• Applied Biological Chemistry
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• v.41 no.3
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• pp.228-233
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• 1998

The storage life of satsuma mandarin(Citrus unshiu Marc. var. miyagawa) by the various pretreatment of temperatures; non-treated, room temperature, $10,\;20^{\circ}C$ and $35^{\circ}C$ were investigated. The pretreated citrus fruits were stored at $4^{\circ}C$, 85% relative humidity. Weight loss of citrus fruits by the pretreatment at $35^{\circ}C$ for 24 hrs was the lowest among that of others. Decay ratio of $35^{\circ}C$ pretreated fruits was increased at initial stages of storage, but was maintained low level after that, compared to other treatments. After 115 days storage, firmness of fruits was lowered by the softening, and decayed fruits were occurred increasingly. Ethylene evolution was increased between $55{\sim}65$ days after storage, and the amount was increasing rapidly after 115 days. It seemed to be derived from decayed fruits and physiological activities. $CO_2$ content in fruit was decreased at initial stages of storage, but was increased between $55{\sim}100$ days during storage periods. Acid content, soluble solids, total sugar and vitamin C were reduced gradually during cold storage, but the difference among treatments was not so great. Pretreated fruits at $35^{\circ}C$ for 24 hrs before cold storage was effective on preventing from weight loss and respiration ratio. Optimum storage period of early variety of Satuma mandarin was regarded for 100 days on the basis of appeareance and taste.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.186-193
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• 2007

Effects of deficit irrigation by different soil moisture-based water potential on the reduction of green shoulder fruits in fresh tomato were investigated. Deficit irrigation with -30 kPa treatment significantly reduced green shoulder fruit by 53.7% compared to the -15 kPa treatment. The total concentrations of potassium in levels of whole fruit was not different between normal red fruit (NRF) and green shoulder fruit (GSF). However, the concentrations of potassium in distal part of GSF lower than that of a basal part of GSF Total soluble sugar contents in NRF and GSF were increased during the maturation periods. Contents of starch in NRF and distal part of GSF were decreased during the maturation periods. However, contents of starch in basal part of GSF was not change during the maturation periods. Activity of sucrose phosphate synthase was higher in NRF than that of GSF. Activity of acid invertase in NRF and GSF decreased rapidly during the maturation periods. Activity of acid invertase was significantly different in distal and basal part of GSF. Total activities of peroxidase and alcohol dehydrogenase in NRF were higher than that of GSF.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.83-89
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• 1995

Changes in physical, chemical and microbiological characteristics of rice-doenjang prepared with two different methods with or without soak treatment were investigated during 60 days of aging at $32^{\circ}C$ and $15^{\circ}C$. The pH of soak-treated rice-doenjang decreased slowly, but that of nonsoak-treated rice-doenjang decreased rapidly at the initial aging stage with the aging temperature of $32^{\circ}C$, resulting in pH 5.1 after the 60 days of aging time. Reducing sugar contents increased up to the $30{\sim}50$ days of aging time and decreased thereafter. The contents of soluble nitrogen, formol nitrogen, ammoniacal nitrogen and amino nitrogen were more affected by preparation methods than by aging temperatures. Color values depended not only on preparation methods but also on aging temperatures. There were no significant differences in the bacterial counts of rice-doenjang, while apparent differences in the yeast and mold counts by aging temperatures were observed. These results suggested that the properties of soak-treated rice-doenjang were less changed than those of nonsoak-treated rice-doenjang by aging time and temperature. And, with a view point of nitrogen compounds, aging time could be reduced by soak treatment.

