• Korean Journal of Organic Agriculture
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• v.18 no.2
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• pp.257-269
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• 2010

To investigate the possibility of discrimination between organic and non-organic rice using stable isotope nitrogen of natural abundance, organic rice of 17 samples and non-organic rice of 13 samples grown at adjoining organic rice field were collected in 2008. Rice was grinded into brown rice, milled rice and hull, and samples were analysed for nitrogen and $\delta^{15}N$ at NICEM. Authors also made inquiries about N source for both farmers who conduct organic- and non-organic rice cultivation. In order to know whether the $\delta^{15}N$ can be used in discrimination between organic and non-organic rice, discriminant analysis were made with SPSS and logistic method. 1. Organic farmers used manure, rice bran, used mushroom culture, fermented fertilizer (company products), and oil cake, but non-organic farmers applied compound fertilizer. Rice straws were remained in organic rice field while moved out in non-organic field. 2. There were difference in $\delta^{15}N$ among organic rice and its byproduct(7.760????% in hull, 6.720????% in rice), but significant difference was not found between them. And the trend was same between province. Non-organic rice showed similar results. 3. Significant difference of $\delta^{15}N$ were found between organic rice and non-organic rice (p<0.01) and between hull of organic rice and that of non-organic rice hull (p<0.05). $\delta^{15}N$ seemed to be useful criteria for discrimination of organic and non-organic rice. 4. When applied discrimination analysis of SPSS and logistic, there were significant difference between organic rice, non-organic rice and its byproducts except brown rice and hull in SPSS method. Hull can be used as the most useful component for unknown sample prediction with 83.3% probability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.573-578
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• 2015

This study was performed to elucidate the fermentation and sensory characteristics of Korean traditional rice wine, makgeolli, made from GABA rice, which has a high content of GABA (gamma-aminobutyric acid). GABA rice is a brown rice that is not easily fermented by general makgeolli manufacturing methods. Thus, the Geupchungju method, which is a Korean traditional manufacturing method for makgeolli using a fermentation starter and additional malt, was considered for making makgeolli from GABA rice. We confirmed that Geupchungju method showed a high saccharification and stable alcohol fermentation ability in the early stages of fermentation. However, malt addition more than 2% resulted in a lower score in the sensory evaluation of the final product. It was also confirmed that GABA content of GABA makgeolli was higher than that of commercial makgeolli by 2.3-fold. Our result provides useful information toward improving quality of brown rice makgeolli.

• Mycobiology
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• v.34 no.1
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• pp.30-33
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• 2006

To screen additives and their mixed ratio suitable for the mycelial growth and fruiting body formation of Oudemansiella radicata in the oak sawdust, additives such as rice bran, fermented soybean powder and wheat bran were used. Generally, the mycelial growth of O. radicata has been stable on oak sawdust mixed with rice bran of $5{\sim}20%$. In case that O. radicata was cultured for about 30 days at $22{\pm}1^{\circ}C$ under the illumination (350 lux) of 12 hours and moisture condition of $90{\pm}5%$, the primordia have been formed gradually from red-brown crusts covering the surface of oak sawdust media. Based on the experimental results from 9 strains of O. radicata, fruiting bodies were produced widely on oak sawdust medium mixed with rice bran of 5 to 30%. Even though fruiting bodies of O. radicata have been produced well on oak sawdust media mixed with rice bran, fruiting bodies of O. radicata were produced intensively on oak sawdust media mixed with rice bran of 10%. Therefore, this result will provide a basic information for commercial production of fruiting body of wild O. radicata. This result is the first report associated with an artificial fruiting body formation of O. radicata in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.339-346
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• 2008

The contents of starch, moisture, crude protein, crude fat, crude fiber, and ash of different varieties of various crops such as brown rice, barley, corn, sweet potato were analyzed. The average starch contents of brown rice, barley, corn, and sweet potato were $70.1{\pm}0.4\;{\sim}\;72.2{\pm}2.1$, $68.7{\pm}0.2\;{\sim}\;71.4{\pm}1.2$, $67.6{\pm}0.8\;{\sim}\;69.4{\pm}1.8$, and $21.7{\pm}0.9\;{\sim}\;28.3{\pm}0.5%$, respectively. The ground powder of each starchy substrate was suspended in distilled water, and then liquefied, saccharified, and fermented by dried active yeast at 32 for 4 days. By statistical analysis, the effectiveness of the contents of the different components such as starch, moisture, crude protein, crude fat, crude fiber, and ash of the crops on the ethanol production were examined. The results showed that the starch content positively affected the ethanol production in all the tested cereals and sweet potato. In brown rice, ash content affected negatively the ethanol production. In barley, protein content affected negatively the ethanol production, while fiber content affected positively the ethanol production. The sweet potato containing higher content of moisture produced less amount of ethanol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1472-1478
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• 2008

