• Korean journal of food and cookery science
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• v.10 no.1
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• pp.39-44
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• 1994

For the purpose of supplying the basic knowledge to make Doenjang which is acceptable to Korean people three kinds of koji, namely rice, wheat, and soybean Koji were made with Aspegillus oryzae. Then Doenjangs were made with four different ratio of three Kinds of Koji. Components related to the taste of Boenjang were analyzed, sensory evaluation of Doenjang were made, and correlation between analytical variables and sensory parameters were investigated. The results were as followed 1. Total nitrogen contents of each Doenjang were increased with increasing the ratio of Koji except Doenjang made with soybean Koji. The amounts of amino nitrogen increased with the ratio of koji increases in each Doenjang. Amino nitrogen contents of Doenjang made with soybean Koji were highe. than the others, 2. Reducing sugar contents of rice and wheat Doenjang were similar, but amounts were increased with increasing the ratio of Koji Reducing sugar contents of Soybean Doenjang were lower than the others. pH of the Doenjangs decreased as the ratio of the koji increased. The amount of sweet taste amino acids and MSf; like amino acids were increased, but bitter taste amino acids were decreased as the ratio of the koji increased in rice and wheat Doeujang, The sweet taste amino acids and bitter taste amino acids in soybean Doenjang showed little Changes in amount, but the amount of MSG like amino acids increased as the ratio of the Koji increased from 13% to 25%, 37%, and 50%. The nucleotide contents of wheat Doenjang were higher than other Doenjangs, and there is a tendency to increase the amounts of nucleotide as increasing the ratio of koji in each Doenjang. 3. As a result of sensory evaluation, wheat Doenjang of 13% koji ranked highest in the overall eating quality, and Doenjangs made with 50% and 37% of rice koji ranked next, 4. pH and sweet tast amino acids influenced on the Overall eating quality of the Doenjang, however most compo-nents of the Doenjang seemed to relate to overall eating quality of Doenjang, however most components of the Doenjang seemed to relate to overall eating quality of Doenjang.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.898-904
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• 2003

This study was conducted to observe the effect of various kinds of sugars and their molar concentrations on the Maillard browning reaction. To observe the effects of various kinds of sugar, glucose, fructose, tagatose, xylose, and sucrose were employed. A model solution consisting of 0.2 M sugar and 0.2 M glycine was prepared and heated at $100^{\circ}C$ for 5 hr. The model solution with adjusted concentrations of either tagatose or glycine was also heated at $100^{\circ}C$ for 5 hr. Tagatose showed the fastest Maillard reaction, followed by xylose, fructose, glucose, and sucrose. After glycine concentration of the model solution was fixed, the model solution showed more browning with an increase in tagatose concentration. When the tagatose concentration of the model solution was fixed, the model solution showed more browning with an increase in glycine concentration. The model solution with a fixed concentration of glycine showed more more browning than that with a fixed concentration of tagatose, since the former had higher amounts of the reactant.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.324-330
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• 1994

This study was conducted to examine the effects of the kinds and the levels of salted and fermented seafoods, shrimp and juice of anchovy, on the properties of kimchi during fermentation. There were no significant differences in pH and contents of total acid, reducing sugar, and organic acid examined except lactic acid contents among the kimchi samples at the same fermentation period. Until four days of fermentation, kimchi containing higher level of salted and fermented anchovy juice tended to have greater number of total microorganisms and of Leuconostoc genus microorganisms than the other kimchi samples. Sensory characteristics were not significantly different among the samples at the same fermentation period. significant decrease in pH and in reducing sugar content, and increase in total acid content were noticed in all the kimchi samples during fermentation. This was more marked in kimchi samples containg salted and fermented seafoods. Contents of malic and succinic acids decreased while those of actic and acetic acids increased with longer fermentation. There were significant changes in the numbers of microorganisms during fermentation. Carbonic mouthfeel, salty taste, sour taste and staled flay or of all the kimchi samples increased while firmness and crispness decreased with extended fermentation.

• Food Science and Preservation
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• v.18 no.6
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• pp.884-890
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• 2011

In this study, the quality characteristics of eight kinds of non-sterilized commercial makgeolli were investigated. The alcohol contents of five kinds of makgeolli were determined to be as follows: 5.7~5.8%, G $6.7{\pm}0.1%$, D $6.8{\pm}0.2%$, and C $7.5{\pm}0.1%$. As for the titratable acidity, makgeolli C and D showed higher than 0.5%, H showed $0.49{\pm}0.02%$, and the rest showed 0.45% or less. For the pH levels, there were no significant differences among the samples. The reducing-sugar content was approximately 200 mg%, and those of makgeolli A and F were lower by approximately 90 mg%. As for the organic acids, malic acid was detected only in makgeolli A and G while the acetic-acid content was high in makgeolli C and D. Concerning free sugars, fructose and sucrose were not detected, and the glucose content of makgeolli G was shown to be the highest ($335.1{\pm}40.3$ mg%). The maltose contents were similar ($23.5{\pm}1.0{\sim}45.0{\pm}1.1$ mg%), except for makgeolli G, whose maltose content was $73.5{\pm}1.8$ mg%. For the alcoholic ingredients, 0.4~0.5 mg/mL 1-propanol, 2-methyl-1-propanol, and iso-amylalcohol were detected, a suitable table wine standard. Further studies involving the quality analysis of the leavening agents, fermentation conditions, and fermentation types are needed.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1570-1576
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• 1999

