• Korean Journal of Food Science and Technology
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• v.13 no.2
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• pp.121-126
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• 1981

An adenine-guanine doubless and $\beta$-alanine requiring mutant, D-1550-40, which had been derived from Brevibacterium ammoniagenes ATCC 6872, produced a copious amount of xanthosine-5'-monophosphate (XMP). The optimum concentration of adenine and guanine for maximal accumulation of XMP was about 75 ml/l and 100 ml/l for growth. Concentrations higher than 100 mg/l of adenine and guanine inhibited cell growth and XMP accumulation strongly. The inhibition, however, could be recovered by adding $100{\mu}g$ of biotin per liter or 0.3% of casamino acids to the culture solution. High concentrations of phosphate and magnesium salts (1.0 to 1.5%(w/v) in media) were found to be indispensable for XMP accumulation, and the presence of manganese in the culture medium stimulated both growth of cells and accumulation of XMP leaving 5'-inosinic acid unaffected. The maximal accumulation of XMP reached to 60.5 mg/l after 4 days of fermentation which had been started with a medium containing 100 mg of adenine-guanine, 5 mg of $MnSO_4{\cdot}H_2O$ and $100{\mu}g$ of biotin per liter. The specific XMP synthesis(mg of XMP/mg of cells) was increased with the increase of the cell growth rate.

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.632-640
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• 2020

In this study, we produced macarons by adding white bean powder at various proportions (0, 25, 50, 75, and 100%). The macarons in the 100% additive group had the highest moisture content, smallest volume, highest weight, and highest sugar and reducing sugar content. The macarons in the 50% additive group had the highest spread factor.Furthermore, their pH and acidity demonstrated the greatest air bubble stability. In the Hunter color system, by adding white bean powder, the L value gradually decreased, whereas the a and b values gradually increased. The hardness, gumminess, and chewiness decreased with the addition of white beans. Flavonoids and total phenolic compounds, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and superoxide dismutase (SOD)-like activity were the highest at 100%. Additionally, their overall acceptability was the highest at 50%. These results suggested that the use of white bean powder to produce macarons have numerous advantages.

• Culinary science and hospitality research
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• v.20 no.2
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• pp.79-88
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• 2014

This study investigated the quality characteristics of apple jam added with ginger. The apple jam was prepared with apples, sugar, lemon juice and various amounts (0, 2, 4, 6, 8%) of ginger. Increasing the amount of ginger decreased moisture contents and sugar content of the jam, whereas the pH gradually increased. In addition, with increased amount of ginger, the lightness(L) and yellowness(b) significantly decreased, while redness(a) gradually decreased. There wasn't any significant difference in the samples with up to 4% ginger(p<0.05). In the texture profile analysis, hardness and adhesiveness increased significantly with increased amount of ginger. When more amount of ginger was added, cohesiveness increased with no significant difference based on the amount of ginger. With increased amount of ginger, springiness and chewiness gradually increased. The results of the sensory evaluation show that the apple jam added with 4% ginger got the highest overall-acceptability scores. In conclusion, it is possible to enhance the quality and acceptability of apple jam by adding 4% ginger.

• Culinary science and hospitality research
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• v.18 no.2
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• pp.206-215
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• 2012

The results of influence on the saccharification and $Sikhea$ by adding mulberry fruit in this study are as follows. pH was decreased with the amount of mulberry fruit increased during the saccharification period. A significant change was not found after 4 hours of saccharification. It is considered that 4-5 hours was proper for saccharification because brix increased by more than 1 brix per hour up to 4 hours while there were little change after 5 hours. L was decreased while a and b values were increased in the Hunter' value of mulberry fruit $Sikhea$. The DPPH free radical scavenging activities and SOD-like activity of mulberry fruit $Sikhea$ were increased as the addition quantity of mulberry fruit increased. Anthocynin color pigment in mulberry fruit has the inhibiting effect on microbes. The preferences of mulberry fruit $Sikhea$ were 10% < 30% < 15% < 20% < 0% < 25%, and less than 25% of mulberry fruit addition seems to be desirable. The addition of mulberry fruit will help decrease the amount of sugar to use in $Sikhea$ because the sugar level of $Sikhea$ increases with the addition of mulberry fruit. It will also improve the preference for Sihkea by giving it better color and sourness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.7-11
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• 2002

Hydrothermal extraction from dates was done, and then 3 groups of the date extract liquid group (A), the date puree group (B) and the jujube skin flesh group (C) were prepared. And, the omija extract liquid was added to the 3 groups at respective rates of 3:7, 5:5 and 7:3. Then, total 9 medicated diet sources were prepared by adding cinnamon, the ginger extract liquid, honey and pectin. And their physicochenmical and sensory attributes were examined. Total sugar, free sugar and pH increased in the samples of the 3 groups as the addition amount of the jujube extract increased. In chromaticity of respective samples, the "L" value did not show any difference among the 3 groups, but the "a" value was the highest in the "A"group, and "b"value was the highest in the "B"group. In the date puree group and the jujube skin flesh group, their viscosity increased as the addition amount of the jujube extract increased, but in the jujube extract liquid group, no difference was found in its viscosity. As a result of conducting the discrimination test, it was identified that the as the addition amount of the jujube extract was increased, color and sweet taste were feltto be stronger and our taste was felt to be weaker in all 3 groups. In the jujube puree group and the jujube skin flesh group, as the addition amount of the jujube extract increased, the jujube fragrance was felt to be stronger, but in the jujube extract liquid group, no difference was found in its fragrance. And, no difference was found in brightness and viscosity between samples. As a result of conducting the palatability test, no difference was showed in the appearance, but as for the overall palatability including texture, taste and fragrance, preference increased as the addition amount of the jujube extract increased.