Four kinds of wild grape Yakju were fermented with wild grape and cereal such as rice, glutinous rice, barley or millet, and their quality characteristics were investigated. Reducing sugar, total sugar, and activities of $\alpha$- and $\beta$-amylase decreased until 2nd day, increased on 3rd day, and gradually decreased after 5 days of fermentation. Reducing sugar content was in the order of glutinous rice> barley> rice> millet group, and this was consistent with the result of $\beta$-amylase activity. Total sugar content was in the order of glutinous rice> rice> barley> millet group, and it was consistent with starch content of each cereal. Alcohol content decreased after 2 days, then glutinous rice group gradually increased from 3 days whereas other groups showed no difference from 5 days of fermentation. pH decreased until 2 days of fermentation, slightly increased and then showed almost no change after 5 days of fermentation. Total acid increased until 2 days, then decreased on 3rd day of fermentation, and gradually increased in the order of barley> millet> rice> glutinous rice group. L value was the highest in the initial day of fermentation, however it decreased with fermentation time. While a value was also the highest in the initial day of fermentation, it gradually decreased after slightly increasing in 3 days of fermentation. In contrast, b value was the lowest in the initial day of fermentation. It greatly increased until 3 days, then decreased on 5th day of fermentation and gradually increased again. Groups of rice and glutinous rice had more brown color than those of barley and millet. In the sensory evaluation, wild grape Yakju using rice was the most preferred in taste, flavor, and overall preference.

• Journal of Mushroom
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• v.10 no.4
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• pp.236-243
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• 2012

Spent mushroom substrates is composted organic material remaining after a crop of mushroom is harvested. The raw materials of mushroom substrates are same feed ingredient as corncobs, rice brown, wheat brown, cotton seeds and beet pulp. During the mushroom cultivation process, the mushroom substrates was used 15-25% by mushroom and 75-85% of mushroom substrates was remained in the SMS. Among of the spent mushroom substrates, spent mushroom substrates of pleurotus eryngii, Pleurotus ostreatus and Flammuliua velutipes is can be use the energy feedstock of animal feed. The cellulose content of spent mushroom(pleurotus eryngii) substrates containing the sawdust was high and total digestible nutrients (TDN) values was low. The spent mushroom(pleurotus eryngii) substrates fermented with cellulase and xylanase producing bacteria is may be used as an ingredient of feed in TMR for Hanwoo steer.

• Food Science and Preservation
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• v.17 no.5
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• pp.733-740
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• 2010

Brown rice vinegars were prepared by agitated or static acetic acid fermentation using different yeast strains (Saccharomyces kluyveri DJ97, Saccharomyces cerevisiae JK99, Saccharomyces cerevisiae GRJ, or Saccharomyces cerevisiae H9). Organic acid contents and levels of volatile compounds were compared in vinegars prepared by different methods. The chosen yeast strain did not significantly affect the organic acid content of vinegar. In vinegars prepared by agitated acetic acid fermentation, organic acid contents were, in the order of descending abundance, acetic acid, citric acid, lactic acid, oxalic acid, and tartaric acid. In vinegars prepared by static acetic acid fermentation, no citric acid was detected, and lactic acid content was higher than that in agitated acetic acid fermented vinegar. The volatile compounds of both vinegars, analyzed by GC-MS, did not significantly differ when various yeast strains were used. Eighteen volatile compounds were detected in vinegar prepared by agitated acetic acid fermentation and 11 in vinegar prepared by static fermentation. Volatile compounds that can affect vinegar quality, including ethyl acetate and phenethyl acetate, were present at high concentrations in static acetic acid fermented vinegar. Electronic nose analysis showed that volatile chemical patterns differed between the two types of vinegar, but there were no significant differences in sensory scores between vinegars prepared using various yeast strains or by either of the two methods of fermentation.

