• 한국미생물·생명공학회지
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• 제18권5호
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• pp.506-510
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• 1990

쌀 전분을 이용하여 무증자 당화 발효법으로 쌀 탁주를 제조하였으며 증자 당화 발효법에 의한 종래적인 방법과 비교하였다. Rhizopus속 균주를 증자하지 않은 생쌀에 접종하여 통상적인 방법에 따라 koji를 제조하여 사용하였으며 원료미를 분쇄해여 증자하지 않은 상태로 발효하였다. 무증자 당화 발효의 경우 종래적 방법에 의한 발효의 경우보다는 최종 alcohol 함량이 pH 1.8 높았고 유기산 생성이 급격히 이루어져 별도의 pH 조정이 필요없었다. 효모의 숫자는 차이가 없었고 세균은 무증자의 경우 2단 사입 후 24시간 까지는 증자의 경우보다 많다가 발효가 종료될 시점에서는 비슷하였다. 발효가 끝난후 제성주로 하였을 때 무증자의 경우는 fusel oil 함량은 증자의 경우보다 적었고 아미노산 함량은 약 2배로 높았으며 원료미에서 유래된 생취(raw flavor)가 유지되었다.

• 한국수소및신에너지학회논문집
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• 제11권1호
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• pp.29-41
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• 2000

Anaerobic fermentation using Clostridium butyricum NCIB 9576, and photo-fermentation using Rhodopseudomonas sphaeroides E15-1 were studied for the production of hydrogen from Makkoli, fruits (orange & apple, watermelon & melon) and Tofu wastewaters. From the Makkoli wastewater, which contained $0.94g/{\ell}$ sugars and $2.74g/{\ell}$ soluble starch, approximately $49mM\;H_2/{\ell}$ wastewater was produced during the initial 18h of the anaerobic fermentation with pH control between 6.5-7.0. Several organic acids such as butyric acid, acetic acid, propionic acid, lactic acid and ethanol were also produced. From Watemlelon and melon wastewater, which contained $43g/{\ell}$ sugars, generated about approximately $71mM\;H_2/{\ell}$ wastewater was produced during the initial 24 h of the anaerobic fermentation. Tofu wastewater, pH 6.5, containing $12.6g/{\ell}$ soluble starch and $0.74g/{\ell}$ sugars, generated about $30mM\;H_2/{\ell}$ wastewater, along with some organic acids, during the initial 24 h of anaerobic fermentation. Makkoli and Tofu wastewaters as substrates for the photo-fermentation by Rhodopseudomonas sphaeroides E15-1 produced approximately 37.9 and $22.2{\mu}M\;H_2/m{\ell}$ wastewaters, respectively for 9 days of incubation under the average of 9,000-10,000 lux illumination at the surface of reactor using tungsten halogen lamps. Orange and apple wastewater, which contained 93.4 g/l, produced approximately $13.1{\mu}M\;H_2/m{\ell}$ wastewater only for 2 days of photo-fermentation and the growth of Rhodopseudomonas sphaeroides E15-1 and hydrogen production were stopped.

• Journal of Animal Science and Technology
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• 제61권2호
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• pp.98-108
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• 2019

Four Korean native steers ($511{\pm}17.2kg$; $2{\times}2$ replicated crossover design) fitted with duodenal cannulas were used to investigate the influence of oral administration of soluble whey protein (WP; 82.29% crude protein) on ruminal fermentation, gastrointestinal (GI) hormone secretion in the blood, pancreatic ${\alpha}$-amylase activity in the duodenum, and disappearance rate in each segment of the GI tract. Steers were orally fed the basal diet (control; TMR [total mixed ration] 9 kg/d) or the basal diet with enriched WP (400 g/d) for 14 days. The apparent crude protein disappearance rate in the rumen of the WP was higher than in control (p < 0.05). However, no difference between groups was observed in the apparent crude protein disappearance rate in the intestine and the apparent starch disappearance rates in the rumen, GI tract. The level of cholecystokinin, secretin, and ghrelin in serum and pancreatic ${\alpha}$-amylase activity in the duodenum of the WP also did not change. The changes in the level of blood urea nitrogen related to protein metabolism were higher in the WP than in the control (p < 0.05). However, the levels of total protein, lipid, carbohydrate and mineral metabolites did not change. Consequently, we suggest that the oral administration of WP in steers assisted in ruminal fermentation due to the population increase of microbes in the rumen but did not improve the starch digestion rate in the small intestine because GI hormone secretion in the blood and pancreatic ${\alpha}$-amylase activity did not change.

• 한국작물학회지
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• 제59권1호
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• pp.66-72
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• 2014

Quality characteristics of yogurt with added colored barely flour was investigated during fermentation by lactic acid bacteria. Chemical properties such as moisture, crude protein, starch, ash and ${\beta}$-glucan contents was measured. pH, acidity, brix, Hunter color value and growth of lactic acid bacteria in yogurt was investigated during fermentation by L. acidophilus, L. bulgaricus, and S. thermophilus mixed culture. Crude protein contents of Daeanchal and Boseokchal was 16.16 and 12.17%, respectively. Starch contents of daeanchal were shown lower score. The pH of yogurt by addition of barley flour (Daeanchal) addition 0 and 20% were 6.66 and 6.40, respectively. The pH of yogurt supplemented with barley flour tended to be lower than before control which was not added barely flours and oligosaccharide in yogurt. Titratable acidity of yogurt added barley flour was higher compared with that of control. Brix of yogurt was decreased during fermentation by lactic acid bacteria. Lightness of yogurt added barley flour (Daeanchal) addition 0 and 20% were 83.25 and 69.83, respectively. The original microbial population of the yogurt during 0, 5, 8, and 15 hr fermentation were 7.48, 7.79, 8.15, and 8.71 Log CFU/g, respectively. Moreover, the addition of colored barley flour was to promote the proliferation of lactic acid bacteria in yogurt. In our research, addition of colored barley flours added into the yogurt may also have contributed to growth of lactic acid bacteria.

