• 한국식품영양학회지
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• 제31권1호
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• pp.117-126
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• 2018

Aronia makgeolli was manufactured using Asp. kawachi (AK) and Asp. awamori (AA) with tannase activity, and physicochemical properties were examined during the fermentation period. The pH was decreased during the fermentation period after the first day, while the acidity increased. Reducing sugars increased highly on the first day of fermentation, and then they gradually decreased as the fermentation period elapsed. On the 7th day of fermentation, it was in the range of 0.38~0.61%. The alcohol content gradually increased during the fermentation period and it ranged from 13.4~14.2 v/v% by the 7th day of fermentation, and the alcohol content of makgeolli added with Aronia was somewhat lower than that of makgeolli prepared without aronia. The L value increased as the fermentation period elapsed, and the L value of makgeolli added with aronia increased rapidly. The a value gradually decreased, while the b value gradually increased as the fermentation period elapsed. The content of total polyphenols increased during the fermentation period of AK makgeolli. However, the AA makgeolli was not significantly increased, as compared to the initial stage of fermentation, and it was lower than that of the AK makgeolli. The radical scavenging activity of the DPPH was higher in the makgeolli added with aronia, and the antioxidant activity of AA makgeolli was higher than that of AK makgeolli. In the sensory evaluation, in the AK makgeolli, the palatability deteriorated due to the bitter taste and the astringent taste derived from the aronia. However, in the AA makgeolli, astringent taste was very weak and the sensory quality was good.

• Mycobiology
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• 제42권4호
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• pp.353-360
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• 2014

Makgeolli is a traditional Korean alcoholic beverage. The flavor of makgeolli is primarily determined by metabolic products such as free sugars, amino acids, organic acids, and aromatic compounds, which are produced during the fermentation of raw materials by molds and yeasts present in nuruk, a Korean fermentation starter. In this study, makgeolli was brewed using the wild yeast strain Saccharomyces cerevisiae Y98-5, and temporal changes in the metabolites during fermentation were analyzed by ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. The resultant data were analyzed by partial least squares-discriminant analysis (PLS-DA). Various metabolites, including amino acids, organic acids, sugar alcohols, small peptides, and nucleosides, were obviously altered by increasing the fermentation period. Changes in these metabolites allowed us to distinguish among makgeolli samples with different fermentation periods (1, 2, 3, 6, 7, and 8 days) on a PLS-DA score plot. In the makgeolli brewed in this study, the amounts of tyrosine ($463.13{\mu}g/mL$) and leucine ($362.77{\mu}g/mL$) were high. Therefore, our results indicate that monitoring the changes in metabolites during makgeolli fermentation might be important for brewing makgeolli with good nutritional quality.

• 한국식생활문화학회지
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• 제33권2호
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• pp.133-141
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• 2018

This study investigated the quality characteristics and antioxidant activities of Makgeolli (a traditional Korean rice wine) made with Etteum bell flower root (0.5, 1, 1.5, and 2% with steamed rice) during fermentation. The pH values of Makgeolli with Etteum bell flower root powder decreased after 3 days of fermentation and then increased after 5 days of fermentation. Sugar content decreased after 3 days of fermentation. Color evaluation showed the L values of these drinks decreased during fermentation, whereas a and b values both increased. The alcohol content of Makgeolli increased after fermentation, reaching a maximum concentration of 7.90-8.07% by the end of fermentation. Total phenolic compound contents and DPPH radical scavenging activities increased as the ratio of Etteum bell flower root increased. Sensory scores of Makgeolli fermented with 1.5% Etteum bell flower root ware greater than those of Makgeolli prepared by other treatments. Therefore, Makgeolli added with 1.5% Etteum bell flower root added considered to be the most suitable for manufacturing.

