• 한국식품조리과학회지
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• 제7권2호
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• pp.7-18
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• 1991

This study was experimented saccharification process added malt extract solution into cooked sweet potato and potato with time, temperature and was tested reducing sugar changes, structural changes, pH and sensory evaluation about cooked shik-hae of rice, glutinous rice, potato, sweet potato. The results are summarized as follows: 1. Enzyme activity was highest in malt after four days of barley germination at a room temperature. 2. Electronmicroscopic observation indicated that raw starch granule of potato and that of sweet potato was 25-60$\mu\textrm{m}$ and 8~18$\mu\textrm{m}$ in size, respectively and its shape is oval and globular for potato and sweet potato respectively. 3. Reducing sugars were 1,682.6mg and 1,695.6mg in rice and glutinous rice, respectively, for 6-hour-saccharification at $50^{\circ}C$. Reducing sugars were 1,689.1mg and 1,497.8mg in sweet potato, potato, respectively, for 6.hour-saccharification at $60^{\circ}C$. 4. pH variation during saccharification for sweet potato and potato was pH 5.8~5.4. 5. Sensory evalution showed that there were more significant differences in sweety odor, roasted nutty taste and sweety taste of sweet potato among four samples than the other's color shininess.

• Journal of Microbiology and Biotechnology
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• 제29권6호
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• pp.905-912
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• 2019

Bioethanol has attracted much attention in recent decades as a sustainable and environmentally friendly alternative energy source. In this study, we compared the production of bioethanol by Candida molischiana and Saccharomyces cerevisiae at different initial concentrations of cellobiose and glucose. The results showed that C. molischiana can utilize both glucose and cellobiose, whereas S. cerevisiae can only utilize glucose. The ethanol yields were 43-51% from different initial concentrations of carbon source. In addition, different concentrations of microcrystalline cellulose (Avicel) were directly converted to ethanol by a combination of Trichoderma reesei and two yeasts. Cellulose was first hydrolyzed by a fully enzymatic saccharification process using T. reesei cellulases, and the reducing sugars and glucose produced during the process were further used as carbon source for bioethanol production by C. molischiana or S. cerevisiae. Sequential culture of T. reesei and two yeasts revealed that C. molischiana was more efficient for bioconversion of sugars to ethanol than S. cerevisiae. When 20 g/l Avicel was used as a carbon source, the maximum reducing sugar, glucose, and ethanol yields were 42%, 26%, and 20%, respectively. The maximum concentrations of reducing sugar, glucose, and ethanol were 10.9, 8.57, and 5.95 g/l, respectively, at 120 h by the combination of T. reesei and C. molischiana from 50 g/l Avicel.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권1호
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• pp.52-59
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• 2005

The study was targeted to saccharify foodwastes with the cellulolytic and amylolytic enzymes obtained from culture supernatant of Trichoderma harzianum FJ1 and analyze the kinetics of the saccharification in order to enlarge the utilization in industrial application. T. harzianum FJ1 highly produced various cellulolytic (filter paperase 0.9, carboxymethyl cellulase 22.0, ${\beta}$-glucosidase 1.2, Avicelase 0.4, xylanase 30.8, as U/mL-supernatant) and amylolytic (${alpha}$-amylase 5.6, ${\beta}$-amylase 3.1, glucoamylase 2.6, as U/mL-supernatant) enzymes. The $23{\sim}98\;g/L$ of reducing sugars were obtained under various experimental conditions by changing FPase to between $0.2{\sim}0.6\;U/mL$ and foodwastes between $5{\sim}20\%$ (w/v), with fixed conditions at $50^{\circ}C$, pH 5.0, and 100 rpm for 24 h. As the enzymatic hydrolysis of foodwastes were performed in a heterogeneous solid-liquid reaction system, it was significantly influenced by enzyme and substrate concentrations used, where the pH and temperature were fixed at their experimental optima of 5.0 and $50^{\circ}C$, respectively. An empirical model was employed to simplify the kinetics of the saccharification reaction. The reducing sugars concentration (X, g/L) in the saccharification reaction was expressed by a power curve ($X=K{\cdot}t^n$) for the reaction time (t), where the coefficient, K and n. were related to functions of the enzymes concentrations (E) and foodwastes concentrations (S), as follow: $K=10.894{\cdot}Ln(E{\cdot}S^2)-56.768,\;n=0.0608{\cdot}(E/S)^{-0.2130}$. The kinetic developed to analyze the effective saccharification of foodwastes composed of complex organic compounds could adequately explain the cases under various saccharification conditions. The kinetics results would be available for reducing sugars production processes, with the reducing sugars obtained at a lower cost can be used as carbon and energy sources in various fermentation industries.