• 한국식품과학회지
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• 제23권6호
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• pp.683-688
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• 1991

단일축 압출조리기를 이용하여 밀가루를 조리한 후 탁주발효용 기질로 사용하여 알코올 수율을 조사하였다. 또한 스팀가열과 비교하여 압출조리에 의한 밀가루 전분질의 분자구조 변화와 효소 민감성에 대하여 gel permeation chromatography(GPC)와 고유점도 측정으로 평가하였다. 밀가루의 GPC patternd은 스팀 가열이나 방출조리에 의하여 크게 변화되지 않았다. 그러나 ${\alpha}-amylase$를 30분간 처리할 경우 압출성형된 밀가루의 맥아당 생산량이 크게 증가하며 GPC pattern도 크게 변하여 저분자 전분질의 함량이 증가하며 고유점도는 감소하였다. 압출성형된 밀가루로 탁주발효를 한 결과 스팀증자된 밀가루로 탁주발효를 한 경우보다 실험실 규모 실험에서는 26%의 알콜생산 증대가 기록되었으며 공장규모 발효에서는 10% 이상의 알콜생산 증대를 얻을 수 있었다.

• 한국수소및신에너지학회논문집
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• 제16권1호
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• pp.17-24
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• 2005

We experimented on growth in light and production of hydrogen and organic matters in dark fermentation by using C. reinhardtii. In the light, growth rate of C. reinhardtii following $CO_2$ fixation was proportional to consumption rate of nitrogen source. And the starch in cell was accumulated more when the period of culture was lengthened more. But the accumulation rate of starch in cell was decreased when the growth rate of cell become dull. In the dark fermentation, the production volume and production rate of hydrogen were the highest value in the mid exponential state among other states. The utilization efficiency of substrate was better in the early exponential state than other states. In production of organic matters, acetic acid didn't change remarkably and ethanol showed the highest value in early exponential state.

• Korean Chemical Engineering Research
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• 제51권6호
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• pp.709-715
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• 2013

맥주 폐 효모액(waste from beer fermentation broth, WBFB)은 바이오 에탄올 생산을 위한 우수하고 저렴한 원료이다. 본 연구에서는 바이오 에탄올 생산을 위해 WBFB의 당화능과 발효능을 확인하는 실험을 진행하였다. 당화능은 온도를 30, 40, 50, 60, $70^{\circ}C$로 다르게 하여 실험했는데 온도가 올라감에 따라 당화능은 증가하였고 4시간 후 $60^{\circ}C$와 $70^{\circ}C$에서 많은 양의 glucose가 생산되었다. WBFB와 chemically defined media (CDM) 혼합물에서는 어떠한 미생물의 첨가 없이도 발효가 되어 에탄올이 생산되었다. 동시당화발효능을 30, 40, 50, $60^{\circ}C$의 다양한 온도에서 실험해본 결과 $30^{\circ}C$에서 에탄올이 가장 많이 생산되었다. 또 이 실험은 WBFB, starch 용액 그리고 CDM을 이용하여 수행하였는데 WBFB에 있는 당화 효소와 효모가 어떠한 추가적 미생물 첨가 없이 당화와 발효를 가능케 하는 요인이었다.

• 한국식품과학회지
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• 제24권1호
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• pp.54-58
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• 1992

국내 시판용 옥수수 전분을 시료로 하여 그 호화액의 전분농도와 측정온도에 따른 리올로지 특성을 조사하였다. $4{\sim}9%$ 옥수수 전분 호화액의 리올로지 거동은 Herschel-Bulkley 식에 적합하였고, 항복응력을 갖는 의가소성 유체의 특성을 나타내었다. 전분농도의 증가로 의가소성은 증가하였으나 의가소성의 온도의존성은 보이지 않았고, 겉보기 점도와 항복응력은 모두 지수함수적인 농도 및 온도의존성을 나타내었다. 이들 농도 및 온도에 따른 유동특성을 해석한 결과, 옥수수 면분 호화액에서 졸-겔 전이와 같은 구조적 변화를 일으키는 농도 및 항복응력을 나타내기 시작하는 농도는 각각 $6.22{\sim}6.52%$ 및 $2.6{\sim}6.52%$이었다.

• 산업식품공학
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• 제21권4호
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• pp.341-350
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• 2017

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

• Asian-Australasian Journal of Animal Sciences
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• 제20권2호
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• pp.214-219
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• 2007

A $3{\times}3$ factorial design experiment was conducted to investigate the effect of temperature and duration of storage on the fermentation quality of potato pulp ensiled with two fungal inoculants under laboratory conditions. The inoculants, Rhizopus oryzae (R) and Amylomyces rouxii (A) were each added to potato pulp material to contain at least $1{\times}10^6$ CFU/g fresh matter, and silages without additives served as controls. The silages were stored under three temperature regimes; 4, 12 and $25^{\circ}C$. Three silos per treatment from every temperature regime were opened on days 7, 24 and 40 days after ensiling to investigate treatment effects on fermentation quality, starch and sugar concentrations. Increase in temperature and duration of storage had a positive significant effect (p<0.01) on the fermentation quality of potato pulp silage (PPS). The inoculants had little effect (p>0.05) on the fermentation quality of the silages. Sugar concentration in the silages decreased with increase in temperature (p<0.01) but increased (p<0.05) with progression of duration of storage. The fungal inoculants had no effect on starch degradation in PPS. The results suggest that storage temperature and duration of storage are more important in determining the rate of fermentation than addition of the fungal inoculants in PPS.