• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.257-263
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• 2003

The cellulases production in solid state fermentation (SSF) of Trichoderma harzianum FJ1 with high cellulases productivity using cellulosic wastes was investigated. Physical and chemical conditions of the fermentation, such as moisture content, initial pH, and composition of mixed substrate (wine waste, rice straw, and soybean flour) on FPase (Filter paper activity) production were examined. The enzyme production was optimized in the conditions of moisture content of 70%, pH 5.0, 3$0^{\circ}C$, and 1:1:1 composition of mixed substrate containing wine waste, rice straw, and soybean flour. The highest activities of FPA, CMCase, Xylanase, $\beta$-glucosidase, and Avicelase in the optimized culture conditions were 15.2, 69.1, 83.9, 29.2, and 4.2 unit/g-SDW in 5 day cultivation, respectively. Economical and efficient production of cellulolytic enzymes by T harzianum FJ1 using cellulosic wastes in solid state fermentation will contribute to the biological saccharification of cellulosic wastes with enormous potential resource value in future.

• Journal of the Korean Society of Food Culture
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• v.29 no.4
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• pp.355-363
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• 2014

The purpose of this study was to investigate the rheological characteristics of medium wheat flour mixed with bamboo leaf and lotus leaf powders. Rheological properties of the mixed flours were tested based on falling number, color, RVA, farinogram, and rheofermentometer analyses. Falling numbers increased with addition of bamboo leaf and lotus leaf powders. The L values of all mixed flours were less than that of control. The 1% mixed flour sample containing bamboo leaf and lotus leaf powders was not significantly different from 3% mixed flour. The a values of the mixed flour decreased as bamboo and lotus powders increased, whereas b values increased. Addition of bamboo leaf and lotus leaf powders to flour reduced peak viscosity, holding strength, and final viscosity. The set back values of mixed wheat flour containing bamboo leaf powder were lower than those of mixed wheat flour containing lotus leaf powder, suggesting that bamboo leaf powder suppressed retrogradation of flour compared to lotus leaf powder. In the farinogram, the water absorption and consistency of the flours containing bamboo and lotus leaf powders increased, whereas development time and stability decreased. The fermentation time of dough with lotus leaf powder was less than that of dough with bamboo leaf powder.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1161-1168
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• 2009

Ethanol production by the simultaneous saccharification and fermentation (SSF) of low-value rice wine cake (RWC) without cooking was investigated. RWC is the filtered solid waste of fermented rice wine mash and contains 53% raw starch. For the SSF, the RWC slurry was mixed with the raw-starch-digesting enzyme of Rhizopus sp. and yeast, where the yeast strain was selected from 300 strains and identified as Saccharomyces cerevisiae KV25. The highest efficiency (94%) of ethanol production was achieved when the uncooked RWC slurry contained 23.03% starch. The optimal SSF conditions were determined as 1.125 units of the raw-starch-digesting enzyme per gram of RWC, a fermentation temperature of $30^{\circ}C$, slurry pH of 4.5, 36-h-old seeding culture, initial yeast cell number of $2{\times}10^7$ per ml of slurry, 17 mM of urea as the nitrogen additive, 0.25 mM of $Cu^{2+}$ as the metal ion additive, and a fermentation time of 90 h. Under these optimal conditions, the ethanol production resulting from the SSF of the uncooked RWC slurry was improved to 16.8% (v/v) from 15.1% (v/v) of pre-optimization.

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.42-49
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• 1987

The acid production and sugar utilization of Lactobacillus helveticus YM-1 between Streptecoccus lactic ${ML}_3$ were investigated in skim milk, cultured broth filtrate and semi-synthetic medium. The effect of acid production by mixed culture and in cultured broth filtrate of the other party were more than that of single culture and self-cultured broth filtrate. When the two strains were cultured 12 hrs, Streptococcus lactis ${ML}_3$ utilized with 0.4% lactose, Lactobacillus helveticus YM-1 with 0.85%, and mixed strains with 1.05% respectively. In 8 hrs fermentation Lactobacillus helveticus YM-1 and mixed strains accumulated 0.22%, 0.10% glucose in the medium respectively, and then decreased gradually. The glucose released by Lactobacillus helveticus YM-1 was stimulated the acid production of Streptococcus lactis ${ML}_3$.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.49-55
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• 2001

For the production of probiotic feed enriched with viable yeasts, aerobic liquid culture of Kluyveromyces marxianus was attempted in pulverized residual food wastes. After the preliminary shaking culture result, the liquid food wastes was added with urea($0.5g/{\ell}$), o-phosphate($0.4g/{\ell}$ ), molasses($4g/{\ell}$), and yeast extract($1g/{\ell}$), and the fermentation was carried out in 2-litre jar fermenter. In 12 hours of aerobic mixed culture with Aspersillus oryzae, viable cell count of the yeast reached to the number of $1.4{\times}10^{10}/{\ell}$ in the cultured medium.

• Preventive Nutrition and Food Science
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• v.21 no.3
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• pp.221-226
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• 2016

A new type of doenjang was manufactured by mixing soaked soybean, koji (Rhizopus oryzae), cheonggukjang (Bacillus amyloliquefaciens MJ1-4 and B. amyloliquefaciens EMD17), and Pichia farinosa SY80 as a yeast, salt, and water, followed by fermentation with koji that was made by fermenting whole wheat with R. oryzae. The mixed culture doenjang was designed to have a more palatable flavor and stronger biological activities than the conventional product. The extract of mixed culture doenjang showed higher antioxidant activity than the commercial doenjang as evaluated by the ferric reducing antioxidant power assay although it was not significantly different from the commercial product in 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activities. Further, the mixed culture doenjang reduced intracellular reactive oxygen species levels and protected cells from glutamate-induced cytotoxicity more efficiently in human hippocampal HT22 neuroblastoma cells than the commercial doenjang. In conclusion, a newly-developed mixed culture doenjang had a strong antioxidant activity in vitro and cultured cell model systems, exhibited a potential to prevent oxidative stress-associated disorders although animal and clinical studies are needed to confirm its in vivo efficacy.