• 한국환경농학회지
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• 제35권4호
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• pp.247-255
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• 2016

BACKGROUND: Acrylamide (CAS No. 79-06-1) is known to be a carcinogenic compound, and is classified as a Group 2A compound by the International Agency for Research on Cancer (IARC, 1994). Acrylamide can be generated during the browning process via the non-enzymatic Maillard reaction of carbohydrates such as reducing sugars and of amino acids such as asparagine, both of which occur at a temperature above $120^{\circ}C$. Potato tubers contain reducing sugars, and thus, this will affect the safety of processed potato products such as potato chips and French fries. In order to reduce the level of acrylamide in potato processed products, it is therefore necessary to understand factors that affect the reducing sugar content of potatoes, such as environmental factors and potato storage conditions, as well as understanding factors affecting acrylamide formation during potato processing itself. METHODS AND RESULTS: Potatoes were cultivated in eight regions of Korea; For each of these different environments, soil physico-chemical characteristics such as pH, electrical conductivity, total nitrogen, available phosphate, and exchangeable cation content were measured and correlations with potato reducing sugar content and potato chip acrylamide levels were examined. The reducing sugar content in potato during storage for three months was determined and acrylamide level in potato chip was analyzed after processing. The storage temperature levels were $4^{\circ}C$, $8^{\circ}C$, or $10^{\circ}C$, respectively. The acrylamide content of chips prepared from potatoes stored at $10^{\circ}C$ or $20^{\circ}C$ for one month was analyzed and the different frying times were 2, 3, 5, and 7 min. CONCLUSION: This study showed that monitoring and controlling the phosphate content within a potato field should be sufficient to avoid producing brown or black potato chips. For potatoes stored at low temperatures, a reconditioning period ($20^{\circ}C$ for 20 days) is required in order to reduce the levels of reducing sugars in the potato and subsequently reduce the acrylamide and improve chip coloration and appearance.

• Applied Biological Chemistry
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• 제19권1호
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• pp.36-40
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• 1976

본(本) 연구(硏究)에서 얻은 결과(結果)를 다음에 요약(要約)한다. 1. 황촉규근(黃蜀葵根) 점액(粘液)은 유리환원당(遊離還元糖)을 함유(含有)한다. 이것의 함량(含量)은 경시적(經時的)으로 변화(變化)하며 함량(含量)이 최고(最高)에 달(達)하는 시간(時間)은 온도(溫度), 침출수량등(浸出水量等)의 영향(影響)으로 일정(一定)하지 않다. 2. 황촉규근(黃蜀葵根) 점액(粘液)의 점도(粘度)도 경시적(經時的)으로 감퇴(減退)하며 이것의 점성(粘性)은 점액내(粘液內) 유리당(遊離糖)의 함량(含量)과 약간(若干)의 상관관계(相關關係)가 있어 일반(一般)으로 점도(粘度)가 큰 점액(粘液)의 당함량(糖含量)은 크다. 그리고 점액(粘液)의 점도(粘度)는 경시적(經時的)으로 급격(急激)하게 감퇴(減退)되나 당함량(糖含量)은 서서히 감소(減少)한다. 3. 황촉규근(黃蜀葵根) 점액(粘液)은 표피(表皮)에서 많이 분비(分泌)되며 이 점액(粘液)은 목질부(木質部) 분비(分泌)된 점액(粘液)보다 점도(粘度)가 크고 유리당(遊離糖)의 함량(含量)이 크다. 4. mixer처리(處理)로 점액(粘液)의 점도(粘度)는 크게 감퇴(減退)하나 당함량(糖含量)에는 큰 변화(變化)가 없다. 5. 점액(粘液)의 점도저하(粘度低下)는 ammonium sulfate의 첨가(添加)로 효과적(效果的)으로 방지(防止)할 수 있다. 그러나 이 경우의 유리당(遊離糖) 함량(含量)은 비교적(比較的) 적고, starch-iodine반응(反應)은 30일(日)이 경과(經過)한다 할지라도 양성(陽性)이다. 뒤의 여러 결과(結果)로 미루어 점액(粘液)의 점성(粘性)의 불안정성(不安定性)은 화학적(化學的), 물리적(物理的) 요인외(要因外)에 미생물학적(微生物學的) 요인(要因)이 복합(複合)되어 관련(關聯)될 것이라 추측(推測)된다.達)한 바 있으나 여기에서 점질물(粘質物)의 구성성분(構成成分)으로 glucose, ribose 등(等)이 관여(關與)할 것이라는 새로운 사실(事實)이 관찰(觀察)되었다. glucose는 점액(粘液) 그리고 모든 가수분해(加水分解) 생성물(生成物)에서 분리(分離), 동정(同定)되나 ribose는 점질물(粘質物)을 제거(除去)한 여액(濾液)의 가수분해(加水分解) 생성물(生成物)에서 분리(分離), 동정(同定)되고 약간(若干)의 시일(時日)이 경과(經過)한다 할지라도 동일(同一)한 결과(結果)를 보인다. 또 여기에서 더욱 검토(檢討)하여야 할 미지물질(未知物質)의 존재(存在)도 관찰(觀察)되었다. 4. 따라서 황촉규근(黃蜀葵根) 점액(粘液) 및 점질물(粘質物)의 구성(構成) 성분(成分)으로 확인(確認)된 당류(糖類)는 rhamnose, xylose, arabinose, galactose, glucose, ribose와 uronic acid 등(等)이며 이밖에 미지(未知)의 물질(物質)도 확인(確認)되었다. 그러므로 점질물(粘質物)의 본태(本態)는 이들이 결합(結合)히여 이루어진 복합당(複合糖)일 것으로 추측(推測)된다.有率)이 그 지방(地方)의 비추락지(非秋落地)에서보다 낮았고 소사(素砂)에서는 철(鐵), 평택(平澤)에서는 유기물(有機物)의 함유율(含有率)이 추락도(秋落稻)에서 높았다. (5) 상층토전체(上層土全體)에 함유(含有)되어 있는 각주요무기성분(各主要無機成分)의 전량(全量)에 대(對)하여 각(各) 지구(地區)를 통관(通觀)한 추락(秋落)과의 관계(關係)에 어떤 일정(一定)한 경향(傾向)을 인정(認定)할 수 없었으나 지구별단위(地區別單位)에 있어서는 질소(窒素) 그밖에 모든 성분(成分)에 있어서 차이(差異)가 있음을 인정(認定)할 수 있었다. 3. 수확물(收穫物)의 화학적(化學的)

