• Food Science and Preservation
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• v.6 no.4
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• pp.463-468
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• 1999

The characteristics and quality of Yakju with addition of ginseng powder originated in Choongchungdo were evaluated. At result, pH was decreased at the beginning stage of two stages fermentation and then slowly increased. Total acidity were increased in the cases of all (A), (B) and (C) during the fermentation. (A) group used Nuruk, crude enzyme and powder yeast showed the highest pH of 7.08 and total acidity of 0.84 at the 4th day of fermentation. The alcohol contents of B(21.0%) and C(20.4%) used cultured yeast were higher than A(19.0%) used powder yeast at the 4th day of fermentation. Also, inhibition against alcohol fermentation by ginseng powder wasn't showed and amino nitrogen contents were higher in (A) and (C) with addition of crude enzyme. Free sugar were the highest in (A) used both Nuruk and crude enzyme such as glucose of 599.16, maltose of 129.11mg%. Free amino acids were much more in A(580.02mg%) than in B(527.48mg%) and C(538.74mg%). from the sensory evaluation, desirable color and flavor qulity for 40 ages was (A) and (B) which was used Nuruk, and that for 20 ages was (C) which was used crude enzyme. However the best taste and overall preference was (B) for 20 and 40 ages of all. Therefore to produce high quality Yauju and commercialize, studies of fermentation process in Yakju should proceed later.

• Culinary science and hospitality research
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• v.22 no.3
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• pp.11-21
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• 2016

This study investigated the quality characteristics and retarding retrogradation of sponge cakes made with red yeast rice (RYR) flour. RYR (Monascus nuruk) is known to help digestion, smooth blood flow, and have anti-cancer, anti-microbial, and inhibitory effects against biosynthesis of cholesterol and blood pressure. This studys aim' was to find the optimal proportion of RYR flour in sponge cake. RYR sponge cakes were prepared with various levels (0, 5, 10, 15 and 20%) replacement of wheat flour and were designated as the control (without RYR), RYR5, RYR10, RYR15 and RYR20 respectively. Specific gravity was the lowest in RYR15 at 0.57, and the baking loss rate was not significantly different among the samples (p<0.05). The dough yield was the highest in RYR15 at 96.61. The moisture contents was highest in order, control, RYR5, and RYR15 at 28.67%, 28.18%, and 26.82% respectively. The L-value of crust tended to increase according to the level of RYR, but the L-value of crumb decreased in accorddance with the the content of RYR. The a-value of crust also decreased according to the level of RYR, although the a-value of crumb increased in response to higher levels of RYR. The b-value tended to decrease with increases of RYR (p<0.05). RYR5 exhibited the highest pH at 8.63, compared with RYR15 (8.57). The hardness, which was measured after cooling for 1 hour, was the lowest in RYR15 at $163.33g/cm^2$ and the springiness was not different significantly (p<0.05). Cohesiveness was the highest in RYR10 at 133.06%. The chewiness was the highest in RYR10 at $391.63g{\cdot}cm$ and lowest in RYR15 ast $169.62g{\cdot}cm$. Avrami equation showed that RYR15 and RYR20 had the lowest Avrami exponent (n) at 0.0664 and 0.4983 respectively. Time constant (1/k) was the highest in RYR15 at 200.00. Sensory evaluation revealed that RYR15 was the highest in color (5.50), flavor (4.95), sweetness (4.90), chewiness (4.75), and overall acceptability (4.60).

• Journal of the Korean Society of Industry Convergence
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• v.20 no.5
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• pp.377-383
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• 2017

In this research, the improvement of Korean rice wine (makgeolli) with pine (Pinus koraiensis) extract addition was evaluated due to the increase in alcoholic Korean traditional beverage. Makgeolli fermentation was prepared using Korean rice and nuruk (traditional starter) supplemented by pine needle (MPN) and pine sprout (MPS) extract. The average of initial pH level for MPN was 3.95 and MPS was 4.55, the average of initial sugar content for MPN was 0.4% and MPS was 0.3%. The sugar content and pH level behavior were investigated every 24h during fermentation period. The observation of microbial colony was done at days 8 of fermentation period with three time sample dilution. Afterward, the physical appearance of fermentation solution and microbial development were investigated in the final of fermentation period. The number of yeast and LAB ($402{\times}103\;CFU/mL$) in MPN was greater than the yeast and LAB count in MPS ($224{\times}103\;CFU/mL$). The pH level obtained by addition pine sprout have value of R2 higher than addition of pine needles (leaf), the sugar content (%) behaviour was opposite with pH level behaviour.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.184-188
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• 2010

