• Korean journal of food and cookery science
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• v.11 no.3
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• pp.282-286
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• 1995

Physicochemical properties of Jeungpyun dough were analyzed during fermentation in the ranges of 0 to 10 hours. Solube Protein and total content of free amino acid of Jeungpyun dough were decreased at the early stage of fermentation, recording minimum value, 0.292 mg/g-dry matter and 13.31 mg/100g-dry matter at fermentation time, 2 hours and 4 hours respectively while they were increased since then. It was observed that, although few changes occurred at the early stage of fermentation, the height of peak on X-ray diffractogram was decreased somewhat and some disintegration of starch granule on scanning electron micrograph occurred slightly in dough samples of above 6 hours of fermentation time.

• Microbiology and Biotechnology Letters
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• v.51 no.2
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• pp.184-190
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• 2023

Bioethanol has recently attracted much attention as a sustainable and environmentally friendly alternative energy source. This study aimed to develop a potential process for bioethanol production by fed-batch fermentation using instant dry yeast. To obtain the highest cell growth, we studied the influence of the initial sugar concentrations and pH of sugarcane molasses in batch fermentation. The batch system employed three levels of sugar concentrations, viz. 10%, 15%, 20% (w/v), and two levels of pH, 5.0 and 5.5. The highest cell growth was achieved at 20% (w/v) and pH 5.5 of molasses. The fed-batch system was then performed using the best batch fermentation conditions, with a molasses concentration of 13% (w/v) which resulted in high ethanol concentration and fermentation efficiency of 15.96% and 89%, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.479-485
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• 2017

Objective: The effects of particle size of processed barley grain, enzyme addition and microwave treatment on in vitro dry matter (DM) disappearance (DMD), gas production and fermentation pH were investigated for feedlot cattle. Methods: Rumen fluid from four fistulated feedlot cattle fed a diet of 860 dry-rolled barley grain, 90 maize silage and 50 supplement g/kg DM was used as inoculum in 3 batch culture in vitro studies. In Experiment 1, dry-rolled barley and barley ground through a 1-, 2-, or 4-mm screen were used to obtain four substrates differing in particle size. In Experiment 2, cellulase enzyme (ENZ) from Acremonium cellulolyticus Y-94 was added to dry-rolled and ground barley (2-mm) at 0, 0.1, 0.5, 1, and 2 mg/g, while Experiment 3 examined the interactions between microwaving (0, 30, and 60 s microwaving) and ENZ addition (0, 1, and 2 mg/g) using dry-rolled barley and 2-mm ground barley. Results: In Experiment 1, decreasing particle size increased DMD and gas production, and decreased fermentation pH (p<0.01). The DMD (g/kg DM) of the dry-rolled barley after 24 h incubation was considerably lower (p<0.05) than that of the ground barley (119.1 dry-rolled barley versus 284.8 for 4-mm, 341.7 for 2-mm; and 358.6 for 1-mm). In Experiment 2, addition of ENZ to dry-rolled barley increased DMD (p<0.01) and tended to increase (p = 0.09) gas production and decreased (p<0.01) fermentation pH, but these variables were not affected by ENZ addition to ground barley. In Experiment 3, there were no interactions between microwaving and ENZ addition after microwaving for any of the variables. Microwaving had minimal effects (except decreased fermentation pH), but consistent with Experiment 2, ENZ addition increased (p<0.01) DMD and gas production, and decreased (p<0.05) fermentation pH of dry-rolled barley, but not ground barley. Conclusion: We conclude that cellulase enzymes can be used to increase the rumen disappearance of barley grain when it is coarsely processed as in the case of dry-rolled barley. However, microwaving of barley grain offered no further improvements in ruminal fermentation of barley grain.