• Journal of Nutrition and Health
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• 제8권4호
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• pp.33-37
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• 1975

This investigation was designed to determine the influence of drying methods on the free amino acids and free sugars in red pepper and to study the browning mechanism of brown-colored red pepper. Three different drying methods were employed: 1) Sun-drying at $25{\sim}28^{\circ}C$ for 15 days, 2) Drying in oven at $60^{\circ}C$ for 49 hours, and 3) Drying in oven at $90^{\circ}C$ for 8 hours. Dried and ground peels were used for the analysis of free amino acids and free sugars. The results were as follows; 1. Sixteen kinds of amino acids i.e. asparagine, methionine, and cystine etc. were identified. Total amino acid content of the sun-dried sample was not different from that of the fresh sample, but the samples dried at $60^{\circ}C$ and $90^{\circ}C$ in the oven were decreased to 24.9% and 67.4% respectively. Of amino acids identified, methionine, lysine and aspartic acid were decreased in all treatments. Especially, methionine ana aspartic acid were decreased rapidly to 71.8% and 73.3% , respectively. 2. Three kinds of free sugars i.e. glucose, fructose and sucrose were identified. The total content of free sugars was significantly decreased in each treatment. Among the reducing sugars, glucose was rapidly decreased; 65.9% for the glucose of sample dried at $90^{\circ}C$ in the oven. 3. At the higher drying temperature, the darker red color was found. Brown-color appeared at $90^{\circ}C-drying$ showed appreciable losses in carotenoid content, but the major color seems to be due to the large increase in browning compounds. 4. It was assumed that increased browning compounds of red pepper were due to the Maillard reaction which is a nonenzymatic browning process.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1258-1258
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• 2001

