• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.55-60
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• 1986

The effects of temperature (70-$100^{\circ}C$), pH (3-8) and various sugars were investigated on the reaction rate, activation energy and z-value of Maillard reaction of 0.8m sugar and 0.8m glycine mixture. The sugars compared were glucose, fructose, lactose and sucrose, and the reaction was evaluated by absorbances at 278nm for pyrazine compounds and at 400nm for brown pigments. Fructose-glycine mixture showed a faster initial reaction rate than that of glucose-glycine, which was reversed by the order of glucose > fructose > lactose > sucrose after 10 hrs of reaction at pH 5.8 and $100^{\circ}C$. Generally, higher activation energy was required for forming pyrazines than that of brown pigment development. The highest z-value was obtained for lactose-glycine mixture, followed by glucose or fructose-glycine which had almost same z-value. The reaction rate was little affected by the pH change in the range of 4-6, while pH < 3 and pH 6-8 caused a significant increase in the rates.

• The Korean Journal of Food And Nutrition
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• v.6 no.4
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• pp.268-275
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• 1993

The whole cells of Actinoplanes missouriensis KCTC 1780 which produce glucose isomerase was immobillized by flocculation method for the effective production of high fructose syrup using packed-bed bioreactor system. Among the flocculation methods used In this study, the glucose Isomerase activity of flocculated cells using 5% polyethylenimmine and 0.2% glutaraldehyde was the highest as 46.3 unit, and the flocculant was 10.3g(wet weight) per 100m1 of broth, and the residual activity was 92.5%. In the batch operation of glucose isomerization using the flocculated cells, the optimum pH, temperature and isomerization ratio were 7.0, 75$^{\circ}C$ and 31%, respectively. The optimum concentration of Mg2+ which was activator on the glucose isomerization of flocculated cells was 0.1M, and glucose isomerase activity was increased by about 40% compared to none of Mg2+. In the packed-bed bioreactor system with 1.2 hour of residence time at 7$0^{\circ}C$, the reaction stability maintained until 96 hour without toss of activity, and the equilibrium was kept up to 120 hours of the operation.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.129-135
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• 1988

The changes of sugar content and invertase activity during maturation of plum fruits, and properties of the enzyme were investigated in this study. The soluble sugars in plum fruits were mainly sucrose, glucose and fructose. The sucrose content in the fruit increased slowly at the early stage of maturation and then decreased slightly. At the final stage, the sucrose content increased remarkably with maturation. The contents of glucose and fructose increased slowly at the early stage of maturation following decrement at middle stage. At the final stage, glucose content decreased continuously while fructose content increased again following decrement. Invertase activity in the fruit increased during maturation showing maximum at the onset of color change and after that, decreased remarkably. The optimum pH and temperature of invertase activity were pH 5.0 and $65^{\circ}C$, respectively. The enzyme was most stable at pH 5.0 and retained 75% of its activity after incubation at $70^{\circ}C$ for 15min. The enzyme was activated by $Cu^{{+}{+}}$, $Ca^{{+}{+}}$, but inhibited by $Hg^{{+}{+}}$ remarkably.

• Journal of Plant Biotechnology
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• v.31 no.2
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• pp.169-173
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• 2004

Parenchyma cells of Streptanthus tortus suspension cultures possessed the different transport system for aldose-formed D-glucose and for ketose-formed D-fructose. $K_{m}$ value for D-glucose and D-fructose were 0.28mM and 15.02mM, respectively. $K_{m}$ value of D-mannose was 0.44 mM which is similar to the D-glucose transport system, but D-mannose was transported also through its own special uptake system. Parenchyma cells possessed the transport system of L-glucose, but the function of L-glucose was not known at all. Protoplast of parenchyma cells possessed only the monosugars transport system, but didn't possess the disugars, sucrose transport system. Early developing phloem protoplasts possessed glucose and sucrose transport system at the same time. On the contrary, in the complete developed phloem cells disappeared preexisted glucose transport system in the parenchyma cells, only new induced sucrose transport system existed.ted.

• Journal of Dairy Science and Biotechnology
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• v.35 no.2
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• pp.99-104
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• 2017

The global consumption of fructose in the form of high-fructose corn syrup (HFCS) has increased considerably over the past several decades. The current intake of HFCS exceeds that of other major caloric sweeteners such as sucrose. Fructose has potentially adverse effects on human metabolism. Therefore, the objective of this study was to analyze the monosaccharide contents of 13 sweetened milk-based beverages by using high-performance liquid chromatography (HPLC). The total monosaccharide (fructose and glucose) contents of various sweetened milk-based beverages ranged from 0.60 g/100 mL (cheese) to 26.03 g/100 mL (maple caramel snack), while milk showed only 0 g/100 mL monosaccharides. The fructose-to-glucose ratio of various popular sweetened milk-based beverages ranged from not-detected (ND) to 2.24 g/100 mL, but the content of glucose was higher than that of fructose in only three samples, namely, strawberry flavored milk, shrimp chips, and maple caramel snack. The analyzed results revealed important basic information about monosaccharides in various milk-based sweetened beverages, presenting ideas for future fructose research.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.322-327
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• 1995