The goal of this study was to screen a useful yeast for Korean traditional pear Yakju (KTPY) brewing and develop its brewing process. Cooked non-glutinous rice and nuruk were mixed, and added into pear juice with various Saccharomyces cerevisiae and then fermented at $25^{\circ}C$ for 7 days. Among several alcohol fermentation yeasts, ethanol contents was the highest in pear Yakju made by S. cerevisiae K-7 and also showed high ethanol content in pear Yakju which was made by commercial S. cerevisiae C-2. Therefore, we selected S. cerevisiae K-7 and S. cerevisiae C-2 as suitable yeasts for brewing of KTPY. Maximal ethanol production (10.4%) was obtained when cooked non-glutinous rice (100 g) and nuruk (30 sp/g) were mixed and added into pear juice (600 ml) with S. cerevisiae K-7 (5%) and fermented at $25^{\circ}C$ for 7 days and also its antihypertensive angiotensin I-converting enzyme (ACE) inhibitory activity was 57.2%. Addition of antihypertensive starchy materials into the mash was not affected in ACE inhibitory activity and total acceptability of KTPY.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.223-228
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• 2011

Korean traditional rice wine, Makgeolli, has been widely consumed with increasing popularity in Korea. Also, there has been an increase in the varieties of Makgeolli for the younger generation. In this study, we examined the physicochemical and microbial properties of Makgeolli supplemented with cucumber during fermentation. Four hundred grams of cucumbers (20% of the total amount of rice) were grinded and added to the rice solution (2 kg rice and 3.12 L distilled water) along with the Nuruk (40 g) and yeast (14 g). After mixing the solution, it was fermented for six days in a water bath ($28^{\circ}C$). During the fermentation, the pH value of the cucumber Makgeolli fell from 5.88 to 3.94 on day-1, and steadily increased to a pH value of 4.48 by day-6. The total acidity of the cucumber Makgeolli sharply increased from 0.02 to 0.20% on day-1, and then slowly increased thereafter to 0.28% by day-6. After the 6-day fermentation, the L values of the control and the cucumber Makgeolli were similar. The total viable cell, lactic acid bacteria and yeast count of the control and the cucumber Makgeolli increased considerably after the 6-day fermentation process. Free sugar analysis showed that glucose contents decreased with increasing fermentation periods. The succinic acid content was the highest among all the organic acids. Thirty-nine volatile compounds were observed on the final day of fermentation in the cucumber Makgeolli.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1682-1689
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• 2013

The objective of the present study is to elucidate the physicochemical and microbial properties of Korean traditional rice wine, Makgeolli, supplemented with mulberry during the fermentation process. Four hundred grams of mulberries (20% of the total amount of rice) were ground and incorporated into the rice solution (3.5 L of distilled water, 2.0 kg of rice, 28.0 g of yeast, and 80.0 g of nuruk). The rice solution was then placed in a water bath set at $28^{\circ}C$ and left to ferment for 7 days. The alcohol contents between the control and mulberry Makgeolli were not significantly different. The pH values of the control and mulberry Makgeolli decreased and the total acidity values were elevated after a 7-day fermentation. In the microbial analysis, the total viable cell count, lactic acid bacteria count and yeast count increased considerably through the 7-day fermentation process. For all the samples, the glucose and succinic acid contents were highest among all free sugars and organic acids, respectively. Forty-eight different volatile compounds were found in all the samples after the 7-day fermentation process.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.551-557
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• 2008