• Preventive Nutrition and Food Science
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• 제16권2호
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• pp.142-149
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• 2011

The purpose of this study was to elucidate the physicochemical and microbiological properties of Korean traditional rice wine, Makgeolli, supplemented with black garlic extract during fermentation. Black garlic extract was diluted with distilled water to produce 0.5% and 1.0% black garlic solutions. Those solutions were then used to make rice solutions which included 2 kg rice, 40 g Nuruk (a fermentation starter), and 14 g yeast. After being mixed, the rice solutions were fermented for 7 days in a water bath at $28^{\circ}C$. The alcohol contents of the control, 0.5% and 1.0% black garlic Makgeolli were 16.9, 16.0, and 16.2%, respectively. Total acidity, total soluble solids, and color increased throughout the fermentation process. There was an increase of microorganisms throughout the fermentation period in all the samples. Glucose was the highest free sugar, and succinic acid was the highest organic acid detected in all the samples. Thirty nine volatile compounds were detected in black garlic Makgeolli.

• Preventive Nutrition and Food Science
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• 제18권3호
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• pp.203-209
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• 2013

The objective of the present study was to evaluate the physicochemical and microbial properties of the Korean traditional rice wine Makgeolli, supplemented with banana during 6 day fermentation. The alcohol contents of the control and banana Makgeolli were 17.0 and 16.5%, respectively. The pH values decreased while total acidity, total soluble solids, and color values increased throughout the fermentation process. An increase in microorganism counts throughout the 6-day fermentation period was noted in all samples. The major free sugar and organic acid detected in all samples were glucose and succinic acid, respectively. There were 39 volatile compounds detected in the control and banana Makgeolli. The major ester detected was ethyl acetate (20.037 and 22.604% for the control and banana Makgeolli, respectively). The major alcohol compounds detected were 3-methylbutanol (20.933%) and 3-methyl-1-butanol (34.325%) in the control. 2-mtehyl-1-propanol (22.289%) and 3-methyl-1-butanol (39.851%) were the highest alcohol compounds detected in the banana Makgeolli.

• Mycobiology
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• 제42권4호
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• pp.361-367
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• 2014

Makgeolli, also known as Takju, is a non-filtered traditional Korean alcoholic beverage that contains various floating matter, including yeast cells, which contributes to its high physiological functionality. In the present study, we assessed the levels of ${\beta}$-glucan and glutathione in various yeast strains isolated from traditional Korean Nuruk and selected a ${\beta}$-glucan- and glutathione-rich yeast strain to add value to Makgeolli by enhancing its physiological functionality through increased levels of these compounds. Yeast ${\beta}$-glucan levels ranged from 6.26% to 32.69% (dry basis) and were strongly species-dependent. Dried Saccharomyces cerevisiae isolated from Nuruk contained $25.53{\mu}g/mg$ glutathione, $0.70{\mu}g/mg$ oxidized glutathione, and $11.69{\mu}g/g$ and $47.85{\mu}g/g$ spermidine and L-ornithine monohydrochloride, respectively. To produce functional Makgeolli, a ${\beta}$-glucan- and glutathione-rich yeast strain was selected in a screening analysis. Makgeolli fermented with the selected yeast strain contained higher ${\beta}$-glucan and glutathione levels than commercial Makgeolli. Using the selected yeast strain to produce Makgeolli with high ${\beta}$-glucan and glutathione content may enable the production of functional Makgeolli.

• Journal of Biosystems Engineering
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• 제43권3호
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• pp.229-236
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• 2018

Purpose: Makgeolli is a traditional alcoholic beverage made from rice with a fermentation starter called "nuruk." The concentration of alcohol in makgeolli depends on the temperature of the fermentation tank. It is important to monitor the alcohol concentration to manage the makgeolli production process. Methods: Data were collected from 84 makgeolli fermentation tanks over a year period. Independent variables included the temperatures of the tanks and the room where the tanks were located, as well as the quantity, acidity, and water concentration of the source. Software for the multilayer perceptron model (MLP) was written in Python using the Scikit-learn library. Results: Many models were created for which the optimization converged within 100 iterations, and their coefficients of determination $R^2$ were considerably high. The coefficient of determination $R^2$ of the best model with the training set and the test set were 0.94 and 0.93, respectively. The fact that the difference between them was very small indicated that the model was not overfitted. The maximum and minimum error was approximately 2% and the total MSE was 0.078%. Conclusions: The MLP model could help predict the alcohol concentration and to control the production process of makgeolli. In future research, the optimization of the production process will be studied based on the model.

