• Food Science and Biotechnology
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• v.17 no.5
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• pp.931-939
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• 2008

The objective of this study was to investigate the enolization reaction and the antioxidant activity of caramelization products (CPs) obtained by caramelization browning of glucose and fructose solutions prepared at a pH ranging from 7.0 to 12.0 at varying temperatures ($80-180^{\circ}C$). The degradation of sugars rapidly increased at a high alkaline pH (10.0-12.0), and fructose degraded more rapidly than glucose (p<0.05). As the pH increased, the degree of sugar enolization was higher in fructose than in glucose. Browning and the formation of intermediate degradation products increased with the increase in heating temperatures. The browning development was dependent upon the type of sugar, and it was generally higher at alkaline pH than at neutral pH. The reducing power and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of the CPs increased with the increase in browning and formation of large amounts of intermediates. Therefore, the CPs with pronounced antioxidant activity can be prepared by heating fructose or glucose solutions that have a very alkaline pH to high temperatures.

• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1368-1376
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• 2014

This article focuses on the effects of glycine betaine on preventing caramelization, and increasing DCW and $\small{L}$-lysine production. The additional glycine betaine not only decreased the browning intensity (decreased 4 times), and the concentrations of 5-hydroxymethylfurfural (decreased 7.8 times) and furfural (decreased 12 times), but also increased the availability of glucose (increased 17.5%) for $\small{L}$-lysine production. The DCW and $\small{L}$-lysine production were increased by adding no more than 20 mM glycine betaine, whereas the DCW and $\small{L}$-lysine production were decreased with the reduction of pH values, although pH had a better response to prevent caramelization than did glycine betaine. For $\small{L}$-lysine production, the highest increase (40%) was observed on the media with 20 mM glycine betaine. The crucial enzymes in glycolysis and $\small{L}$-lysine biosynthesis pathway were investigated. The results indicated that additional glycine betaine increases the activity of enzymes in glycolysis, in contrast to the effect of pH. All the results indicated that glycine betaine can be used to prevent caramelization and increase the $\small{L}$-lysine production. By applying this strategy, glucose would not be have to be separated from the culture media during autoclaving so that factories can save production costs and shorten the fermentation period.

• Korean Journal of Food Science and Technology
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• v.7 no.1
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• pp.43-50
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• 1975

The antioxidant effects of the alcohol extracts obtained from a Maillard-type and a caramelization-type browning reaction mixtures were determined and compared. The Maillard-type reaction mixtrue contained 0. 2 M glucose and 0. 2 M glycine while the caramelization-type reaction mixture contained only 0. 2 M glucose and both were heated at $100^{\circ}C$. The results obtained are as follows. 1. The color intensity of the Maillard-type reaction mixture appeared to increase in proportion to the length of reaction time. However, the antioxidant activity of the extracts did not seem to increase in proportion to the length of reaction time. The antioxidant activity of the extracts from the reaction mixture heated for 16 hours was not much greater than that of the extracts from reaction mixture heated for 2 hours. 2. The color intensity of the caramelization-type browning reaction appeared to increase in proportion to the length of reaction time. The antioxdant activity of the extracts did not seem to increase in proportion to the length of reaction time. 3. It appeared that the antioxdant effects of the alcohol extracts from the Maillard-type browning reaction mixture were far greater than those from the caramelization-type browning reaction mixture, compared on the basis of the same length of reaction time. Substrates, containing the alcohol extracts of the caramelization reaction mixture taken after 4 and 120 hours, developed peroxide values of 88. 9 and 33. 0 after a 20 day storage period (control, 135. 0) whereas substrates, containing the alcohol extracts of the Maillard-type reaction mixture taken after 1 and 16 hours, developed peroxide value of 9. 5 and 7. 5 after the same storage period.