Experiments were conducted to know the relationships between seed quality and leakage of sugars from differently-aged seeds of rape, Chinese cabbage and radish. Seeds were artificially aged at 90% relative humidity and 45$^{\circ}C$ to get different seed qualities. Significant amounts of total sugars were leaked from the dead seeds of all crops during the 8~24 hours soaking period, while high quality seeds leaked negligible amounts of total sugars. High quality seeds of all crops contained lots of sucrose and glucose and some stachyose, raffinose and fructose. During the artificial aging of seeds stachyose, raffinose, and sucrose decreased, while glucose and fructose increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.7
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• pp.999-1004
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• 2010

This study was carried out to investigate the quality characteristics of ginseng Jung Kwa obtained by treatments with different sugars. Ginseng Jung Kwa was made with four different sugars (sucrose, glucose, honey and fructose). Chemical characteristic was measured by ginsenosides content and rheological characteristics were measured by rheometer and color meter. Total ginsenoside and Rf contents on Ginseng Jung Kwa by sucrose were highest at 10.0, and 7.82 mg/g, respectively. On ginseng Jung Kwa by fructose, total ginsenoside content was the lowest, and hardness and adhesiveness were the highest, and by honey, stiffness, cohesiveness, gumminess, chewiness, and springiness were the highest, and fracture force did not appear as a significant difference by treatment of different sugars. Coefficient of variance on ginseng Jung Kwa by honey was the highest. On ginseng Jung Kwa by sucrose, color (lightness, redness and yellowness) all were the highest. Browning on Jung Kwa by fructose was the greatest. Sensory evaluation preference analysis (color, taste, texture, flavor and overall acceptability) on ginseng Jung Kwa were determined by 50 panelists (30~50's age) using 5-point scale. On ginseng Jung Kwa by honey, texture and overall acceptability were the best. Ginseng Jung Kwa by fructose was very sticking and adhering, so preference by sensory evaluation was inferior to others.

• Journal of the Korean Society of Food Culture
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• v.3 no.4
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• pp.385-390
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• 1988

This study was conducted to determine the interconversion of sugars in persimmon during the drying process and the textural properties of raw and dried persimmons using the changes of some chemical constituents, the analysis of sugar component, and the measurement of texture. Five varieties of persimmons were used in this experimment. As the drying proceeded, content of acetaldehyde and alcohol increased while soluble tannin content rapidly decreased. The rapid changes of these component obserbed in kyongsan Bansi and Hiratanenashi. Soluble sugars detected in raw persimmons were mainly glucose, fructose and sucrose. The content of sucrose was rapidly decreased in early stage of drying, while glucose and fructose were rapidly increased. The nearly same amount of glucose and fructose presented in the dried persimmon although there were some differences among varieties tested. The major component of white powder developed on the surface of dried persimmon was almost glucose. The texture profile analysis of the raw and dried persimmons was made with texturemeter and the quality of the dried persimmons was sensory evaluation method. Hiratanenashi and Sagoksi were determined as the suitable varieties in the processing of dried persimmons, but the varieties of Changdungyee and Namyang Susi were not suitable.

• Preventive Nutrition and Food Science
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• v.13 no.2
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• pp.134-137
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• 2008

This study was conducted to investigate the effect of pH on the formation of acrylamide and acrylate from glucose and fructose reacting with amino acid enantiomers by the Maillard reaction. The acrylamide content was increased with increasing pH, except for Fru/D-Asn system. Both acrylamide and acrylate contents were higher in the glucose-based system compared to the fructose-based system at pH 10.0. However, according to amino acid enantiomers, only the acrylamide content showed a difference in the fructose-based system. In addition, the acrylate content was increased with increasing pH except in the Glc/L-Asn system. Acrylate formation was observed specifically at pH 4.0 for both the Glc/D-Asn and Fru/D-Asn systems.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.273-277
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• 1979

Free sugars in various ginseng products, Korean and Russian Acanthopanaxes were analyzed by gas liquid chromatography. Ginseng products included Korean red ginseng, white ginseng with skin produced in Korea, Canada, and America, and extracts of red and white ginseng. ${\alpha}-\;and\;{\beta}-fructoses,\;{\alpha}-\;and\;{\beta}-glucoses$, galactose, sucrose, and ${\alpha}-\;and\;{\beta}-maltoses$ were identified in Korean and American white ginsengs with skin, and in Korean red ginseng. However ${\alpha}-\;and\;{\beta}-maltoses$ were not detected in Canadian white ginseng with skin. Total amount of sugars identified in white ginseng with skin was higher than that in red ginseng. ${\alpha}-\;and\;{\beta}-fructoses,\;{\alpha}-\;and\;{\beta}-glucoses$, galactose, sucrose and ${\alpha}-\;and\;{\beta}-maltoses$ were identified in red and white ginseng extracts. Fructose was a major sugar in red ginseng extract while it was sucrose in white ginseng extract. ${\alpha}-\;and\;{\beta}-glucoses$, galactose, sucrose and ${\alpha}-\;and\;{\beta}-maltoses$ were identified in Russian Acanthopanax, and their patterns were similar to that of ginseng, while ${\beta}-fructose,\;{\alpha}-\;and\;{\beta}-glucoses$ and sucrose were identified in Korean Acantopanax and total amount of sugars was only one third of that in Russian Acanthopanax.