• Food Science and Preservation
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• v.23 no.6
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• pp.778-787
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• 2016

Fermented vinegars using pear was compared according to the appled side materials. Quality characteristics of three kinds of the fermented vinegars (pear vinegar, PV; pear black rice vinegar, PBV; pear mint vinegar, PMV) were investigated, which includes pH, total acidity, colors, the contents of sugar, amino acids, total polyphenol, and total flavonoid, ${\alpha}^{\prime}{\alpha}-diphenyl-{\beta}-pycrylhydrazyl$ (DPPH) radical scavenging ability, and sensory evaluation. Brown rice vinegar (BRV) was used as a control. The pH and total acidity of the fermented pear vinegars were significantly different showing the range of 3.17~3.43 and 4.01~5.05%, respectively (p<0.05). The sugar contents of PV and PMV were significantly higher than other vinegars (p<0.05). L, a, and b values were the highest in PV, PBV, and PMV, respectively. Among the four vinegars, the essential amino acids were the highest in PV with the order of lysine, isoleucine, valine, and threonine. Besides, the fermented pear vinegars have many non-essential amino acids such as glutamic acid and aspartic acid. The aspartic acid content was the highest in PV while glutamic acid content was the highest in BRV. The total polyphenol content was the highest in PV while total flavonoid content was the highest in PBV. The DPPH radical scavenging ability (%) was the highest in PV. In sensory evaluation, PBV showed the highest color, taste and overall preference scores. These results show that pear would be desirable to prepare high-quality vinegars and functional foods.

• Food Science and Preservation
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• v.23 no.3
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• pp.445-452
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• 2016

In this study, physicochemical properties of acorn flour was investigated, and characteristics of the Jeung-pyun dough added with the acorn flour at various concentrations were evaluated after storage at -$18^{\circ}C$ for 4 weeks and fermentation. Total polyphenolic content, electron donating ability (EDA) of 0.5%, gelatinization onset temperature (To), gelatinization peak temperature (Tp), and gelatinization conclusion temperature (Tc) of acorn flour were 3,525.12 mg%, 16.71%, $68.41^{\circ}C$, $73.83^{\circ}C$, and $82.96^{\circ}C$, respectively. These all values were increased in the Jeung-pyun dough possibly due to addition of the acorn flour. The yeast count was not affected by the addition levels of acorn flour and the frozen storage period before fermentation. The amount of carbon dioxide gas evolved from Jeung-pyun dough during fermentation was significantly changed with the concentration of acorn flour, but it was negligible. The Jeung-pyun added with 6% acorn flour showed an small increase in the amount of carbon dioxide after frozen storage of 1 wk and fermentation. The pH of the fermented Jeung-pyun samples decreased along with the increasing storage period as well as the increasing acorn flour content, ranging from 4.21 to 5.34. Therefore, the frozen Jeung-pyun dough containing 6~15% of acorn flour and stored for 3 weeks was the most desirable among all the tested samples in this study.

• Journal of Radiation Industry
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• v.7 no.1
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• pp.29-35
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• 2013

Microbiological populations and the sterility of commercial powdered products treated with gamma irradiation at 0~10 kGy were investigated before using them as ingredients for a non-cooked Saengsik product. We evaluated a total of 14 powdered products: 8 powdered cereals, 3 powdered tubers, and 3 powdered leafy vegetables. The total numbers of bacterial populations in non-irradiated powdered cereals, tubers, and leafy vegetables were 2.7~6.9, 5.6~6.0, and $5.3{\sim}6.8\;log\; CFU{\cdot}g^{-1}$, respectively. Moreover, coliform bacteria were not indicated in adlay, millet, germinated brown rice, soybean, and mulberry leaves powder within detection limit ($2.0\;log\; CFU{\cdot}g^{-1}$). The number of Bacillus cereus exceeded $3.0\;log\; CFU{\cdot}g^{-1}$ (the maximum limit for Saengsik products) in all samples, excluding perilla seeds, buckwheat, barley, oat, potato, and Jerusalem artichoke powder. However, a dose of 6 kGy of gamma irradiation reduced the microbiological populations in all samples, and all the powdered products met the microbial requirements for Saengsik products. Futhermore, it was confirmed that all microorganisms in the 9 powdered products, except fermented brown rice, sweet potatoes, and 3 leafy vegetables, were sterilized by 10 kGy of gamma irradiation.