• Korean Journal of Human Ecology
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• v.5 no.1
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• pp.48-61
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• 2002

This study was carried out to investigate the effects of four kinds of leavening agents on Jeung-Pyun fermantation. Milk-wine(M), fresh yeast(F), dry yeast(D), instant yeast(I) were used in Jeung-Pyun ingredients. The physicochemical properties, sensory evaluation were examined. The results of this study are summarized as follows: 1. Basic recipes for Jeung-Pyun by preliminary test were developed. 2. Specific volumes and expansion ratio of Jeung-Pyun was higher in the fresh yeast-added sample. 3. The pH of Jeung-Pyun was decreased significantly as the fermentation progressed 4. In the result comparing Jeung-Pyun extracting after 1st fermentation with Jeung-Pyun extracting 2nd fermentation by SEM, the former was widely distributed in stability of bubble and pore than the latter. 5. Standard recipe by Q.D.A. test added four kinds of leavening agents were as follows: (1)Jeung-Pyun added milk wine was 240min for 1st fermentation time, 60min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 80% for fermentation humidity respectively. (2) Jeung-Pyun added fresh yeast was 90min for 1st fermentation time, 40min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 80% for fermentation humidity respectively. (3)Jeung-Pyun added dry yeast was 90min for 1st fermentation time, 60min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 60% for fermentation humidity respectively. (4)Jeung-Pyun added instant yeast was 90min for 1st fermentation time, 40min for 2nd fermentation time, 30$^{\circ}C$ for fermentation temperature, 60% for fermentation humidity respectively. 6.Based on sensory evaluation, Jeung-Pyun added fresh yeast was significantry higher than others in color, sweetness, moistness, softness, and overall quality. There was negative significance between milk wine flavor and astrigentness, and yeast flavor.

• The Korean Journal of Community Living Science
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• v.11 no.1
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• pp.1-8
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• 2000

The characteristics of rice-breads with wet-milling and dry-milling rice-flours were investigated. Rice-breads by wet-milling had a good fermentation than the breads by dry-milling. Also, the fermentation of mugwort rice-breads was lower than those. Rice-breads by dry-milling indicated the higher value in hardness and the lower value in springiness, cohesiveness and chewiness than rice-breads by wet-milling. Also, mugwort rice-breads was the higher value in hardness, springiness, chewiness and the lower value in cohesiveness than rice breads. The test of the sensory characteristics for rice-breads showed that moistness, springiness, chewiness was higher for rice-breads by wet-milling. The sensory characteristics of mugwort rice-breads were lower than those, of rice-breads except the chewiness. Overall quality of rice-breads by wet-milling was higher than that of rice-breads by dry-milling. The overall quality of mugwort rice breads was higher than that of rice-breads by wet-milling, but lower than that of rice-breads by dry-milling.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.279-284
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• 2020

This study aimed to analyze ruminal fermentation, methane emissions, and methanogen levels for different forage feed type and concentrate feed ratios. Alfalfa hay, oat hay, and a feed concentrate were used for in vitro fermentation experiments, at ratios of 9:1, 5:5, and 1:9 (forage:concentrate). After 24 h of incubation, rumen fermentation and methanogen level changes were evaluated. In the low forage treatments, the total gas, CH4, NH3-N, true dry matter digestibility, and total volatile fatty acid were higher than the other treatments, which were used as the parameters on which to assess rumen fermentation (P < 0.05). The feed ratio influenced the copy number for the total archaea and the genus Methanobrevibacter (P = 0.015, P = 0.010). The copy number result trend was like that for CH4 per digested dry matter (DDM). The PCR results and methanogen copy number analysis indicated that the composition of the methanogens affected the CH4 levels, not their copy number. The results of this study can be applied to predict rumen fermentation and methane emission patterns for cattle fed a variety of feedstuffs.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.3
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• pp.383-388
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• 1993

Three experiments were conducted to investigate the effect of cellulose addition on high (Exp. I) and low (Exp. II and III) dry matter barley straw silages. In Exp. I : 1 kg barley straw + 16 g glucose + 600 g water + 0 g as control (E0G), + 2 g (E2G), + 4 g (E4G), + 6 g (E6G), and + 8 g (E8G) of cellulose as treatments were ensiled. In Exp. II and III, 10 g glucose was and was not added, respectively, into 2 kg barley straw + 0 g (E8W, E8T) of cellulose as treatments. Samples were stored for 10 (Exp. I) and 7 (Exp. II and III) months at $21^{\circ}C$. The effect of cellulose addition on the fermentation and breakdown of the polysaccharides component in the silos at ensiling occurred more markedly at low dry matter silages rather than at the high ones. All cellulose treated silages were well preserved (pH below 5 in Exp. I and below 4 in Exp. II and III), while lactic acid and ethanol concentration increased. The fibrous fraction (ADF, NDF, crude fiber, hemicellulose, and cellulose) significantly (p<0.01) decreased (except hemicellulose content in Exp. I) compared with corresponding untreated silages. In vitro dry matter digestibility values (IVDMD) were similar for all silages. The present study showed that cellulose addition improved the potential nutritional and fermentation quality of barley straw silage.

