• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.826-831
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• 1989

The rheological properties of concentrated Kochujang (Korean red pepper paste)-water suspensions were investigated. The rheological behavior of Kochujang-water suspension was illustrated by Herschel-Bulkley equation. All Kochujang-water suspensions with 12.5-100% of water addition showed pseudoplasticity in yield stress at the shear rate range of $0.25-179.20sec^{-1}$., but at the shear rate above $5.16 sec^{-1}$, more shear thinning behavior was observed with increasing shear rate. Also, pseudoplasticity of the suspension became weak by increasing water addition and decreasing temperature, The temperature dependence of consistency index on Kochujang-suspension was very low and the values of consistency index was lowered by increasing solid contents, but as heating, the values of that was increased. It was suggested that the main components responsible for rheological behavior of the suspensions at high temperature might be undigested starch or protein in Kochujang. Also, the changes of rheological behavior with vinegar addtion was only due to dilution effect.

• Journal of Microbiology and Biotechnology
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• v.23 no.3
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• pp.364-374
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• 2013

Monacolin K and yellow pigment, produced by Monascus sp., have each been proven to be beneficial compounds as antihypercholesterolemic and anti-inflammation agents, respectively. However, citrinin, a human toxic substance, was also synthesized in this fungus. In this research, solidstate fermentation of M. purpureus TISTR 3541 was optimized by statistical methodology to obtain a high production of monacolin K and yellow pigment along with a low level of citrinin. Fractional factorial design was applied in this study to identify the significant factors. Among the 13 variables, five parameters (i.e., glycerol, methionine, sodium nitrate, cultivation time, and temperature) influencing monacolin K, yellow pigment, and citrinin production were identified. A central composite design was further employed to investigate the optimum level of these five factors. The maximum production of monacolin K and yellow pigment of 5,900 mg/kg and 1,700 units/g, respectively, and the minimum citrinin concentration of 0.26 mg/kg were achieved in the medium containing 2% glycerol, 0.14% methionine, and 0.01% sodium nitrate at $25^{\circ}C$ for 16 days of cultivation. The yields of monacolin K and yellow pigment were about 3 and 1.5 times higher than the basal medium, respectively, whereas citrinin was dramatically reduced by 36 times.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.6
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• pp.543-549
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• 2016

The objective of this study was to investigate quality properties of 'Cheonghyang' wine using different commercial yeast strains. Soluble solid content, pH level and total acidity of 'Cheonghyang' grape were $20^{\circ}Bx$, pH 3.5 and 0.66%, respectively. Total acidity ranged from 0.91~1.06% in the middle stage of fermentation and decreased to 0.77~0.82% when alcoholic fermentation finished. Alcohol content in wines ranged from 12.5% to 12.9% showing no significant difference in yeast strains. Wine fermented with Red Fruit had high volatile acid content (189.0 mg/L) whereas wine fermented with Fermivin indicated low volatile acid content (77.7 mg/L). Wines made with Montrachet, Fermivin and Aroma White had low brightness (L-value) compared to others. Results from sensory evaluation demonstrated that commercial wine yeasts, Montrachet and Fermivin, can be applied to improve sensory properties of 'Cheonghyang' wine such as aroma, acidity and transperency. On the other hand, preferences of wine fermented with EC-1118 strain containing lots of tannins and total polyphenols were significantly reduced.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.379-385
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• 2017

In this study, white ginseng was used as the raw material, which was fermented with Paecilomyces hepiali through solid culture medium, to produce ginsenosides with modified chemical composition. The characteristic chemical markers of the products thus produced were investigated using rapid resolution liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (RRLC-QTOF-MS). Chemical profiling data were obtained, which were then subjected to multivariate statistical analysis for the systematic comparison of active ingredients in white ginseng and fermented ginseng to understand the beneficial properties of ginsenoside metabolites. In addition, the effects of these components on biological activity were investigated to understand the improvements in the phagocytic function of macrophages in zebrafish. According to the established RRLC-QTOF-MS chemical profiling, the contents in ginsenosides of high molecular weight, especially malonylated protopanaxadiol ginsenosides, were slightly reduced due to the fermentation, which were hydrolyzed into rare and minor ginsenosides. Moreover, the facilitation of macrophage phagocytic function in zebrafish following treatment with different ginseng extracts confirmed that the fermented ginseng is superior to white ginseng. Our results prove that there is a profound change in chemical constituents of ginsenosides during the fermentation process, which has a significant effect on the biological activity of these compounds.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1243-1252
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• 2019

The purpose of this study is to investigate the optimum conditions of biomass pretreatment with potassium hydroxide (KOH) for efficient utilization of cellulose, hemicellulose and lignin from Miscanthus. The optimization of variables was performed by response surface methodology (RSM). The variation ranges of the parameters for the RSM were potassium hydroxide 0.2~0.8 M, reaction temperature 110~190℃ and reaction time 10~90 min. The optimum conditions of alkali pretreatment from Miscanthus were determined as follows: concentration of KOH 0.47 M, reaction temperature 134℃ and reaction time 65 min. At the optimum conditions, the yield of cellulose from the solid fraction after pretreatment was predicted to be 95% by model prediction. Finally, 66.1 ± 1.1% of cellulose were obtained by verification experiment under the optimum conditions. The order contents of solid extraction were hemicellulose 26.4 ± 0.4%, lignin 3.7 ± 0.1% and ash 0.5 ± 0.04%. The yield of ethanol concentration of 96% was obtained using separated saccharification and fermentation.