• Microbiology and Biotechnology Letters
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• v.7 no.1
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• pp.37-46
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• 1979

In order to investigate the compositional change of the lauan and pine sawdust media during the coltivation of oyster mushroom (Pleurotus ostreatus) chemical components of the two media and mushroom were analized periodically from spawning to ending. The results are summerized as follows: 1) The total yield of mushroom from the lauan sawdust media was 6.39 kg/$m^2$, and from the Pine saw-dust media 6.31 kg/$m^2$, 94％ of which was produced from the first and second cropping period. 2) In both media ash content increased gradually, while organic matter content decreased as the cultivation progressed. Moisture content, which was about 79％ at the time of spawning, decreased a little during the priod of mycelial propagation, after which no change was observed. 3) Total nitrogen content of the two media decreased gradually as the cultivation progressed, and total loss of insoluble nitrogen was greater than that of soluble nitrogen. Amino nitrogen content tended to increase continually. 4) In both media pentosan, $\alpha$-cellulose, lignin and C/N ratio decreased gradually, while the content of reduced sugar, trehalose and mannitol continued to increase. 5) In both media phosphorus, potassium, manganese and zinc decreased, and magnecium, calcium, iron and copper showed irregular changes. 6) CMC-saccharifying and liquefying activity gradually increased from after mycelial propagation to the second cropping, after which it decreased in both media. Xylanase activity rapidly and greatly increased during the second cropping period rather than the first period. At the start of the third cropping period the activity decreased slowly. Protease activity was highest after mycelial propagati, after which it gradually decreased. The pH of the two media decreased as the cultivation progressed. 7) In both media little change was observed in the content of the components of mushroom cropped from the first to the third period, but slight decrease was noticed at the fourth cropping.

• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.349-358
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• 2010

This study was carried out to investigate the optimum condition for sap exudation of Acer mono Max. tree in a site of Mt. Jiri, Hamyang-gun, Korea. Amount of sap exudation, air temperature, relative air humidity, tree diameter at breast height (DBH) and sugar content in sap were monitored during the early springtime, and correlation analysis of several factors was carried out to explain tree-to-tree and date-to-date variations in sap exudation. The correlation, linearlyassociated between DBH and sap amount, was strengthened as daily amount of sap increased, but there was no significant tree-to-tree variation in time and period for sap exudation. When amount of sap exudation was above 10 liter/day, the mean air-temperature was averaged at $1.2{\pm}1.6^{\circ}C$, the minimum at $-4.3{\pm}1.5^{\circ}C$ and the maximum at $11.8{\pm}1.9^{\circ}C$. The maximum air temperature and mean air temperature were significant (p < 0.05) factors for amount of sap in correlation analysis to explain date-to-date variation in sap exudation. Sucrose content in sap was in the range of 1.5 and 1.7% during exudation days, but sharply reduced to 0.6% level at the end of exudation period.

• Food Science and Preservation
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• v.19 no.1
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• pp.144-152
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• 2012

The temperature changes and quality characteristics of $Makgeolli$ produced using rice treated with $Gaeryang-Nuruk$ (commercial improved $Nuruk$) extract were investigated. During fermentation, the treated rice maintained a lower temperature than the control and then rose after the fifth mashing day. For all the treatments, the numbers of yeast, LAB and AAB colonies increased on the second mashing day, and then gradually decreased. As the fermentation proceeded, the pH gradually increased from the third mashing day, and eventually became higher than that on the initial mashing day. The total acid contents increased on the first mashing day, but as the fermentation progressed, they showed little change. The amino acidity and soluble solid contents during overall fermentation and reducing-sugar contents was reduced until the first mashing day, and increased from the day after. As for the alcohol content, that of the control was 6.87% on the first mashing day, and then gradually increased, nuruk-extract-treated rice began with 9~10% alcohol content and then increased as the fermentation proceeded. Among the organic acid contents, lactate was the main material. In the sensory evaluation, the 24 h-, 48 h- and 72 h- treated rice samples showed somewhat good response.

