• Korean journal of food and cookery science
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• v.26 no.5
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• pp.545-551
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• 2010

In this study, Sulgidduk samples were prepared with 0%, 3%, 5% and 7% yacon powder. Sulgidduk samples were then examined for quality characteristics such as moisture content, general components, color, texture profile analysis, sensory qualities, and sugar content, in order to determine the optimal ratio of yacon powder in the formulation. Regarding the general components of yacon Sulgidduk, the contents of crude protein and lipid decreased as the ratio of yacon powder increased. The L-value for color decreased, whereas a- and b-values increased. In the texture profile analysis, 7%-added yacon showed significantly lower hardness, whereas 7% yacon powder showed the highest values for cohesiveness, springiness, and chewiness. The contents of sucrose, fructose, and glucose in yacon Sulgidduk were found to be 3%, 5%, and 7% by LC, respectively. Sucrose showed a decreasing trend with increased yacon powder content, but fructose and glucose increased with increased amount of yacon powder. For sensory qualities, taste/flavor, texture, hardness, and overall acceptability were not significantly different among the 0%, 3%, and 5% yacon powder samples.

• Korean Journal of Food Science and Technology
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• v.12 no.2
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• pp.88-96
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• 1980

Reaction conditions in the amino-carbonyl reaction, and the effect of amino acids on the reactivity of amino-carbonyl reaction were investigated. Results obtained are as follows : 1. When the pH of the reaction mixture was increased above the isoelectric point of an amino acid, a significant increase in the color intensity was observed. 2. The color intensity increased gradually up to 1 : 1 of the molar ratio of reactants. This result was interpreted to show that sugar and free amino group combined in 1 : 1 ratio. 3. Amino-carbonyl reaction showed a significant time and temperature-dependences. The activation energy at 0.2 M glucose and 0.2 M glycine system was 37.5 Kcal/mole. 4. Among amino acids tested, glycine, lysine and $\beta$-alanine caused a significant increase in the color intensity, but acidic amino acids showed the least color intensity. The latter was interpreted to show that one of carboxyl groups of acidic amino acid has an inhibiting effect on the reactivity of the amino group. 5. The color intensity of sugars tested was in the order of xylose>arabibose>fructose>glucose>maltose>lactose.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.442-446
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• 1985

The changes of nitrogen utilization ratio (NUR), Protein solution ratio (PSR) and free sugar contents during the amino acid soysauce manufacturing process by a low hydrochloric acid, temperature were investigated. On hydrolysis by 6%-HCI (3 liquor rate of defatted soybean weight, 3LR) at $85^{\circ}C$, NUR and PSR were 74.51%, 56.49% at 65 hours. At the same time free sugars were detected glucose, galactose, arabinose, fructose, xylose. on hydrolysis at $95^{\circ}C$, NUR and PSR were 77.72%, 64.04% at 50 hours, and 5 free sugars of the above statement were detected at 5 hours. Remarkable decreases in the levels of free sugars, only glucose were observed after 80 hours of the hydrolysis. On hydrolysis by 12%-HCI(3LR) at $95^{\circ}C$, NUR and IRA were 88.41%, 69.47% at 50 hours, free sugar were nearly disappeared after 20-35hours. On hydrolysis, galactose's disappearence rate was faster than glucose's.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.3103-3108
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• 2011

This work was aimed to evaluate supplementation of honey as sole carbon source on the fermentation characteristics of wine fermented with fruit of flowering cherry and honey(flowering cherry-honey wine). Physiochemical changes of flowering cherry-honey wine(2 L) were investigated during 30 days in fermentation by strain of Saccharomyces bayanus (EC-118). At the beginning of fermentation, fructose was most abundant sugar then glucose and sucrose were followed. As fermentation proceeded, utilization of glucose by S. bayanus (EC-118) was faster than fructose, so that the ratio of fructose/glucose was increased. During fermentation for 30 days, pH and viable yeast count was changed rapidly between 0 to 5 days, while $^{\circ}Brix$(%) decreased gradually for 30 days. Final total titratable acidity, pH, $^{\circ}Brix$(%) and ethanol content of flowering cherry-honey wine were 0.43%, pH 3.5, $9.7^{\circ}Brix$(%) and 14%, respectively. Our finding demonstrate that flowering cherry-honey could be benefical supplements for wine production.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.117-120
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• 1996

To enhance cellulose hydrolysis f Humicola insolens cellulase (HIC) was empolyed with immobilized glucose isomerase(IGI). Optimun pH and temperature for HIC were 6.5 and 55$^{\circ}C$, respectively, whereas those for IGI were 7.0 and 60$^{\circ}C$, respectively. Optimun loading size of IGI was 200mg(130 untis) with 15units of HIC. Reaction conditions were determined to be as follows: 55$^{\circ}C$,pH 6.5, HIC 15 units and IGI 130 units. After 24h hydrolysis, more than 65% of avicel was converted to glucose and fructose; in contrast, the conversion ratio of control was 40%.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.404-407
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• 1996

