
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• v.15 no.1 s.26
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• pp.39-46
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• 1976

As the technology of rice production in Korea has rapidly developed and progressed over the last few years, many problems in rice production have been solved. But with the introduction of new genetic material, the increased use of pesticides, higher fertilizer rates and closer plantings, new problems are beginning to emerge. The brown plant hopper outbreak in 1975 resulted to a great extent from some of the changes in management practices. Some rice diseases and nutritional problems that have existed in Korea but have not been considered of serious consequence, are now becoming increasingly severe and possibly as limiting as the hopper outbreak in 1975. Other diseases and nutritional problems are completely new and their cause and significance have not yet been adequately defined. In this discussion there is no Intention to state, nor is there evidence to support a statement, that any of these problems are going to be limiting factors in the future production of rice on the Korean peninsula. Rather this is an attempt to bring together some of the current field problems in Korean rice so that they can be discussed and where necessary receive suitable consideration for research and control.

• Korean Journal Plant Pathology
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• v.1 no.1
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• pp.38-43
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• 1985

A bacterial brown stripe disease new to Korea was noted for the first time on rice seedlings grown in the nursery pots and in a field nursery. Artificial hypodermic injection and pricking inoculation with isolates obtained from lesions of naturally infected plants produced symptoms similar to those occurring under natural condition. Among eleven species of ten genera of gramineous plants Echinochloa crusgalli, Digitaria sanguinalis and Setaria viridis were the new hosts for the pathogen. On the basis of bacteriological and biochemical tests of isolates from infected rice seedlings, the causal bacterium is considered to be Pseudomonas avenae Manns.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.662-669
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• 2013

The purpose of this study is to examine consumers increased interest pertaining to the structural elements of the triangular gimbap. Through an investigation of their importance by attribute and the attribute's partial value, the preference of the triangular gimbap was obitained. The survey was conducted with a panel of two hundred and one university students, from January 7, 2013 to January 14, 2013. In order to achieve an optimal production of the triangular gimbap, the survey consists of 8 profiles with an orthogonal design for cross-validity authorization and reliability of the model. The statistical data analyses use SPSS/WIN 20.0 for the conjoint analysis. The results of this study indicate that the triangular gimbap, with 30% brown rice, mixed stuffing, weight of 100 grams, and a price of 800 won was selected. It is an estimation that new customers will be attracted to the triangular gimbap that consists of a variety of rice and stuffing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.173-178
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• 2006

Anthocyanin in blackish purple rice is composed of cyanidin, peonidin, malvidin, pelargonidin and delphinidin flavylium ion and their glucosides, which shows antioxidant activity similar to a-tocoperol. It has been demonstrated that cyanidin-3-glucoside(C3G) of anthocyanin has a high-potency antioxidant activity, and is a prominent in anticancer and antithrombotic activity. In analysis of content of anthocyanin from the genetic source of blackish purple rice, the level of C3G was approximately 80% of total contents of anthocyanins, and showed the highest content in Heugjinjubyeo, of which contains an amount of 500 mg by weight of 100g brown rice in comparison that most of varieties has less than 50mg by weight of 100g brown rice. We found that C3G pigment in blackish purple rice was considerably affected by cultural season, cultivation area, ripening temperature, and weather condition, etc. as well as genetic properties. In cross combination between Heugjinjubyeo and Suwon425, intermediate parent $F_9$ generation which was three times higher or more in C3G content than that of Heugjinjubyeo was bred, of which it contained an amount of 1678 mg by weight of 100g brown rice, and we called it 'C3GHi' Rice. And, we found that the C3GHi rice was more excellent than that of the existing Heugjinjubyeo in anticancer and antithrombotic activity. Methanol extract from Heugjinjubyeo was fractionated by organic solvents in order of n-hexane, $CH_{2}Cl_2$ and n-BuOH, and then oryzafuran, quercetin, vanillic acid and protocatechuic acid and their structures from the n-BuOH fraction were ascertained. Oryzafuran of these compounds was a natural compound found firstly in nature. Quercetin and protocatechuic acid besides new compound oryzafuran showed excellent antioxidant ability to vitamin C. These results suggest that blackish purple rice has very high value as a source of various functional food as well as staple food.

• Journal of the Korean Professional Engineers Association
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• v.10 no.3
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• pp.8-16
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• 1977

The pbjective of this study to clarify the varietal resistance to green leaf-and planthopper and the evaluate the nature of the resistance to the insects in connection with the Antibiosis. this study was investigated the reaction of the varieties to insects with 46 rice varieties including recommended varieties of korea, At seedling stage they were in fested with second of third inster nymphs. the results were as follows. 1. Most of the rice vari eties tested showed highly susceptible reaction to Brown planthopper except Mudgo, KR 108-143- and HR529-41-3-2 as resistance, and Akamoch, Satominori, IR 24 and IR 8 asmoderately suscptible. 2. In the test of varietal resistance to white backed planthopper Mudgo, KR 108-243-1, KR 109-154-2 and HR 529-45-3-2 were resistance, and Suweon 82, Tongil, IR 8 palkeum, Iri 309, Hokwang and Chuhoku #31 were Moderatly susceptible. 3. Most of the varieties tested were observed highly resistance to green leafhopper, but Tongil, Suweon 82, IR 24, Milsung and Chuhoku #31 were Moderatly susceptible. 4. the new bred lines HR 108-243-1 are multiple resistance of Brown planthopper, green leafhopper and white babked planthopper, and some others showed moderatly susceptible as. IR 8: Brown planthopper, white backed planthopper. IR 24: Brown poanthopper, green leafhopper. Tongil: suweon #82, Chukoku #31, whist backed planthopper, Green leafhopper.