Quality characteristics of 3 kinds of kochujang were investigated during 6 months of fermentation in order to improve the quality of industrial kochujang to that of traditional one. Three different kinds of kochujang were prepared using Aspergillus oryzae, Aspergillus oryzae plus Bacillus licheniformis and Aspergillus oryzae, Bacillus licheniformis plus Saccharomyces rouxii. Kochujang prepared with all three microorganisms contained lesser amounts of free sugar than the other preparations and glucose was the most abundant free sugar found. Ethanol was the most abundant amount among alcohols in kochujang. Kochujang prepared with A. oryzae, B. licheniformis plus S. rouxii has more amino nitrogen content than that prepared with A. oryzae only. Capsaicin contents of kochujang decreased slightly in all three kochujang, but there was no significant differences. The results of sensory evaluation showed statistically significant difference among three samples and panel members preferred the taste and flavor of kochujang prepared with all three microorganisms to those of the other samples.

• Korean Journal of Microbiology
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• v.46 no.3
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• pp.308-312
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• 2010

Deinococcus geothermalis is a moderate thermophillic radiation resistant bacterium producing greater abundance of sugar metabolism enzymes than other Deinococcus species. In this study, optimal condition for xylanolytic activity of D. geothermalis was determined and xylooligosaccharides from oat spelt, beechwood, and birchwood xylan hydrolysates by this organism were analyzed through HPLC. Reducing sugar yield was increased in the order of beechwood, birchwood, and oat spelt xylan. D. geothermalis displayed maximal xylanolytic activity at $40^{\circ}C$ and pH 8.0. Magnesium ion increased xylanolytic activity upto 7.5 fold. Six kinds of xylooligosaccharides (xylose, xylobios, xylotriose, xylotetraose, xylopentaose, and xylohexalose) were detected from beechwood and birchwood xylan reaction products. Among them, xylose was the major product. However, only three kinds of xylooligosaccharides (xylose, xylopentaose, and xylohexalose) were clearly detected from oat spelt xylan. Gamma-ray (50 kGy) treatment of beechwood xylan, birchwood xylan and oat spelt xylan increased xylanolytic activity of D. geothermalis. The results indicate that D. geothermalis and pretreatment of radiation is useful for xylooligosaccharides production.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1472-1478
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• 2008

Four kinds of wild grape Yakju were fermented with wild grape and cereal such as rice, glutinous rice, barley or millet, and their quality characteristics were investigated. Reducing sugar, total sugar, and activities of $\alpha$- and $\beta$-amylase decreased until 2nd day, increased on 3rd day, and gradually decreased after 5 days of fermentation. Reducing sugar content was in the order of glutinous rice> barley> rice> millet group, and this was consistent with the result of $\beta$-amylase activity. Total sugar content was in the order of glutinous rice> rice> barley> millet group, and it was consistent with starch content of each cereal. Alcohol content decreased after 2 days, then glutinous rice group gradually increased from 3 days whereas other groups showed no difference from 5 days of fermentation. pH decreased until 2 days of fermentation, slightly increased and then showed almost no change after 5 days of fermentation. Total acid increased until 2 days, then decreased on 3rd day of fermentation, and gradually increased in the order of barley> millet> rice> glutinous rice group. L value was the highest in the initial day of fermentation, however it decreased with fermentation time. While a value was also the highest in the initial day of fermentation, it gradually decreased after slightly increasing in 3 days of fermentation. In contrast, b value was the lowest in the initial day of fermentation. It greatly increased until 3 days, then decreased on 5th day of fermentation and gradually increased again. Groups of rice and glutinous rice had more brown color than those of barley and millet. In the sensory evaluation, wild grape Yakju using rice was the most preferred in taste, flavor, and overall preference.