• Applied Biological Chemistry
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• v.42 no.2
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• pp.152-155
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• 1999

Effects of pH, amino acids, hydrolyzed protein and potassium phosphate on caramelization were investigated for improvement of its reaction rate. The caramelization was performed with starch syrup at $110^{\circ}C$ and the different color functions-metric saturation(Suv), 5-hydroxymethylfurfural (HMF) contents and absorbance at 420 nm were measured. As the pH was raised from 4 to 10, the reaction rate (Suv/hr) was increased by 31.9% along with significant increase in HMF content and absorbances at 420 nm. Among the several amino acids, arginine and glycine were very effective for improvement of caramelization, which may be due to Maillard reaction. When $K_2HPO_4$ were added in different ratio with arginine, glycine, HVP or HAP, the effects of arginine and HAP on thee rate were markedly enhanced while the effects of glycine and HVP were rather reduced.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 1995.11a
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• pp.440-440
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• 1995

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.983-987
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• 1998

Effects of sugars, temperature, pH and some chemicals on caramelization were investigated for improving of its reaction rates. Among the sugars tested, fructose showed the fastest reaction rate, followed by sucrose, glucose, starch syrup and maltose. As the reaction temperature increased from 80 to $110^{\circ}C$, the rate greatly increased by the range of $150{\sim}8000$ folds depending on sugars. It was indicated that pH 10 resulted in the highest reaction rate in the range of $pH{\;}4{\sim}10$. When several chemicals, such as phosphates and organic acid salts, were added to starch syrup, the rate increased by more than 10 folds, in particular effects of $K_2HPO_4$ and sodium salts of citrate, oxalate and succinate were significant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1041-1046
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• 2001

Solutions of fructose, glucose and sucrose were heated without catalyst at various temperature for different length of time. Changes in the formation of early caramelization product and browning intensity as well as pH of heated sugar solutions were determined. Reducing powers of caramelization products (CP) and their inhibitory effects on polyphenol oxidase (PPO) were also determined and their correlations were discussed. The early CP and browning intensity increased with temperature and time, in the order of heated fructose>sucrose>glucose solutions (p<0.005), while pH decreased. pHs of sugar solutions heated at 20$0^{\circ}C$ showed in the range of 3.32 ~ 3.50. Reducing power of CP as well as their inhibitory effect on PPO also increased with temperature and time, respectively. Among sugar solutions, reducing power showed the same trends as above at both 15$0^{\circ}C$ and 17$0^{\circ}C$ (p<0.001). However, those of heated fructose solutions were the highest in the early stage, while those of heated sucrose solutions were the highest in the final stage at 20$0^{\circ}C$. This is due to the difference in CP formed. Sucrose solution heated at 20$0^{\circ}C$ showed the highest inhibitory effect, reducing PPO activity by 34.6%. From these results, it is considered that the inhibitory effect of CP on PPO is partly related to their reducing power.

• Korean journal of food and cookery science
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• v.18 no.6
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• pp.603-612
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• 2002

The study was carried out to compare the relation between the color intensity and antioxidant activity of caramelization products using xylose(XY), glucose(GL). sucrose(SU), glucose＋citric acid(GLCA), glucose＋sodium citrate(GLSC), heated at 80, 120 and 140$\^{C}$ for 24hrs, respectively. The color intensity(absorbance at 490nm) of the browning mixtures increased as the browning temperature and time increased. But the degrees of color intensity of SU and GLCA changed very little. The hydrogen donating ability(HDA) of browning reaction products was generally enhanced as the browning temperature and time increased. When browning mixtures were heated at 80$\^{C}$, the HDA of GLGC was the highest, but the HDA of GLSC was the highest when heated at 120 and 140$\^{C}$. The antioxidant activities for the corn oil substrate containing the anhydrous ethanol extracts from the browning mixtures was inferior to that of SU, but was superior to that of GLCA. The relations among the color intensity, the antioxidant activity, and the hydrogen donating ability(HDA, reducing power) of the browning reaction mixtures were as follows: As the color intensity increased, the antioxidant activity decreased. The correlation coefficient of the color intensity and the antioxidant activity by regression equation was -0.73 ∼ -0.82. As the reducing power increased, the antioxidant activity decreased. The correlation coefficient between the reducing power and the antioxidant activity by regression equation was -0.98 ∼ -0.99. Therefore, the antioxidant activity of browning reaction mixtures seemed not correlated with the color intensity and the reducing power.