The effects of carbon sources on vancomycin production were investigated using Nocardia orientalis CSVC 3300. Among carbon sources tested, glucose, maltose and fructose were effective for the production of vancomycin. Glucose was favored for growth, but decrease the production of vancomycin at the concentration above 7.5%. In comparison, maltose did not decrease the production of vancomycin up to the concentration of 20%. When the mixture of glucose and maltose was used in the ratio 1:3 to 1:4, the highest production of vancomycin was achieved. When glucose concentration was set at 3.0%, catabolite repression could not be observed up to total sugar concentration of 16.0%. Fermentation was carried out using commercial hydrolyzed starch composed of glucose, maltose, maltotriose and maltotetraose, The initial glucose concentration was set at 3.0% and subsequent oligosaccharide consumption was monitored by checking their supernatant with HPLC. During initial cultivation for 38 hour, glucose was the sole carbon source leading to rapid growth. After cell growth stopped, the maltose and glucose concentrations increased due to degradation of maltotriose and maltotetraose, but glucose level was maintained at around 3.0%. After 70 hour fermentation, maltose slowly converted to glucose, and vancomycin production continued during the period.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1182-1189
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• 2008

Changes of free sugar on Gugija-sugar leaching were investigated by adding sugar on Gugija (Lycii fructus) raw fruit. Gugija were prepared by parboiling ($40{\sim}50$ sec at hot water of $85^{\circ}C$) and unparboiling. Gugija-sugar leaching were leached after preserving (5 and 10 months at $5^{\circ}C$) Gugija-sugar mixture (ratio of raw Gugija and sugar, 1:0.2, 1:0.4, 1:0.6, 1:0.8, and 1:1/w:w). Soluble starch content of Gugija-sugar leaching increased with increasing ratio of sugar without reference to parboiling treatment, having the highest content, 2.5% at UPRGSL-4 (unparboiling Gugija:sugar, 1:0.8 leaching). Maltose content increased with increasing ratio of sugar in PRGSL, being the highest at 12.66% in PRGSL-5 (parboiling Gugija:sugar, 1:1 leaching) at 10 months leaching periods. Most of the sucrose went out of existence with increasing leaching periods; content was 4.22% on PRGSL-5 and 1.36% on UPRGSL-5. Content of glucose and fructose increased with increasing ratio of sugar; glucose content was 7.86% on PRGSL-4 and 26.22% on UPRGSL-5, at 10 months leaching periods. Fructose content was 18.46% on PRGSL-5 and 22.51% on UPRGSL-4 at 10 months leaching periods. Contents of sorbitol and glycerol increased with increasing ratios of sugar.

• The Korean Journal of Mycology
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• v.9 no.1
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• pp.19-24
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• 1981

The mycelial growth of Agaricus bitorquis and Pleurotus ostreatus in synthetic media were carried out by ordinary methods. The optimum pH and temperature for mycelial growth were from pH 6.0 to 6.5 and 25 to $30^{\circ}C$, and from pH 5.0 to 6.5 and $25^{\circ}C$ in A. bitorquis and P. ostreatus, respectively. Among the carbon and nitrogen sources, glucose, starch, and peptone showed the good result for the mycelial growth of A. bitorquis, and glucose, fructose, starch and peptone were good for the mycelial growth of P. ostreatus. The yield of mycelium decreased under lower or higher C/N ratio. Also, at the same C/N ratio, the higher the concentration of glucose and peptone, the more the yield was increased. Among various vitamins thiamine, Ca-pantothenate and folic acid were suitable for the mycelial growth of A. bitorquis, and thiamine, folic acid and ino­sitol for the mycelial growth of P. ostreatus. Although pH, total nitrogen and glucose contents of media decreased gradually during culture period the yield of mycelium increased.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.631-636
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• 1988

Quality of five kinds of honey, from acacia, bush clover, chestnut, rape and polyflower sources, were evaluated by physicochemical methods in respect to some chemical constituents. The average values for the tested honeys were: moisture, 19.5%; fructose, 33.74% , glucose. 35.03%; sucrose, 4.67%; hydroxymethylfurfural, 6.17mg,/kg; total nitrogen, 0.027%, proline, 23.67mg%; lactone, 4.09meq/kg; free acidity, 11.37meq /kg; and total acidity, 15.46meq/kg.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.370-374
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• 1997

Commercial Sikhye was fermented by Saccharomyces cerevisiae for 10 day at 29$^{\circ}C$. Sucrose was hydrolyzed into glucose and fructose by invertase from the yeast, and the glucose and fructose were converted into ethanol by the yeast. Commercial Sikhye wine was found to contain 6.6% of ethanol, 0.32$\mu$mol/ml of amino acid, 226$\mu\textrm{g}$/ml of protein, and 2.5ml 0.1N NaOH of acidity, respectively, and its pH was 3.21. Limit dextrin in commercial rice Sikhye wine showed both signal of $\alpha$-1, 4- and $\alpha$-1, 6- glucosidic linkage with its estimation ratio of 25:1 by 1H-NMR analysis. The taste of rice Sikhye wine was similar that of wine.