• Journal of Ginseng Research
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• 제31권4호
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• pp.191-195
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• 2007

Red ginseng sikhye is one of Korean unique beverages with the addition of effective ingredients of ginseng. Considering economical and mechanical efficiency and quality of sikhye, the optimum conditions for saccharification is to saccharify at 90 degree celsius for 3 hours in the composition of 4% of malt, 20% of steamed rice, and 6% of red ginseng power. The red ginseng sikhye has high soluble solid content over 33% compared with conventional commercial sikhye. On the other hand, ginseng sikhye, which shows low pH, has more or less higher acidity than conventional commercial one. Especially the turbidity of the red ginseng sikhye is much higher than that of commercial sikhye, due to as high amount of rice as 20% compared with 3% in the commercial one. The use of high quantity of rice affected the level of turbidity in red ginseng sikhye. In this study, we wanted to establish optimum conditions for saccharification in manufacturing red ginseng sikhye which contains effective herbal medicinal ingredients maintaining the original taste of traditional sikhye.

• 펄프종이기술
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• 제42권5호
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• pp.15-23
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• 2010

Bio-ethanol is the most potential next generation automotive fuel for reducing both consumption of crude oil and environmental pollution from renewable resources such as wood, forest residuals, agricultural leftovers and urban wastes. Lignocellulosic based materials can be broken down into individual sugars. Therefore, saccharification is one of the important steps for producing sugars, such as 6-C glucose, galactose, mannose and 5-C xylose, mannose and rhamnose. These sugars can be further broken down and fermented into ethanol. The main objective of this research is to study the feasibility and optimize saccharification and fermentation process for the conversion of lignocellulosic biomass to low cost bioethanol.

• Journal of the Korean Wood Science and Technology
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• 제36권5호
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• pp.56-65
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• 2008

In this paper experimental results are presented for the rheological behavior of high-solids saccharification of mixed northeast hardwood as a model feedstock. The experimental determination of the viscosity, shear stress, and shear rate relationships of the 10 to 20 percent slurry concentrations with constant enzyme concentrations were performed under variable rotational speed of a viscometer (2.0 to 200 RPM) at combined temperatures (50 to $30^{\circ}C$) for the initial four hours. The viscosities of saccharification slurries observed were in the ranges of 0.024 to 0.028, 0.401 to 0.058, and 0.840 to 0.087 Pa s for shear rates up to 100 reciprocal seconds at 10, 15, and 20 percent initial solids (w/v) respectively. The fluid behavior of the suspensions was modeled using the power-law, the Herschel-Bulkley, the Casson, and the Bingham model. The results showed that broth slurries were pseudoplastic with a yield stress. The model slope increased and the model intercept decreased with increasing fermentation time at shear rates normal for the fermentor. The broth slurries exhibited Newtonian behavior at high and low shear rates during initial saccharification process. The solid particle size ranged from 57.8 to $70.0{\mu}m$ for $40^{\circ}C$ and from 44.0 to 57.5 11m for combined temperatures at 10, 15, and 20 percent initial solids (w/v) respectively.

• Food Science and Biotechnology
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• 제16권3호
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• pp.381-385
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• 2007

The objective of this experiment was to study the influence of feed moisture content on the degree of enzymatic hydrolysis of com starch in a twin screw extruder and the saccharification yield of the dried extrudate. The feed moisture content was set at 25, 30, and 35% and ${\alpha}$-amylase solution was directly injected into the feed section at a barrel temperature of $95^{\circ}C$ and screw speed of 250 rpm. Amyloglucosidase was used for the saccharification of the dried extrudate at a concentration of 0.055%(w/w). Expansion ratio and swelling factor of extrudates decreased with increasing the feed moisture content. Addition of ${\alpha}$-amylase during extrusion process raised reducing sugar content of extrudates which also increased with the feed moisture content. The saccharification yield of dried extrudate was higher for the extrudate with lower feed moisture content.

• 한국미생물·생명공학회지
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• 제15권2호
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• pp.75-79
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• 1987

알코올 발효의 증자공정중에서 많은 에너지가 소요되므로 이를 줄이기 위한 방안으로서 저온증자법으로 Vietnam 산 cassava를 원료로 저온증자의 가능성을 고온증자와 비교 검토하였다. 알코올 발효에 당화 및 액화효소는 저온 및 고온증자에서 동일한 량을 사용하였으며 저온증자의 발효 mash중 소비된 glucose의 알코올 전환수율은 0.468g alcohol/gr. glucose로서 고온증자보다 좋은 결과를 보였다. 그러나 발효 불순물인 fusel oil은 고온증자의 0.48％보다 저온증자에서 0.64％로 다소 많았으나 증류과정에서 에너지소비 증가는 없었다.

• 한국미생물·생명공학회지
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• 제19권4호
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• pp.331-336
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• 1991

섬유성 물질을 발효기질로서 사용하기 위하여, 분리균 Pseudomonas sp. LBC-505의 cellulase를 이용하여 여러 종류의 천연 섬유성 물질에 대한 당화실험을 행하였다. Cellulase 복합체의 생산은 glucose에 의하여 저해되었고 CMC, avicel, 밀기울, 볏짚 등의 섬유성 물질에 의해 유도되었으며, 55(w/v) 밀기울 배지에서 최대 효소활성을 나타내었다. CMCase 와 xylanase의 최적 효소 반응온도는$50^{\circ}C$였으며, $\beta$-glucosidase는 $55^{\circ}C$ 였다. 또한, 이들 효소의 최적 반응 pH 는 모두 6.6이었다. 조효소 단독처리에 의한 천연섬유소의 당화율은 낮게 나타났으나, 5%(v/v) HCl로 실온에서 24시간 전처리한 후 효소반응을 행한 결과 가수분해율이 18.4%(w/w)로 볏집이 가장 양호하였으며, 구성당은 주로 glucose, xylose 및 cellobiose 였다.