Estimation of sugar and reducing sugar content in molasses is very important task in sugar refineries. Conventional methods of determination of sugar content in molasses samples are highly time consuming and employ hazardous chemicals. Due to the physical properties of molasses, probability of error in conventional analytical techniques is high. These methods have proven to be inefficient for a process control in any sugar industry. Hence development of a rapid, inexpensive, physical and also accurate method for sugar determination in molasses will be highly useful. Near Infrared spectroscopy is being widely used worldwide as an analytical technique in food industry. The technique offers the advantage of being non-destructive and rapid. The present paper highlights the potential of near infrared reflectance spectroscopy as a rapid and automated analytical technique for determination of sugar and reducing sugar content in molasses. A number of molasses samples were collected during and after the sugar season from Havana Sugar Industry, Havana. The samples were chosen so as to obtain a wide range of concentration of sugar and reducing sugars. This was done in order to achieve a good calibration curve with widely spread data points. These samples were scanned in the region of 1100 - 2500 nm in diffuse reflectance mode. An indigenous ELICO NIR spectrophotometer, modified according to the requirements of sugar industry was used for this purpose. Each sample was also analyzed simultaneously by standard chemical methods. Chemical values were taken as reference for near infrared analysis. In order to obtain the most accurate calibration for the set of samples, various mathematical treatments were employed. Partial Least Square method was found to be most suitable for the analysis. A comparison is made between the actual values (chemical values) and the predicted values (NIR values). The actual values agree very well with the predicted values showing the accuracy of the technique. The validity of the technique is checked by predicting the concentration of sugar in unknown molasses samples using the calibration curve. The present investigation assesses the feasibility of the technique for on-line monitoring of sugars present in molasses in sugar industries.

• 분석과학
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• 제8권2호
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• pp.181-186
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• 1995

저온처리로 자엽과 상배축(hypocotyl)에서 설탕의 농도와 환원당(reducing sugar)의 농도가 약간 증가되었다. 저온처리 동안 총 아미노산의 농도는 계속 증가되었다. 그러나 Asp/Asn, Glu/Gln Thr, Ser, Ala 등에 친수성 아미노산과 양전하를 가진 아미노산인 Lys과 Arg들은 저온처리 동안 계속 변화되었다. 이 변화는 단백질의 합성과 분해에 관계된다. 저온처리로 자엽에서는 24, 52, 55, 56과 73.5kD 단백질이 증가되었고, 줄기에서는 55, 56, 73.5kD 단백질이 증가되었다. 자엽과 줄기에서 유도된 24, 42, 49와 52kD 단백질들은 $100^{\circ}C$에서 끓여도 변성되지 않은 채로 남아 있어서 끓임에 강한 단백질들이다. 이 단백질들이 저온에 대한 저항력을 증가시키는 역할을 한다고 본다.

• 분석과학
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• 제9권4호
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• pp.325-330
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• 1996

몸무우의 자엽에 저온과 polyamine(PA)을 처리하면 세포내의 환원당과 설탕의 농도가 증가되었고, 가을무우의 자엽에 저온처리를 하면 환원당과 설탕의 농도가 증가되나, 저온과 PA를 동시에 처리하면 세포내에 당류의 농도가 증가되지 않았다. 몸무우 자엽에서는 저온처리에 의해 총 아미노산의 농도는 증가되나, 가을무우에서는 증가되지 않았다. 이 결과는 저온에 예민한 봄무우는 세포내의 삼투조절에 의하여 적응하며, 봄무우와 가을무우 사이에 생리 및 생화학적인 대사가 다름을 보여 주었다. 저온에 예민한 봄무우에서 PA는 저온처리와 함께 상승효과를 보이나, 저온 스트레스에 강한 가을무우에서는 PA 처리로 상승효과를 나타내지 못함은 처음 보고 하는 결과이다.

• 한국약용작물학회지
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• 제26권6호
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• pp.482-489
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• 2018

Background: This study was carried out to determine the physicochemical components of Rehmannia glutinosa (RG) fermented with Rhizopus delemar. Methods and Results: Physicochemical components such as changes in moisture content, pH value, total acidity, amount of reducing sugars as well as quantity of free sugars, free amino acids, and catalpol were investigated. Result showed that, the moisture content ranged from 64.26 to 65.51%. The pH and total acidity of the fermented RG decreased significantly during fermentation. The reducing sugar content ranged from 0.10 to 1.34%. The most abundant main free sugars were identified as raffinose, xylose, glucose, fructose, and sucrose. The sucrose content in 80% ethanol and in water extracts increased during RG fermentation. In total, 26 free amino acids were detected, including seven essential amino acids. In addition, the quantity of free amino acids decreased significantly during fermentation. Finally, the catalpol content of the fermented RG was highest on the $2^{nd}$ day of fermentation at 2,028.67 mg/ 100 g. Conclusions: These results indicated that fermentation of Rhizopus delemar could be used to enhance biological activity, and that fermented RG could be used as a functional material and as an edible resource in food and functional materials industries.