• Microbiology and Biotechnology Letters
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• v.3 no.1
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• pp.7-15
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• 1975

The possibilities of utilizing acid-hydrolyzate of "Sliced and dried sweet potatoes" as a carbon source for the microbial production of L-Glutamic Acid(L-GA) with Micrococcus glutamicus were investigated and the results showed as follows： 1) The highest hydrolysis rate, 74.6% of the reducing sugar based on the weight of dry matter, was obtained when the sweet potatoes were hydrolyzed with 0.8% of HCI at 2.0kg/$cm^2$ for 30 minutes. The most favorable hydrolyzate for the growth of the cells, however, was found to be the one obtained by treating the sweet potatoes with 0.5% HCI at 2. 0kg/$cm^2$ for 10 minutes. Reducing sugar content of the hydrolyzate was 10% as glucose. 2) Biotin content of the hydrolyzate was 25$\mug$/1 and it was proved to be excess in amount for the L-GA production. 3) The effects of addition of antibiotics, alcohols and fatty acid esters on the L-GA production were tested in the biotin excess medium. The production of L-GA was most increased to 32.5g/l with the addition of 10 I. U. of penicillin per ml. to the culture medium at 4 hours after inoculation. But the addition of alcohols, especially fatty acid esters, showed no significant effects. 4) Among the organic nutrients tested. " Gluten acid hydrolyzate" greatly enhanced the production of L-GA adding it＇s concentration of 1.0% to the medium. 5) The maximum production of L-GA resulted in 35g/1 when the cells were grown for 48 hours in the hydrolyzate medium supplemented with 1.0% of "Gluten acid hydrolyfate" and with 10 I. U. of penicillin per ml added at 4 hours after cultivation.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.648-654
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• 2006

This study investigated the effect of adding germinated brown rice extract powder (GBREP; 0, 0.67, 3.35, 6.70%) during the fermentation of Korean cabbage kimchi. From the result, pH was decreased and total acidity was increased. Total sugar was decreased steadily during the fermentation and reducing sugar were increased at 3 days of fermentation but then decreased steadily. Counts of total microbe and Leuconostoc sp. were increased rapidly from the beginning and reached the highest level at 12 days of fermentation, after then decreased slowly. Counts of Lactobacillus sp. were increased until 12 days of fermentation, and then maintained stably. In sensory evaluation test, the overall acceptability of Korean cabbage kimchi with 3.35% GBREP gained the highest score.

• KSBB Journal
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• v.11 no.1
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• pp.86-91
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• 1996

Optimal reaction condition for the starch hydrolysis by ${\alpha}$-amylase was determined and the sugar produced under the optimal condition was measured for estimating the biodegradation of strach-filled polyethylene film. Optimal ranges of temperature and pH were 70~$80^{\circ}C$ and 6.3~7.3, respectively. The 100 units of ${\alpha}$-amylase per mg starch were enough for the enzyme reaction. Reaction with polyethylene film containing 5%, 10%, 15% and 20% starch in the above condition showed that the sugar produced was proportional to the starch content in film. This relationship provides a calibration curve for determining the starch content of search-filled polyethylene film. The average amount of hydrolyzed starch was about 40% of total starch in film. The rest of the starch is considered to be still dispersed in the film and not to be attacked by ${\alpha}$-amylase. In this experiment, we could obtain the higher biodegradability through the $\alpha$-amylase reaction in the above optimal condition than the reported one which had been Improved by adding surfactant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.4
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• pp.51-55
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• 1986

The general bag for powder materials such as sugar, salt and detergent used at present is a simple rectangular bag. In the practical uses, it has a lot of faults: it is difficult to reseal after partial usages, occurrence of loss in the case of sharing or adding, difficult for measured uses. Author made a new type of the measuring bag for powder materials in order to improve the problems. The new type of the bag for powder materials consists of a body, fall-induced tube with length scale line, and a pin to open and reseal. It shows various effectiveness: measured use$({\pm}0.6g)$ of powder materials, eatings don't occur during long period after opening, and no skin contamination during use of detergent. Consequently, the new one Is suitable for the measured use of powder materials such as sugar, salt, detergent, MSG and so on.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.202-211
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• 2018

This study was conducted to develop a salad dressing using Prunella vulgaris L. (PV) extracts. In addition, the study was also aimed at evaluating the quality characteristics of the salad dressing containing various amounts of PV extracts. Salad dressing was prepared by adding 0% (PD-0), 9.4% (PD-20), 18.8% (PD-40), 28.2% (PD-60), 37.6% (PD-80), 47.0% (PD-100) of PV extract. The quality characteristics (sugar contents, salinity, color value, total phenol contents, total flavonoid contents, DPPH, ABTS+ radical scavenging activities, and sensory acceptability) of the dressing were analyzed. According to the results of the study, the sugar contents and salinity of salad dressing increased according to the added amount of PV extract (p<0.001). The color values of lightness and yellowness of salad dressing increased according to the added amount of PV extract, whereas color value of redness decreased (p<0.001). Antioxidant activities were improved depending on the amount of PV extracts (p<0.001). The sensory acceptability (flavor, medicinal flavor, saltiness, sourness, bitterness and viscosity) were significantly higher in the dressing added with 18.8% PV extracts than in the other samples. Based on this result, a storage experiment was conducted by comparing PD-40 and PD-C. After 4 weeks of storage at $4^{\circ}C$ and $24^{\circ}C$, the quality characteristics were observed and the pH was increased in the later stages of storage (p<0.05). The depicted that, viscosity increased with storage time at $4^{\circ}C$ (p<0.001). General bacteria and coliform were not detected during storage. These results indicated that salad dressing with the addition of 18.8% PV extracts has the best quality.