• Microbiology and Biotechnology Letters
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• v.39 no.1
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• pp.56-62
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• 2011

We investigated quality characteristics of Seoktanju (one of the Korean traditional rice wine) which was fermented using five kinds of Korean commercial Nuruks. The purpose of this study was to research what effects on the quality of Seoktanju by using different Nuruks. We analyzed general component such as each mash's temperature change patterns, pH, titrable acidities, reducing sugar contents, volatile acids, and sugar contents during fermentation periods and studied sensory evaluation of produced Seoktanju (10 days). On the whole, temperature change patterns in the each mashes were depend on room temperature. All Seoktanju's pH was reduced rapidly up to three days after first mashing (pH 3.13-3.57) and after that was increased gradually. The end of fermentation pH was pH 3.6-4.05. Mostly, acidities were indicated high(0.59%) and Nuruk-B was showed highest acid value. These results seems to be different as occasion organic acids producing activity depend on the number of yeast, material contents, optimal temperature in the each mashes by fungi and lactic acid bacteria in Nuruks. In reducing sugar contents and sugar contents, Nuruk-C treatment were showed the highest value with 5.36%, $23^{\circ}brix$, respectively and alcohol content was lowest with 8.6%. In the five kinds of reproduced Seoktanju, alcohol content was the highest in the treated Nuruk-A group. Volatile acid value was the highest with 132.6~263.7 ppm at the 3 day after first mashing day but as the fermentation time goes on, it was reduced sharply by 5.25~5.94 ppm. Sensory evaluation was performed with 5 point scale, the Seoktanju using Nuruk-D was presented by 4 point, while Nuruk-A was presented lowest by 2.77 point on overall acceptability.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.511-520
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• 2000

To investigate the effect of sugar and drying method on quality and storage characteristics of beef jerky, storage, textural and sensory characteristics were examined. Water activity was decreased as storage time was prolonged and the honey and rice syrup-added natural dried samples(N-H, N-R) were recorded the lowest value, 0.71 at five weeks of storage. During the storage period, pH values of all the samples were decreased and honey-added and heated air dried beef jerky(H-H) had the lowest pH value, 5.22. L, a, b values had a tendency to decrease, during the storage period. During the storage period, TBA values of all samples showed increasing tendency. Sugarsyrup-added samples(N-S, H-S, S-S$\^$*/) had the lowest TBA value, and those of honey-added samples(N-H, H-H, S-H$\^$**/) were highest, regardless of drying method. Total plate counts of bacteria and the number of lactic acid bacteria were increased as storage time was prolonged. Sugar syrup-added and heated air dried beef jerky(H-S) had the lowest in total plate counts of bacteria and the number of lactic acid bacteria, at five weeks of storage. Textural properties value of all samples were increased as storage time was longer. Honey-added samples showed the higest springness and cohesiveness value and sugarsyrup-added and natural dried sample showed the highest value in chewiness, gummness and hardness. In the almost sensory score of natural dried beef jerky was decreased asstorage time was prolonged, regardless of packaging method. The sensory score of heated air dried samples were higher than those of natural dried samples, regardless of packaging method. $\^$*/S-S sucrose syrup added smoking dried sample, $\^$**/S-H honey added smoking dried sample

• Korean Journal of Community Nutrition
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• v.12 no.2
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• pp.189-197
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• 2007

Low glycemic index (GI) foods have been reported to be very important in the control of blood glucose levels in diseases such as diabetes mellitus and obesity, which are becoming more prevalent in Korea. Bread consumption at breakfast and as a snack is also on the rise. To provide low GI alternatives, breads supplemented with dietary fibers-fructooligosaccharide (FOS), ground whole rye, and 2 types of resistance starch (RS2 and RS4)-were developed. The GIs for these breads were evaluated with 13 healthy college students (M6, F7) and sensory tests were done. Four kinds of breads were made through the modification of a basic recipe for white bread (the control, B) as follows: for Bf, the entire amount of sugar was replaced with FOS. For Ryef, 50% of the white wheat flower was replaced with roughly ground wholerye (20 mesh: 12-20 mesh = 1 : 3) in addition to replacing sugar with FOS. For RS2f and RS4f, 20% of the white wheat flower was replaced with RS2 or RS4, in addition to replacing sugar with FOS. The overall preference score of Bf was similar to that of B, while those of Ryef, RS2f and RS4f were lower than that of B, but showed the acceptable degree of the overall preference. The glycemic indices of Ryef and RS2f were 46.1 and 45.9 respectively, which were significantly lower than the GI of B, 67.8. The GIs of Bf and RS4f were, however, 66.7 and 80.5 respectively, showing no significant difference compared to B. The glycemic loads for a 30 g serving were 9.5, 5.9, 6.2, 11.0 and 9.0 for B, Bf, Ryef, RS2f and RS4f, respectively. In conclusion, addition of RS2 or roughly ground whole rye to the dough formula significantly lowered the GI. Since the preferences shown for those two breads were acceptable, they may be recommended as a substitute for white bread fir persons who need blood glucose management. More studies on the bread making process are required to improve preference and acceptance. Although GI lowering effects for F and RS4 were not found in this study, further studies are needed to verify their effects.