In order to investigate the effect of different ingredients on the quality of Korean rice wines, 30% of rice were substituted by malt, corn, potato, soybean, glutinous millet, unpolished rice, glutinous rice, or non-glutinous rice, when rice wines were prepared. Physicochemical and sensory characteristics of the rice wines from the varying ingredients were evaluated. Sample rice wines were analyzed for ethanol, pH, total acid, amino acid, soluble solid, coloring degree, UV absorbance, reducing sugar, organic acids, and free sugars. After fermentation for 16 days, the ethanol contents ranged from 13.28 to 16.23%, while the total acid levels were within the range of 0.27 to 0.32%. The amino acid contents in eight samples ranged from 0.18 to 0.36%, while the soluble solid contents were within the range of 8.35 to $11.1^{\circ}$Bx. Among the eight samples tested, rice wine prepared with malt showed the highest level of coloring degree, UV absorbance, and reducing sugar levels, while rice wine prepared with potato showed the lowest value. Organic acid contents of rice wines prepared with soybean, glutinous rice, and non-glutinous rice showed the highest levels of succinic acid followed by acetic acid, citric acid, malic acid, and pyroglutamic acid. Free sugar contents of all rice wines showed the higher levels of glucose followed by fructose and maltose. Rice wines prepared with unpolished rice and corn showed the same highest overall sensory preference. By descriptive analysis, the overall mean sensory intensities of samples prepared with glutinous rice and non-glutinous rice, showed similar levels of 'sweetness', 'fruitiness', and 'freshness of aroma', while those samples prepared with soybean, glutinous millet, and potato showed stronger intensities of 'nuruk', 'grain aroma', and 'yellowness'. Rice wine prepared with corn showed middle ranges in all sensory attributes tested.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1829-1836
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• 2013

This study is carried out to investigate the physicochemical characteristics, microbial population, and sensory characteristics during fermentation of Korean traditional rice wine with addition of glutinous rice. The fed-batch fermentation of rice was performed by Nuruk and yeast for 10 days at $28^{\circ}C$ in a water bath. The four fermentation batches included 0, 10, 15 and 20% of glutinous rice based on the total rice contents. The growth of total viable cells, lactic acid bacteria (LAB), and yeasts were similar among the four batches during the fermentation period. The population for total viable cells and LAB were increased for the first 3 days, and decreased slowly until 10 days. The number of yeast cells was rapidly decreased after day 6, when the alcohol content reached about 15% for all the fermentation batches. Physicochemical characteristics, such as pH, total acidity, and reducing sugars, were not different with the increase of additional glutinous rice contents. The ethanol production was higher in Korean traditional rice wine from non-glutinous rice (17.1%) than ones from glutinous rice (15.8~16.7%). For the sensory evaluations, Korean traditional rice wine with 15% glutinous rice was highly preferred due to the highest sweetness.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.437-443
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• 2013

Rice wine (makgeolli) containing various amounts of mountain ginsengs (MG) are being prepared with nuruk and yeasts, and the physicochemical characteristics and contents of ginsenosides in MG-makgeolli were analyzed. Average particle size of MG powder is $29.1{\mu}m$. MG slice (20 g) or powder (0~20 g) and rice (3,000 g) were used for 12 days fermentation of makgeolli, makgeolli containing slice of MG (SW-makgeolli), makgeolli containing 2 g (PW1-makgeolli), 10 g (PW2- makgeolli), 20 g (PW3-makgeolli) of powder of MG, respectively. Soluble solids and pH levels show no differences between five kinds of makgeolli groups, whilst the presence of high amounts of MG (PW3-makgeolli) caused decreases in ethanol and acidity. Major free amino acids in MG-makgeolli are glutamic acid and arginine. Total contents of 14 ginsenosides are approximately 2.5 g/100 g of dried MG powder and major ginsenoside were ginsenosides Re, Rb1, Rb2, Rg1, Rc and Rf. During the propagation of makgeolli containing MG, the ginsenosides Rb1, Rb2, Rb3, and Rc decreased, whilst ginsenosides Rg3 and compound K increased highly. It indicates that ginsenosides in MG are metabolized to different forms of ginsenosides by brewing microorganisms.

• The Korean Journal of Mycology
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• v.24 no.4 s.79
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• pp.280-292
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• 1996

The fungal isolates of Mucorales, directly collected from Korean traditional raw materials of Nuruk (raw material for Korean rice wine) and Meju (raw material for Korean soysauces), were compared with those of Rhizopus oryzae purchased. The fungal isolates of Rhizopus, Mucor, and Absidia mostly identified as based on the morphological observations, were evaluated with the PCR-polymorphic bands. The PCR-polymorphic bands of the genomic DNA reacted with the primers of OPD series tenmer were various, but showed averaged 4 to 6 in the agarose-electrophoresis. The dissimilarity coefficient (DC) between two isolates were compared by the cluster analyses, dendrogams and polar ordinations. The isolates of R. oryzae known. showed several groupings within the lower value of DC and were divided to two groups of amylo-process and other fungi with other purposes. The isolates unidentified were identified by the DC made of this results. Taxonomy of these isolates made by the morphological observations were consistent with those resulted above in most case but not in all aspects. More works were needed with the isolates known for detail informations of Mucorales.