• New & Renewable Energy
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• v.7 no.3
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• pp.6-16
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• 2011

In order to study the utilization of seaweeds as an alternative renewable feedstock for bioethanol production, their properties of hydrolysis and fermentation were investigated. The seaweeds were well hydrolyzed with diluted sulfuric acid. The weight loss of seaweeds reached 75-90%, but only 12-51% of them was converted into reducing sugars after the acid-hydrolysis at $130^{\circ}C$ for 4-6h. The yield of reducing sugars increased with increasing the hydrolysis time up to 4h and then decreased thereafter. In contrast, the ethanol yield from the hydrolysates increased with hydrolysis time except for green seaweeds maximizing at 4h. Optimal fermentation time by Saccharomyces cerevisiae (ATCC 24858) varied with seaweeds; 48h for green seaweeds, 96h for brown and red seaweeds. The ethanol yield from the hydrolysate reached 138${\pm}$37mg/g-dry for green seaweeds, 258${\pm}$29mg/g-dry for brown seaweeds, and 343${\pm}$53mg/g-dry for red seaweeds, which correspond to approximately 1.5-4.0 times more than the theoretical yield from total reducing sugars in the hydrolysates. The results obtained indicate clearly that the non-reducing sugars or oligosaccharides dissolved in the hydrolysate played an important role in producing bioethanol. Considering the productivity and production cost of each seaweed, brown seaweeds such as Laminaria japonica and Undaria pinnatifida seem to be a promissing feedstock for bioethanol production.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.291-294
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• 2000

The production of polyhydroxybutrate(PHB) by Alcaligenes eutrophus NCIB 11599 was studied in a synthetic medium from whey as a sole carbon source. Especially pH-effect was treated and compared in this study. At the end of fermentation (A) unadjusted to pH, the dry cell weight, PHB concentration, and PHB conversion rate were 10.3g/L, 3.1g/L, and 30%, respectively. At the end of fermentation (B) adjusted to $pH(7.0{\sim}7.5)$, the dry cell weight, PHB concentration, and PHB conversion rate were 12.5g/L, 4.8g/L, and 41%, respectively. PHB conversion rate was about 10% higher on the fermentation (B) than on the fermentation (A).

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.450-457
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• 2004

In wine making, to perform yeast culture effectively, which is the most important factor, 5 strains of representative active dry yeasts were selected : Montrachet, Pasteur Champagne, Epernay II, Prise do Mousse, Lalvin W15. The results about fermentation properties were as follows. After 1 day of fermentation, the ethanol contents of Lalvin W15 wine and Montrachet wine were 5.4% and 4.0%. After 2 days of fermentation, the ethanol content of Lalvin W15 wine was 9.2%, which is the highest degree among all experimental groups. As for the content of sugar solution, the wine fermented by Lalvin W15 was the highest one. In acidic solution, fermentation activity of Prise de Mousse, Lalvin W15, Montrachet were highest degrees and Red wine fermentation activity of Prise de Mousse has shown the highest degree in its fermentation activity, if only initial SO$_2$ amounts were 200 ppm. In regard to the foaming tendency during fermentation, the size of foams in Montrachet was big and the amount of foams was a lot. The change in Brix during the fermentation became evident after two days. The Brix of Montrachet wine and Lalvin W15 wine was 3.0, a high initial fermentation speed. After 10 days of fermentation, total acidity of Lalvin W15 wine was 0.99g/100m1, the highest degree. After 3 days of fermentation, the ethanol content of Lalvin W15 wine was 7.4%, the highest degree. But after 9 days of fermentation Epernay II showed the higher ethanol concentration to 13.8%.