• The Plant Pathology Journal
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• v.24 no.1
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• pp.74-79
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• 2008

This research was conducted to evaluate fungal and bacterial populations in unhulled and brown rice under indoor storage conditions, and to examine the relationship between microbial populations and environmental conditions such as temperature and relative humidity. The temperature and relative humidity of the storage room ranged from $22.6^{\circ}C\;to\;27.0^{\circ}C$ and 23.3% to 44.2%, respectively. Total fungal and bacterial populations remained relatively stable over the storage period. Predominant fungi included Aspergillus candidus, A. flavus, A. fumigatus, and Penicillium spp.; the predominant bacteria were Bacillus, Microbacterium, Sphingomonas, and Methylobacterium spp. Total fungi and bacteria were not significantly correlated with either unhulled (r=0.448, P=0.372) or brown (r=0.466, P=0.351) rice. In unhulled rice, total fungi showed positive correlations with total Aspergillus (r=0.994, P<0.001) and total Penicillium (r=0.906, P<0.05); A. flavus was positively correlated with total Aspergillus (r=0.913, P<0.05) and total fungi (r=0.868, P<0.05). In brown rice, Bacillus spp. was also positively correlated with total bacteria (r=0.998, P<0.001). Mean temperature was negatively correlated with A. candidus (r=-0.852, P<0.05) and total fungi (r=-0.961, P<0.01), and mean relative humidity was positively correlated with total Penicillium spp.(r=0.884, P<0.05) in brown rice. Hence these results could provide basic information on the fungal and bacterial populations in unhulled and brown rice stored under room conditions, and on the effect of environmental conditions on the populations of fungi and bacteria, especially Aspergillus and Penicillium spp.

• Journal of Climate Change Research
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• v.3 no.2
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• pp.129-142
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• 2012

This study was carried out to evaluate carbon footprint during unhulled rice production and to compare mitigation technologies of methane, main carbon source during rice production, Carbon footprint of unhulled rice was a sum of $CO_2$ emission of agri-materials manufacture, rice cultivation and waste treatment. It was emitted 1.40 kg $CO_2$ during unhulled rice production, its distribution was 71.1% by $CH_4$ emission of rice cultivation, 11.8% of $N_2O$ emission by nitrogen application and 7.6% of complex fertilizer manufacture. $CH_4$ emission could be mitigated by some technologies; cultivation of the early maturing rice variety emitted lower by 44.4% than the mid maturing variety, intermittent drainage of submerged water by 43.8% than the continuous flooding condition, direct seeding by 32.0% than transplanting cultivation, no-ploughing by 20.9% than ploughing cultivation. It means that LCA on Global Warming Potential and the statistical data on innovated technical practice are key tools to systemize Measurable-Reportable-Verifiable (MRV) system for carbon footprint and carbon emission trade in the farm base.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.121-129
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• 2010

We evaluated microbial populations and aflatoxin production in unhulled and white rice from rice processing complexes of the National Agricultural Cooperative Federation in five regions in Korea and identified three predominant Aspergillus species. Fungal and bacterial populations in rice samples were significantly different between regions in 2007. Aflatoxins were also detected and varied at the levels of 2.45 - 3.43 ng per g unhulled rice grain and 1.29 - 2.09 ng per g white rice grain. Unhulled rice generally detected higher level of aflatoxins than white rice regardless of sampling regions; however, no significant differences were found in Anseong and Cheonan in 2005 and Cheonan and Gimpo in 2007. Aflatoxin production between sampling regions was not different regardless of rice type and sampling year. Although the fungal diversity was highly distinct from region to region, three Aspergillus isolates were predominant in the rice samples; thus, representative isolates AC317, AF57, and AF8 were selected and identified based on their morphological and molecular characteristics. Consequently, isolates AC317, AF57, and AF8 were identified as A. candidus, A. flavus, and A. fumigatus, respectively. These fungi can produce mycotoxins that are harmful for consumers and thus it is important to detect and reduce the population of storage fungi in rice.