• Korean journal of food and cookery science
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• v.11 no.3
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• pp.226-232
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• 1995

This study is a result of the experiments to determine the optimum conditions of salting of Chinese cabbages for making tasty Kimchi. For the experiments, various methods of salting of Baechu were set up and the best method of salting had prepared Kimchi to investigated the best salt kind. In the two best results by method of salting salt kind, were investigated for salting time of Kimchi. There were certain amounts of Kimchi had prepared for each case of the combinations of the three conditions. Every case of Kimchi was refrigerated and was evaluated by sensory tests. In the salt concentration, pH and acidity of the Kimchi were measured. The results are as follows; In three cases of Kimchi, for salt concentration, level of 2.4-3.0$^{\circ}$ was maintained in Kimchi solid from the beginning to the end, while it was high in the beginning and gradually lowered in Kimchi liquid. The level of pH in both solid and liquid of Kimchi quickly dropped at the beginning of fermentation period and turned slow as time passed. And the level of acidity was increased little bit in the beginning, but it suddenly multipied until the third day of preservation. Since then, it had increased gradually thereafter as it was before. This experiments show that Kimchi can be the best taste in the case of Chinese cabbage soak in brine- free natural salt are kept for five hours.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.609-615
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• 2003

In the Kimchi manufacturing industry, the process of brining baechu produces a vast amount of high salinity waste water. To study if this brine can be recycled, the quality characteristics of Kimchi salted by waste brine(F), which was used five times successively, was compared with those salted using water after recycling filtration through sand (F1) and activated carbon (F2) columns. No significant difference in the salinity and soluble solid contents, during fermentation at 10 was observed among the samples, but the salinity and soluble solid contents of the F-sample were slightly higher than in the control. The F1 and control Kimchi showed similar pHs and titratable acidities, while the F-Kimchi had a lower pH and a higher acidity during fermentation. The numbers of total viable cells were highest in the F, and lowest in the F2-Kimchi, while the counts of lactic acid bacteria were lowest in the F-Kimchi. The sensory tests for appearance, odor, taste and overall acceptance showed that the F-Kimchi was the least desirable, the F2-Kimchi had lower sour odor and taste, and a higher toughness, than the others. The F1- and control Kimchi had similar sensory grades for appearance, odor, and tastes, and there were no significant difference in the overall acceptance, showing the possibility of recycling wastewaters as brine for the production of baechu Kimchi.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.13 no.1
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• pp.69-80
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• 2002

The grains were used as solid-substrate for the cultivation of basidiomycetes. The grains were fermented with Ganodema lucidum 7094, Fomitella fraxinea 81003, Phellinus igniarius 26005, and its free sugar composition was investigated. For the mass cultivation of mycelia, the hydrated grains with cold water were put into the plastic bottle. The mycelial growth rate in the bottled grains was high in the early stage with inoculation of homogenized mycelium. The activity of mycelium was maintained by adding sterilized water in the middle of cultivation. There was marked difference in the content of total free sugar and composition ratio of free sugar according to kinds of basidiomycetes. The content of free sugar increased far more in grains fermented with mycelium than in grains which was not fermented.

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.697-706
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• 2018

Lactobacillus pentosus K1-23 was selected from among 25 lactic acid bacterial strains owing to its high inhibitory activity against several pathogenic bacteria, including Escherichia coli, Salmonella typhimurium, S. gallinarum, Staphylococcus aureus, Pseudomonas aeruginosa, Clostridium perfringens, and Listeria monocytogenes. Additionally, among 13 strains of Aureobasidium spp., A. pullulans NRRL 58012 was shown to produce the highest amount of ${\beta}$-glucan ($15.45{\pm}0.07%$) and was selected. Next, the optimal conditions for a solid-phase mixed culture with these two different microorganisms (one bacterium and one yeast) were determined. The optimal inoculum sizes for L. pentosus and A. pullulans were 1% and 5%, respectively. The appropriate inoculation time for L. pentosus K1-23 was 3 days after the inoculation of A. pullulans to initiate fermentation. The addition of 0.5% corn steep powder and 0.1% $FeSO_4$ to the basal medium resulted in the increased production of lactic acid bacterial cells and ${\beta}$-glucan. The following optimal conditions for solid-phase mixed culture were also statistically determined by using the response surface method: $37.84^{\circ}C$, pH 5.25, moisture content of 60.82%, and culture time of 6.08 days for L. pentosus; and $24.11^{\circ}C$, pH 5.65, moisture content of 60.08%, and culture time of 5.71 days for A. pullulans. Using the predicted optimal conditions, the experimental production values of L. pentosus cells and ${\beta}$-glucan were $3.15{\pm}0.10{\times}10^8CFU/g$ and $13.41{\pm}0.04%$, respectively. This mixed culture may function as a highly efficient antibiotic substitute based on the combined action of its anti-pathogenic bacterial and immune-enhancing activities.

• The Korean Journal of Mycology
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• v.28 no.2
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• pp.97-102
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• 2000

The mycelial growth of Pleurotus ostreatus in compost is strongly stimulated by solid-state fermentation with thermophilic fungi which were isolated from oyster mushroom compost. The biochemical characteristics of these thermophilic fungi were investigated. Cellulase and ligninase activities were not detected by clear zone effect on CMC and lignin media. All of thermophilic fungi grew well with high mycelial density on xylan media and the growing rate of Sepedonium sp. S-2 observed very high. In results of MUF-test, extracellular enzyme activity of Sepedonium sp. S-2, and S-5 measured very high. On the compost after high temperature fermentation with Sepedonium sp. S-2 and S-5, the mycelial growing rate of Pleurotus ostreatus was increased about 50% and it also showed the inhibiting effect on mycelial growth of Trichoderma sp. SJG-51. Isolated thermophilic fungi, Sepedonium sp. S-2 and S-5 were expected as very useful organism for making oyster mushroom compost.