• Applied Biological Chemistry
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• v.22 no.1
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• pp.58-63
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• 1979

The solvent extracting of the tobacco has been carried out in order to find out any effects for the removal and/or reduction of nicotine from tobacco without affecting the tobacco flavor. We have now completed the physico-chemical characterization of the solvent untreated/treated tobaccos and 2) the contents of the tar and nicotine in the smoke. The results obtained ate like followings; 1. 3% alcohol extraction reduced the total nitrogen content for the Bright by 36.4%. However, it could not reduce the sugar content. 2. Nicotine content in tobacco leaves was inversely proportional to the dipping time Essentially same results were obtained in anacidic solution and even in a solution containing both alkali and acid. 3. Derivative thermogravimetric(DTG) curves indicated test extraction was effective by removing tobacco leaf components which could decompose or volatilize between the temperature of $150^{\circ}C\;and\;350^{\circ}C$. 4. 3% alcohol extracted leaf have the substantial improvements as following; (1) bulk filling power of 10% and 24% for Burley and Bright tobacco, respectively, (2) combustibility shortening of about 3 minute and 2 minute for Burley and Bright tobaccos, respectively, (3) reduction ratio(%) of nicotine was found to be shout 61.5% and 54.5% for Burley and Bright tobacco, respectively, (4) reduction ratio (%) of tar was obtained to he about 25% and 15% for Burley and Bright tobacco, respectively.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.236-243
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• 2012

The leaf growth and physiological characteristics of Forsythia saxatilis were investigated at six natural habitats under different light intensities in Bukhansan in order to figure out an appropriate growth environment for conservation and restoration of F. saxatilis that is Korean endemic plant designated as rare and endangered species. Relative light intensities (RLI) at six habitats showed from 10% to 78% of the full sun. Leaf length, leaf width, leaf area and dry leaf weight of population under highest relative light intensity (78%) were the highest. The ratio of dry leaf weight to leaf area increased with the increase of RLI. The content of photosynthetic pigments such as chlorophyll a, b and carotenoid were the highest at 78% of RLI, whereas the ratio of total chlorophyll to carotenoid content reduced according to the increase of RLI. Photosynthetic parameters, such as photosynthetic rate, also increased with the increase of RLI. The total nonstructural carbohydrate (TNC) was 1.5 times higher at 78% of RLI than that at 10% of RLI and the total soluble sugar (TSS) was the highest at 78% of RLI. In conclusion, leaf characteristics and physiological characteristics have high positive correlation with light intensity. Therefore, light condition should be primarily considered to improve growth and physiology characteristics of F. saxatilis under low light intensity.

• Journal of Bio-Environment Control
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• v.12 no.4
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• pp.221-227
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• 2003

The objective of this research was to determine the effect of seed priming on membrane integrity during poriming and germination. Among the five chemicals, $KNO_3$at 150 mL gave the shortest $T_{50}$ (days required to reach 50% of the final germination percentage). Compared to unprimed, the seeds primed with 150 mL $KNO_3$ at 20$^{\circ}C$ for 4 days had reduced $T_{50}$ values when germinated at 15$^{\circ}C$. These results indicated that seed priming is an effective way for rapid and synchronized germination, especially at low temperature. Changes in conductivity of priming solutions during the 4-days period of priming were highly dependent upon the priming agents. Conductivity of the $KNO_3$ and $K_3PO_4$ solution slowly declined during the first 3 hours ad then increased Amount of amino acids, sugars and proteins exuded from seeds into $KNO_3$ solution were less than those into distilled water and $K_3PO_4$. All the results suggested that the $KNO_3$ priming play a positive role in regulating the permeability of cell membranes.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.666-671
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• 1993

Mixtures (total solid content: 15%) prepared with whole milk added with skim milk powder and/or sweet potato and/or pumpkin were fermented with 0.205% gelatin, 2% sugar and yogurt bacteria. The fermented mixtures (curd yogurt) were evaluated for acid production (pH, titratable acidity), number of viable cell, sensory property and keeping quality. The acid production of all mixtures remarkably increased for the first 12 hours and there is no significant difference among the mixtures. The lactic acid bacteria counts in the all products after 24 hours incubation were above $6.4{\times}10^{9}cfu/ml$. In organic acids, the mixture added with skim milk powder was higher ratio of lactic acid content to total acidity than those added with sweet potato and/or pumpkin. The sensory score of mixture containing sweet potato was best but curd yogurt containing pumpkin reduced the sensory property. When each mixtures were kept at $5^{\circ}C$ for 15 days, pH, titratable acidity, and number of viable tells of yogurt were not changed.