• Applied Biological Chemistry
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• v.37 no.2
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• pp.72-76
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• 1994

Effects of rice type (unhulledy, brown, and polished rice), varieties, moisture content, and shape (length and diameter), on rice of puffability by hot air were investigated. The puffability of unhulled rice was the highest among them. In addition, relative crystallinities of puffed paddy by hot air puffer ($55{\pm}5\;sec.$, at $210{\pm}5^{\circ}C$) were lower than those of brown and polished rice. The puffability of Wongbongolchalbyeo, glutinous rice, and Jinjubyeo, non-glutinous rice, was good, respectively. Optimum moisture content of unhulled rice for maximum puffed volume was in the range of $10{\sim}12%$ (w/w).

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.299-305
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• 1978

According to the milling degree (unhulled, brown, 70% polished, and 90% polished rice), cropping areas (Sabong, Myeungsuk, Hadong, and Sanchung), and variety of rices (Yusin and Milyang), the contents of copper, lead, zinc, nickel, mercury, cadmium, chromium, and manganese were analyzed in order to investigate heavy metals in the rice of Kyeong Nam district for two years(1976-1977) by the atomic absorption spectrophotometer. The results obtained were as follows; 1. The contents of heavy metals in all the sample rices observed in this experiment were decreased with the increase of milling degree, but significant difference of the heavy metals was not observed among the cropping areas and variety of rices. 2. The contents of heavy metals were copper, 0.80-2.89 ppm; zinc, 3.23-17.60 ppm; manganese, 6.72-70.25 ppm; and lead, ND-0.64 ppm. 3. The contents of nickel and chromium in unhulled rice were in the range of 2.04-40.64 and 5.09-39.95 ppm, respectively, but these heavy metals were in trace for 90% polished rice. 4. The mercury and cadmium were in trace for some unhulled rice, but they were not detected in polished rice.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.823-833
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• 1996

An ultimate purpose of this study is to develop an automatic brown rice quality inspection system using image processing technique. In this study emphasis was put on developing an algorithm for discriminating the brown rice kernels depending on their external quality with a color image processing system equipped with an adaptor for magnifying the input image and optical fiber for oblique illumination. Primarily , geometrical and optical features of sample images were analyzed with unhulled paddy and various brown rice kernel samples such as sound, cracked, green-transparent , green-opaque, colored, white-opaque and brokens. Secondary, an algorithm for discrimination of the rice kernels in static state was developed on the basis of the geometrical and optical parameters screened by a statistical analysis(STEPWISE and DISCRIM Procedure, SAS ver.6). Brown rice samples could be discriminated by the algorithm developed in this study with an accuracy of 90% to 96% for the sound , cracked, colored, broken and unhulled , about 81% for the green-transparent and the white-opaque and about 75% for the green-opaque, respectively. A total computing time required for classification was about 100 seconds/1000 kernels with the PC 80486-DX2, 66MHz.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.6-14
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• 2008

Objective of this study was to investigate the residual levels of mercury (Hg) in soil for "Top-rice" area and its uptake into rice plant for making sure food safety as compared to "Top-rice" & common rice produced from 2005 to 2006. Hg was analyzed with the direct mercury analyzer (DMA 80, Milestone, Italy), which implements the US/EPA method 7473. The average concentration of Hg in paddy soil was 0.031 mg/kg, which was below at 1/25-1/65 fold of the threshold levels (concern level 4 mg/kg, action level 10 mg/kg) for soil contamination designated by "The Soil Environment Conservation Law" in Korea. The maximum residue level (MRLs) for Hg residue in the polished rice is not designated in Korea. Therefore, Hg contents in the polished rice of "Top-rice" brand and common rice were compared to other country's criteria. Hg contents in the polished rice of "Top-rice" brand was 0.0018 mg/kg, which was lower at 1/10-1/30 fold than the MRLs, 0.02 mg/kg of China criteria and 0.05 mg/kg of Taiwan criteria, respectively. Hg were 0.02788, 0.00896, 0.00182, 0.00189, 0.00166, 0.00452 and 0.00145 mg/kg in soil, rice straw, unhulled rice, rice hulls, brown rice, rice bran, and polished rice produced in 2006 "Top-rice" area, respectively. For the ratio of Hg as compared to Hg contents in soil, there were 0.321 of rice straw ${\gg}$ 0.162 of rice bran ${\gg}$ 0.068 of rice hulls > 0.065 of unhulled rice > 0.060 of brown rice> 0.052 of polished rice. And, the slope of Hg uptakes was steeped as following order; rice straw ${\gg}$ rice bran ${\gg}$ rice hulls > unhulled rice > brown rice > polished rice. It means that the more slope steeped was the more uptakes. For the distribution of Hg uptaken, there was 83.8% into rice straw, and 16.2% into unhulled rice, 2.8% into rice hulls, 12.4% into brown rice, 3.5% into rice bran and 9.7% into polished rice. Consequently, it was appeared that the Hg contamination in the polished rice should not be worried in Korea.