• KSBB Journal
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• 제29권5호
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• pp.307-315
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• 2014

Recently seaweed polysaccharides have been extensively studied for alternative energy application. Because their producing cost is high and efficiency low, their industrial applications have been limited. The main component of cell wall of red algae represented by Gelidiales and Gracilariales is agar. Red-algae agar or galactan, consisting of D-galactose and 3, 6-anhydro-L-galactose, is suitable for bio-product application if hydrolyzed to monomer unit. For the hydrolysis of algae, chemical or enzymatic treatment can be used. A chemical process using a strong acid is simple and efficient, but it generates together with target sugar and toxic compounds. In an enzymatic hydrolysis process, target sugar without toxic compounds generation. The objective of this review is to summary the recent data of saccharification by chemical and enzymatic means from red seaweed for especially focused on automobile industry.

• 한국미생물·생명공학회지
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• 제20권4호
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• pp.437-444
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• 1992

분쇄마찰매체함유 불균일상 효소반응계를 활용한 생전분의 무증자당화법은 고농도, 고순도의 포도당을 고효율로 직접 얻을 수 있는 새로운 당화법으로 이를 high fructose corn syrup(HFCS) 제조공정에 응용코져 연구하였다. 400g/$\ell$ 생전분을 24시간 무증자당화시켜 이성화반응에 적합한 고농도인 398g/$\ell$와 고순조인 98 포도당 용액을 농축과정을 거치지 않고 직접 얻을 수 있었다. 전분에 대한 포도당수율은 0.90으로, 미반응 잔유전분은 쉽게 원심분리되었으며, 재당화도 용이하였다. 또한 무증자당화액은 단백질성 변성물, 이온 등 불순물의 함량이 매우 적어, 이성화 반응 전단계인 분리 정제과정을 단순화할 수 있었다. 생성된 당용액의 고정화 포도당 이성화효소 기질로서의 적합성을 검토하여 우수한 결과를 얻었다. 생전분 직접당화법을 도입한 새로운 HFCS 제조공정은 액화/당화공정을 경유하는 기존의 공정에 비하여 여러가지 장점이 있어 산업적 활용이 기대되며, 이를 위한 후속연구가 요망된다.

• Journal of Microbiology and Biotechnology
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• 제32권1호
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• pp.117-125
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• 2022

Until recently, four types of cellobiose-fermenting Saccharomyces cerevisiae strains have been developed by introduction of a cellobiose metabolic pathway based on either intracellular β-glucosidase (GH1-1) or cellobiose phosphorylase (CBP), along with either an energy-consuming active cellodextrin transporter (CDT-1) or a non-energy-consuming passive cellodextrin facilitator (CDT-2). In this study, the ethanol production performance of two cellobiose-fermenting S. cerevisiae strains expressing mutant CDT-2 (N306I) with GH1-1 or CBP were compared with two cellobiose-fermenting S. cerevisiae strains expressing mutant CDT-1 (F213L) with GH1-1 or CBP in the simultaneous saccharification and fermentation (SSF) of cellulose under various conditions. It was found that, regardless of the SSF conditions, the phosphorolytic cellobiose-fermenting S. cerevisiae expressing mutant CDT-2 with CBP showed the best ethanol production among the four strains. In addition, during SSF contaminated by lactic acid bacteria, the phosphorolytic cellobiose-fermenting S. cerevisiae expressing mutant CDT-2 with CBP showed the highest ethanol production and the lowest lactate formation compared with those of other strains, such as the hydrolytic cellobiose-fermenting S. cerevisiae expressing mutant CDT-1 with GH1-1, and the glucose-fermenting S. cerevisiae with extracellular β-glucosidase. These results suggest that the cellobiose-fermenting yeast strain exhibiting low energy consumption can enhance the efficiency of the SSF of cellulosic biomass.

• 한국식품조리과학회지
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• 제12권1호
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• pp.60-73
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• 1996

This study was undertaken to investigate the effect of cereals on the physicochemical and sensory characteristics of Noti. Noti is one of Korean traditional pan-fried glutinous cereal cakes. Noti made from the steamed glutinous rice flour, glutinous Chinese millet flour, glutinous millet flour or glutinous Indian millet flour is saccharified with malt, and then pan-fried. Noti also has sweet taste without sugar added. In addition, Noti has elastic characteristic, high calorie and good flavor. Long storage makes it better taste. In this case, Noti was made from the steamed glutinous rice flour. By the sensory evaluation, color, flavor and moistness were unfavorable according to the storage. Consistency was not strongly increased when comparing with the common rice cake depending upon the storage. The texture tended to increase by storage period. Optimum conditions of the safe storage and overall acceptability were to add 15% malt and keep 6hr saccharification time at 60$^{\circ}C$. During the period of storage for 90 days, reducing sugar content was similar, moisture content was low and maintained, and the acid value was not increased abruptly. The hardness was not increased rapidly and fungal growth was considerably low. Cohesiveness and elasticity were increased during storage.