• Korean journal of food and cookery science
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• v.20 no.4
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• pp.380-386
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• 2004

This study was carried out to investigate the quality characteristics of Jeung-Pyun with respect to the addition ratio of pigmented rice and fermentation method. As the mont of pigmented rice was increased, the moisture content of the products added with yeast tended to increase more than those made in the traditional way. Regardless of fermentation method, L value and b value of Jeung-Pyun without pigmented rice were higher than those of Jeung-Pyun with pigmented rice, for which the values were significantly low. The samples with 5% or 10% pigmented rice had a high degree of expansion. The other samples showed no visible difference. The hardness, cohesiveness, springiness and chewiness tended to decrease. On the other hand, the adhesiveness was increased. In both fermentation methods, as the amount of pigmented rice was increased, the gelatinization degree was raised. In sensory evaluation, the characteristics of Jeung-Pyun with 30% pigmented rice were very poor, except for the characteristics on pore uniformity. The other samples and both fermentation methods were hardly different.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.1
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• pp.55-61
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• 2000

Physicochemical and sensory characteristics of Yukwa(fried rice cookie) made by different processing condition were investigated to estabilish the optimum expansion of Yukwa. The expansion rate and crispness of Yukwa prepared by soaking waxy rice for 24 hours was satisfactory . Addition of 15% soy slurry gave better effect on increasing the expantion rate, crispiness and sensory preference than no addition of soy slurry . Yeast, Soju(distilled liquor) , Mackeali(rice wine, turbid) and Chunju(rice wine, clear) as expansion reagent were added to Yukwa prepration . Yeast and Mackeali among tested expansion reagent showed better expansion rate and lower hardness meausred by texturometer than Chunju. Yukwa added chungju showed more fine structure and lower expantion rate than others. Microwave puffed Yukwa was less expansion rate, but same level of crispiness and hardness compared with oil puffed. And no difference in sensory characteristics such as degree of crispiness and stickiness of microwave puffed and oil puffed.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.21-35
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• 1999

We have previously isolated OsMADS4 gene that is a member of the class B MADS box genes from rice. In this study, another member of the class B MADS box genes was isolated from rice flower by the yeast two-hybrid screening method using OsMADS4 as bait. RNA blot analyses revealed that the clone, OsMADS16, was expressed in the second and third whorls, whereas the OsMADS4 transcripts were present in the second, third, and fourth whorls. These expression patterns of the OsMADS16 and OsMADS4 genes are very similar with those of AP3 and PI, the class B genes of Arabidopsis, respectively. In the yeast two-hybrid system, OsMADS4 interacted only with OsMADS16 among several rice MADS genes investigated, suggesting that OsMADS4 and OsMADS16 function as a heterodimer in specifying sepal and petal identities. We have also isolated OsMADS6 gene using OsMADS1 as a probe. Both are members of the AGL2 MADS family. Various MADS genes that encode for protein-protein interaction partners of the OsMADS6 protein were isolated by the yeast two-hybrid screening method. A majority of these genes belong to the AGL2 family. Sequence Homology, expression pattern, and ectopic expression phenotypes indicated that one of the interaction partners, OsMADS14, appears to be homologous to API, the class A MADS gene of Arabidopsis.

• Microbiology and Biotechnology Letters
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• v.39 no.3
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• pp.274-280
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• 2011

Effects of rice varieties, fermentation temperature, nuruks and yeast on the quality of yakju (Korean traditional rice wine) were investigated. Among various yakju made by using some rice varieties, Chucheong yakju produced the highest ethanol of 18.9%. The maximum amount of ethanol was produced when 2% nuruk and 0.8% yeast were added to cooked Chucheong rice and fermented at $20^{\circ}C$ for 10 days. This Chucheong yakju also showed the best overall acceptability. Changes of physicochemical properties and sensory evaluation of the 3 kinds of Chucheong yakju made by cooked rice and uncooked rice and gruel rice were investigated during fermentation. Ethanol contents of uncooked rice- Chucheong yakju and gruel rice- Chucheong yakju were significantly increased from 10.6% and 9.9% after 3 days fermentation to 17.1% and 17.2% after 7 days fermentation. Sensory evaluation revealed the gruel rice - Chucheong yakju was the best in total acceptability with sweety and refreshing tastes.

• The Korean Journal of Food And Nutrition
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• v.12 no.3
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• pp.219-225
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• 1999

In order to improve the quality of nuruk a Korean traditional fermenting agent for brewing nuruk was modified by a new method inoculating Rhizopus japonicus T2 Aspergillus oryzae L2 and hansenula sp. BC26 which had been isolated from traditional Nuruk. And the characteristics of modified Nuruk were investimgated as compared with current fermenting agents such as commercial Nuruk and rice koji of As-pergillus kawachii. The odor of modified Nuruk was savory but those of commercial Nuruk and rice koji were fetid andinodorous repectively. The extracted waters of modified Nuruk commercial Nuruk and rice koji were yellow pale yellow and colorless and showed 6.15, 6.01 and 3.30 of pH respectively. Mod-ified Nuruk had 7.6${\times}$106CFU/g of yeast but commercial uruk and rice koji had no yeast. Commercial Nuruk had 1.0${\times}$102CFU/g of lactic acid bacteria but modified Nuruk and rice koji had no lactic acid bacteria. The amylolytic and proteolytic activities of modified Nuruk were much higher than those of commercial Nuruk or rice koji. Seed mash of modified Nuruk had ester aroma but that of commercial Nuruk rather offensive odor and that of rice koji neither ester aroma or offensive odor. It seemed that if the modified Nuruk is used in seed mashing the supplement of acidulant is need to lower pH. The quality of modified Nuruk was thought to be much better than that of commercial Nuruk or rice koji.