• Journal of Environmental Health Sciences
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• v.20 no.3
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• pp.49-53
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• 1994

To isolate the ochratoxin A producing strains from agricultural products and soil in Youngnam districts, rice (37), unhulled rice (10), barley (20), unhulled barley (3), corn (21), soil (26), meju (25), malt (8), soybean (26) and peanut (15) were collected from homes and markets of Youngnam districts through September 1992 to November 1992. 187 strains of Aspergillus spp. and Penicillium spp. were isolated from 191 samples. As a result of screening by TLC, 36 strains expressed fluorescent spot and a same Rf value of standard ochratoxin A, and 9 strains of them were identified as ochratoxin A producing strains by HPLC.

• Journal of Food Hygiene and Safety
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• v.4 no.3
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• pp.177-184
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• 1989

Contents of inorganic compounds in various cereals (Rice: 62, Barley: 39, Soybean: 58, Unhulled barley: 59) collected from Youngnam Districts in 1989 were determined by the atomic absorption spectophotometer. The results abtained as follows: The ranges of zinc level in rice, barley, soybean and unhulled barley were 46.91-76.28 ppm, 42.24-77.06 ppm, 73.39-103.69 ppm and 48.08-272.49 ppm, and those of manganes in each samples were 4.96-14.75 ppm, 20.62-16.28 ppm, 23.31-42.488 ppm and 23.52-30.15 ppm respectively. The ranges of iron level in rice, barley, soybean and unhulled barley were 65.38-141.33 ppm, 52.22-133.25 ppm, 106.32-240.20 ppm and 66.44-108.64 ppm, and those of calcium in each samples were 10.25-33.67 ppm, 68.94-136.62 ppm, 492.20-967.84 ppm and 75.30-165.85 ppm respectively. Meanwhile, contents of sodium in rice, barley, soybean and unhulled barley were 291.60-453.60 ppm, 462.25-773.60 ppm, 463.83-792.67 ppm and 777.90-950.90 ppm and those of potassium in above samples were 716.00-1180.60 ppm, 1363.60-1686.00 ppm, 2233.84-2792.67 ppm and 2042.10-2141.46 ppm respectively.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.581-585
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• 1992

To isolate zearalenone-producing strains from agricultural products in Youngnam districts, various samples such as rice(60), barley(52), soybean(45), peanut(33), corn(32), maeju(27), unhulled rice(UR, 40), unhulled barley(UB, 54), and soil(32) collected. From 375 samples, 302 Fusarium strains were isolated. The isolated strains were cultured for 14 days at $30^{\circ}C$ in rice medium, and then screened zearalenone-producing strains by TLC and HPLC. The result was that 29 isolates[rice(3), maeju(2), corn(1), barley(5), soil(4), peanut(3), soybean(4), U.B.(5), U.R.(2)] were screened as zearalenone-producing strains by TLC, while 19 isolates [rice(2), maeju(1), corn(1), barley(4), soil(3), soybean(2), U.B.(3), U.R.(3)] by HPLC method.