• Korean Journal of Agricultural Science
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• v.43 no.1
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• pp.80-86
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• 2016

An in vitro trial was conducted to examine the effects of total mixed rations (TMR) on fermentation characteristics and effective degradability (ED) by rumen microbes. Three TMR diets were growing period TMR (GR-TMR, 67% TDN), early fattening period TMR (EF-TMR, 75.4% TDN) and late fattening TMR (LF-TMR, 80% TDN). Three TMR diets (3 g of TMRs in each incubation bottles) was added to the mixed culture solution of stained rumen fluid with artificial saliva (1:1, v/v) and incubated anaerobically for 48 hours at $39^{\circ}C$. The pH in all incubation solutions tended to decrease up to 48h, but the opposite results were found in concentration of total gas production, ammonia-N and total VFA in all incubations.The total gas production (p<0.05) in LF-TMR was highest compared with those of other diets. Also, concentration of total VFA was tended to increase in LF-TMR compared with other TMR diets in all incubations. The EDDM in both EF-TMR and LF-TMR was tended to high compared with GR-TMR (p=0.100). In this in vitro trials, concentration of propionate in all incubation solution was not affected by increased concentration of TDN. The results of the present in vitro study indicate that TMR may provide more favorable condition for nutrient digestion both in the rumen.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.660-665
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• 2008

The aim of this work was to investigate the microbiological and physicochemical properties of the rice sourdough for Jeungpyun prepared by mixed culture of Saccharomyces cerevisiae (S. cerevisiae) and Leuconostoc mesenteroides (L. mesenteroides) strains. The rice sourdough was fermented with S. cerevisiae and L. mesenteroides strains in rice dough for 24 hours at $30^{\circ}C$. Growth of L. mesenteroides strain was decreased after inoculation, however, it increased again after 18 hours of dough fermentation, and the growth of S. cerevisiae showed a typical growth pattern. Also, total aerobic microorganisms counts in rice sourdough were decreased due to the produced organic acids and ethanol during dough fermentation. These products led to a favorable fermentative quotient (FQ; molar ratio between lactic to acetic acid) value of $1.9{\sim}3.2$ and more stable fermentation for rice sourdough formation. The expansion ratio and viscosity were considerably increased by mixed cultivation of S. cerevisiae and L. mesenteroides strains. Addition of the brown rice at 10% (w/w) to dough preparation increased the relative expansion ratio to the highest value.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.131-135
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• 1988

Lactobacillus acidophilus KFCC12731 and Saccharomyces cerevisiae KFCC32017 were incubated together in soymilk and the conditions for acid production were investigated. The acid production of Lactobacillus acidophilus was much higher when this organism was incubated with Saccharomyces cerevisiae in soymilk than when it was incubated alone. Optimum acid production by the mixed cultures of Lactobacillus acidophilus and Saccharomyces cerevisiae was achieved with the following conditions; a temperature of 34$^{\circ}C$, a 3:7-8:2 (OD 660) ratio of Lactobacillus acidophilus to Saccharomyces cerevisiae at inoculum, a 1.5% level of sucrose fortification or a 2.0-3.0 % level of skim milk powder fortification and a culture time of 12 hours or more.

• Journal of Dairy Science and Biotechnology
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• v.36 no.3
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• pp.178-185
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• 2018

Kefir, which originates in the Caucasian mountains, is a cultured milk beverage produced by a combination of acidic and alcoholic fermentation. Kefir products are commonly used as food vehicles to deliver health-promoting materials including kefran and lactic acid bacteria to consumers. The aim of this study was to develop a freeze-dried starter culture without yeast and assess the suitability of kefir-like dairy products for the growth of lactic acid bacteria and the acidification of milk. Pasteurized whole milk (SNF 8.5%) stored at $25^{\circ}C$ was aseptically inoculated with starter cultures (0.002% w/v); it was kept at $25^{\circ}C$ until the pH attained a value of 4.6. Ten grams of the kefir-like product sample was diluted with 90 mL of 0.15% peptone water diluent in a milk dilution bottle, followed by uniform mixing for 1 min. Viable cells of Lactobacillus species were enumerated on modified-MRS agar (pH 5.2), with incubation at $37^{\circ}C$ for 48 h. Viable cells of Lactococcus species were enumerated on M17-lactose agar, with incubation at $32^{\circ}C$ for 48 h. The pH attained a value of 4.6 after fermentation for 9 h 30 min (Starter 1), 9 h 45 min (Starter 2), and 12 h (Starter 3). The viable cell count of Lactobacillus sp. and Lactococcus sp. was initially $10^5{\sim}10^6CFU/g$; it increased significantly to $10^9CFU/g$ after 12 h of incubation. During the storage of the kefir-like products at $4^{\circ}C$ for 1 4 days, the total viable cell numbers were unchanged, but the pH decreased slightly. The consistency of the kefir products increased gradually during the storage. The organoleptic properties of the kefir products fermented using the new starter culture are more desirable than those of commercial kefir. These results suggest that the newly developed starter culture without yeast could be suitable for kefir fermentation.