• Food Engineering Progress
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• v.15 no.3
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• pp.243-249
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• 2011

Optimum conditions to prepare a yeast extract with rice protein hydrolysates(rh) were investigated. The yeast extract was obtained at the level of 2.3 g/L from the yeast culture medium($30^{\circ}C$, 48 hr) composed of 5% rh and glucose( 3%, w/w). Within the extract, RNA was contained at the level of 188.1 mg/g and the levels of GMP and IMP as nucleotides were $650.33{\pm}48{\mu}g/g$, $69{\pm}21{\mu}g/g$, respectively. When Rrh(Residual rice protein hydrolysate by $Delvolase^{(R)}$) was supplemented into a yeast extract, the savory taste like umami of the mixture was found to increase noticeably based on the measurements by taste sensing system as well as sensory test. It is assumed that soluble peptides in Rrh could play an important role in improving the overall taste of yeast extract by enhancing its umami taste. Therefore, the yeast extract supplemented with Rrh could be used for manufacturing a high value-added natural seasoning ingredient.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.568-572
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• 2005

Saccharomyces yeast spores are more resistant to drying and storage than vegetative cells. For the mass production of yeast spores, compressed yeast was directly inoculated into a sporulation medium (SM). The effects of inoculum size and the addition of rice wine cake (RWC) into SM on the sporulation were examined using flasks. With $1\%$ inoculum of compressed yeast, $1.45{\times}10^8/ml$ of asci was obtained. The addition of $0.5\%$ RWC into SM improved the cell growth and spore yield, and the number of asci formed was $2.31{\times}10^8/ml$. The effects of culture temperature, temperature-shift, and concentrations of inoculum, potassium acetate, and RWC on the sporulation were also evaluated using a jar fermentor. The optimum temperature for spore formation was $22^{\circ}C$ where the number of asci formed was $2.46{\times}10^8/ml$. The shift of culture temperature from initial $30^{\circ}C$ for 1 day to $22^{\circ}C$ for 3 days increased the number of asci formed to $2.96{\times}10^8/ml$. The use of $2\%$ (w/v) inoculum of compressed yeast, $2\%$ potassium acetate, and $1\%$ (w/v) RWC in SM with the shift of culture temperature of initial $30^{\circ}C\;to\;22^{\circ}C$ resulted in $90\%$ sporulation ratio and formation of $6.18{\times}10^8\;asci/ml$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.2
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• pp.167-173
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• 2014

Red yeast rice (RYR) is the product of fermented yeast by Monascus strains on rice, and has recently become a popular dietary supplement as a traditional food in Asia. RYR contains monacolin K substances known to inhibit cholesterol synthesis as efficiently as statin drugs. To determine the optimal rice cultivar for manufacturing RYR, 7 rice cultivars (Goami, Goami2, Sangjuchalbyeo, Seolgaeng, Saegyejinmi, Yeonghojinmi and Chilbo) were fermented using two Monascus strains (M. ruber KCTC6122 and KCCM60141 of M. ruber) in this study. The monacolin K content of Sangjuchalbyeo were 47.24 ppm on KCTC6122 cultures and 117.03 ppm on KCCM60141 cultures, respectively. Other cultivars, especially Goami and Goami2, which had less content of monacolin K could not seem to ferment normally because those didn't show red color. These results imply that Sangjuchalbyeo can be optimal rice cultivar as a commercial RYR which is well fermented rice and has high content of monacolin K.

• Journal of Food Hygiene and Safety
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• v.22 no.2
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• pp.99-104
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• 2007

To defend putrifaction of the processed rice cake from gas-forming yeast during storage and distribution it needed to reduce and remove them. The sanitizers of ethanol and organic acids were applied on Pichia anomala, Candida tropicalis, and isolated yeasts from the putrified cut rice cake. Although growth inhibition effect by the sanitizer of 20% ethanol, 1% acetic acid, or 1% lactic acid respectively were very low, the combined sanitizer of 20% ethanol and 1% acetic acid, or 1% lactic acid showed very high sterilizing effect toward the yeasts. Six log cfu/ml of the yeast was reduced with this combined sanitizers for 30 minutes. In addition, the combined sanitizer heated from 20 to $50^{\circ}C$ had more the increased sterility. Therefore, the sanitizer of the combined ethanol with the acetic acid or the lactic acid for 30 minutes at $50^{\circ}C$ might reduce or sterilize the putrifying yeast at the processed rice cake. The result might be also applied to the effective pre-treatment of many agricultural food stuffs, against yeast, especially unsterilized stuffs, without any hazards from the special sanitizers and nutritional loss from harsh sterilization.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1098-1102
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• 2005

Properties of rice flours prepared from milled and broken rice produced by pre-washing and subsequent drying process were investigated. Compared to untreated ordinary milled rice, pre-washing process slightly increased lightness of rice flour, while decreased yellowness. Both WAI and WSI were higher in the flour from pre-washed rice, and gel consistency was the highest in the flour from pre-washed broken rice. Pre-washed rice showed increased amylograph peak viscosity and reduced setback values. On the other hand, pre-washed broken rice showed decreased peak viscosity and increased setback values. Differential scanning calorimetry (DSC) results showed that the pre-washing process reduced gelatinization onset- and peak temperatures, with increased gelatinization enthalpy. Total bacteria and yeast count were lower in the pre­washed rice, suggesting the pre-washing process could partially eliminate microbial contamination of ordinary milled rice.