• Korean journal of food and cookery science
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• v.11 no.4
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• pp.396-400
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• 1995

The antioxidant effects in soybean oil was investigated by browning reaction mixtures formed by sugar and reaction temperatures above 110$^{\circ}C$. 0.1 M solution of xylose, glucose and sucrose were heated at 110, 120, 130, 140 and 150$^{\circ}C$ for 24 hrs respectively. A reaction rate constant(k), activation energy (Ea) and Q$\sub$10/ value were determined by color intensity that was measured absorbance at 490 nm in each temperature. Soybean oil containing the ethanol extracts taken from the browning reaction mixtures that were heated at 110, 130 and 150$^{\circ}C$ was stored in an incubator kept at 45.0${\pm}$1.0$^{\circ}C$ for 24 days. The results are as follows: 1. When 0.1 M solution of xylose, glucose and sucrose were heated at 110$^{\circ}C$ and 120$^{\circ}C$, the intensity of glucose browning mixtures was the highest, but heated at 150$^{\circ}C$, the color intensity increased in order of xylose > glucose > sucrose after 24 hrs. 2. The reaction rate constant (k) was increased rapidly above 140$^{\circ}C$ and appeared maximum at 150$^{\circ}C$, esp. xylose was the highest. The activation onergy (Ea) of xylose was the highest as 93.28 Joule/mole and the Q$\sub$10/ value of xylose was appeared 1.28. Q$\sub$10/ value was also the highest in xylose. 3. The browning reaction mixtures that were heated at 110$^{\circ}C$ appeared little antioxidant effects. But, in heated at 130$^{\circ}C$ and 150$^{\circ}C$, the antioxidant effects appeared in sucrose browning reaction mixtures. Therefore, in browning reaction mixtures that heated above 110$^{\circ}C$, only sucrose browning reaction mixtures appeared antioxidant effects and xylose, glucose appeared little antioxidant effects. On the contrary xylose and glucose increased peroxide values of soybean oil.

• Food Quality and Culture
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• v.2 no.1
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• pp.37-42
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• 2008

This research examined the quality characteristics of orange sauce samples prepared with different sugar contents in order to create a standardized recipe.In the foodservice industry, attempts have been made to make superior sauces, often resulting in error. In this study, different sugar contents were examined for orange sauce to determine why varied results occur during its preparation as well as the best methodology for preparing orange sauce. Quality characteristics such as color differences, spreadability, and pH were analyzed, as well as sensory evaluations of taste, texture, color and overall acceptability. The pH values of the orange sauce samples ranged from 3.6 to 3.63 and after the initial simmering of ingredients, the weight reduction rates of the sauces were 88, 75, 64, 63, and 64% for sugar contents of 200, 300, 400, 500, and 600 g respectively. Hunter's color L, a, and b values of the samples changed according to the sugar contents after simmering (1st sauce). The L and b values showed similar patterns, where increasing sugar content resulted in higher values; however, in the 2nd sauce, the pattern was reversed. This indicates that the color of the sauce was affected by sugar caramelization during the reduction process; however, the final color was modified by the additions of mayonnaise and butter as well as by aeration. In the sensory evaluation the sample containing 30% sugar (500 g) had significantly higher acceptability scores (p<0.05) for color, mouth feel, appearance, taste, and overall acceptability. Finally, the optimal ingredient ratios of the standardized orange sauce recipe were determine as: 48% total liquid consisting of orange juice and mandarin and orange fruit; 30% sugar; 10% mayonnaise and 11% butter.