• 한국식품조리과학회지
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• 제33권1호
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• pp.94-103
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• 2017

Purpose: This study developed sourdough bread according to consumers' preferencesby shortening the sourdough fermentation process time through addition of makgeolli to sourdough. Methods: Fermentation time was measured by adding makgeolli and water to wheat flour. Results: Fermentation time was shorter than that of starter made with only water and flour, with 5 hours of primary fermentation and 3 hours of secondary fermentation. The optimum mixing ratio was 400 g of flour, 192 mL of water, and 48 mL of makgeolli. An increase in makgeolli sourdough content decreased crude protein and moisture contents of white bread. Crude fat and ash contents increased, and volume of bread was decreased as sourdough increased. The height of bread prepared with makgeolli sourdough was lower than that of bread without makgeolli sourdough. According to the results of the texture measurement, hardness, gumminess, and chewiness of sourdough group were lower as the addition of sourdough increased. Addition of makgeolli sourdough to white bread resulted in decreased lightness, but increased yellowness of white bread. Preparation of white bread with addition of sourdough improved taste and flavor compared to bread prepared only with wheat flour. Conclusion: The highest sensory preference was observed for white bread prepared whit 5 g of sourdough.

• 한국식품영양과학회지
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• 제43권8호
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• pp.1283-1288
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• 2014

파인애플 과육과 심지를 첨가하여 막걸리를 제조하고 품질특성을 분석하였다. 발효기간 동안 pH, $^{\circ}Bx$의 측정값과 발효 후 알코올의 함량은 샘플들 간에 큰 차이를 보이지 않았다. 파인애플을 첨가한 막걸리의 총산도 값은 대조구에 비해 높았으며 특히 citric acid, tartaric acid, malic acid, pyroglutamic acid, lactic acid, propionic acid의 함량이 높았다. 반면 총 유리아미노산의 함량은 대조구에서 더 높았으며, methionine을 제외한 aspartic acid, serine, threonine, alanine, tryptophan, lysine 등의 유리아미노산 함량은 파인애플을 첨가하지 않은 막걸리에서 더 높게 측정되었다. 관능평가에서는 파인애플 막걸리가 대조구보다 색도를 제외하고 향, 맛, 전체적인 기호도에서 높은 값을 보였다.

• 한국식품영양과학회지
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• 제40권2호
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• pp.223-228
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• 2011

본 연구에서는 오이를 첨가한 막걸리의 특성을 알아보기 위하여 쌀의 20%만큼 오이를 첨가하여 막걸리를 제조한 후 이화학적 및 미생물학적 특성을 평가하였다. 발효 6일째 알코올 함량은 대조군 16.3%, 오이 막걸리 16.2%로 유의적인 차이가 없었으며, 발효 6일째 두 시료의 pH도 차이가 나타나지 않았다. 총산은 두 시료 모두 발효 1일째에 급격히 증가하고, 그 이후 완만히 증가하였다. 총 균수, 유산균수 및 효모수 모두 오이 막걸리가 대조군보다 높았으며, 색도는 대조군과 오이 막걸리 사이에 큰 차이가 나타나지 않았다. 유리당 중 glucose는 발효가 진행되면서 감소하였고, 대조군과 오이 막걸리 모두 succinic acid 함량이 가장 높았다. 휘발성 화합물 중 오이 막걸리에서 가장 많이 동정된 성분은 3-methyl-1-butanol, 2-methyl-1-propanol, ethyl acetate이었다.