• The Korean Journal of Mycology
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• v.40 no.4
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• pp.210-214
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• 2012

The aim of this study was to determine changes of physicochemical properties and microorganisms of commercial Makgeolli during storage at $10^{\circ}C$ and $25^{\circ}C$ During storage at $10^{\circ}C$ for 11 days, ethanol contents did not increased up to 7.0%, and pH and total acidity were ranged with 3.12-3.99 and 0.22-0.28%, respectively. Makgeolli which was storaged at $25^{\circ}C$ for 11 days showed more than 7.0% of alcohol contents, pH of 3.96-4.17 and total acidity of 0.27-0.30%. Yeast cell counts showed maximal $2.90-16.00{\times}10^7$ CFU/mL at $10^{\circ}C$ for 3 days and $1.12-29.40{\times}10^7$ CFU/mL at $25^{\circ}C$ for 1 day. Lactic acid bacteria and total bacteria cell counts of Makgeolli which was storaged at $25^{\circ}C$ for 11 days were higher than those $10^{\circ}C$ storage. In preference test, Makgeolli from storage at $10^{\circ}C$ for 11 days was showed the level of 4.9-5.2 points however, Makgeolli from storage at $25^{\circ}C$ for one day showed below 5.0 point.

• Food Science and Preservation
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• v.11 no.1
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• pp.22-27
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• 2004

In order to endow mackerel fillet with antioxidant effect, functionality and remove fishy smell, chitosan, oligosaccaride, extracts of green tea, dill weed and ginger was used as soaking solution additives. Quality characteristics of soaked mackerel fillet(SMF) was investigated during storage temperature and time after vacuum packing with polyvinyl chloride film. From the results of VBN measurement, initial spoilage was showed within 2 or 3 weeks in SMF soaked with brine including extracts of green tea, herb and ginger at 5$^{\circ}C$. In case of adding chitosan and oligosaccarides to the solution mentioned above, initial spoilage was found from 4 to 7 weeks, oxidation was reduced remarkably and SMF stored at -20$^{\circ}C$ maintained the freshness during 80 days. Viable cell counts were reached to 108 for 3 weeks storage at 5 and 0$^{\circ}C$. But no change of viable cell counts was founded at -20$^{\circ}C$. The shelf-lifes of SMF according to 5, 0 and -20$^{\circ}C$storage temperatures were 2 to 3, 4 to 7 weeks and about 3 months, respectively.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.390-393
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• 1997

${\kappa}-Carrageenan-based$ film prepared by mixing 2% ${\kappa}-carrageenan$, 0.1% KCl, 0.75% polyethylene glycol, and 0.75% glycerol was examined to be used as a potential packaging material for mackerel mince for preventing moisture loss and lipid oxidation. Mackerel mince patties were vacuum-packaged with the film and stored at $20^{\circ}C,\;10^{\circ}C,\;0^{\circ}C,\;and\;-15^{\circ}C$; nonpackaged patties were also stored at $0^{\circ}C$. Weight reduction, peroxide value (PV), and thiobarbituric acid (TBA) value were measured during storage. The packaged or nonpackaged samples stored at $20^{\circ}C,\;10^{\circ}C,\;and\;0^{\circ}C$ showed a 60% weight reduction between 2 and 15 days of storage, while the weight reduction of the samples stored at $-15^{\circ}C$ was about 3% after 25 days. The nonpackaged samples stored at $0^{\circ}C$ showed a steady increase in lipid oxidation with the PV reaching 23 mequivalent peroxide (PO)/㎏ on day 20 and with the TBA value at 0.4 mole malonaldehyde (MA)/g on day 5. The PV and TBA values of the samples vacuum-packaged with the carrageenan-based film were below 2 mequivalent PO/㎏ and below 0.1 mole MA/g, respectively, regardless of storage temperature throughout the storage of 28 days.

• Proceedings of KOSOMES biannual meeting
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• 2007.11a
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• pp.187-188
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• 2007

The fluctuations of biochemical and molecular activities III the harmful dinoflagellate, Cochlodinium polykrikoides, depending on water temperatures, were studied. In genomic DNA concentration, a similar value of 0.6 was shown at $12^{\circ}C$ and $15^{\circ}C$, but significantly increasing DNA from $18^{\circ}C$ (p<0.05), with a maximum of 1.8 at $24^{\circ}C$. After$24^{\circ}C$, the DNA significantly decreased to 0.6. Likely, the concentrations of RNA and total protein were at their highest values of 1.7 and 0.07 g $mL^1$ at $24^{\circ}C$, respectively. In contrast to ONA, RNA and total protein began to increase at $15^{\circ}C$. Oxygen availability between lower and higher temperatures was significantly different and increased from $18^{\circ}C$ according to light intensity, regardless of wavelengths (p<0.05). At $24^{\circ}C$, the highest value of the maximum electron transport rate (ETRmax), ranging from 537.9 (Ch 1) to 602.5 mol electrons $g^{-1}$ Ch1 a $s^{-1}$ (Ch 4), was also shown. Nitrate reductase (NR) and ATPase activities were at their highest values of 0.11 mol $NO_2^-g^{-1}$ Ch1 a $h^{-1}$ and 0.78 pmol 100 $mg^{-1}$ $at^2$ $4^{\circ}C$, respectively. When the cells cultured at $15^{\circ}C$, NR and ATPase activities significantly increased compared to $12^{\circ}C$ (p<0.05). In an analysis of CHN, the concentration of C and N also significantly increased (p<0.05). However, at $27^{\circ}C$, most of the molecular and biochemical movements were much lower, compared to $24^{\circ}C$. These results suggest that C. polykrikoides is very sensitive biochemical and molecular activities depending on water temperatures. Possibly, it is desirable to estimate at $18^{\circ}C$ the initiation of the massive blooming development of C. polykrikoides. In nature, it will be very difficult to maintain the massive blooms after $24^{\circ}C$ because of the possibility of significantly decreasing the molecular movement and activity of C. polykrikoides.

• 한국해양학회지
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• v.18 no.1
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• pp.55-63
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• 1983

The study on the periodic and correlation analysis between water temperature and air temperature has beenconducted by oceanographic data obtained from 1923 to 1979 (For 16-51 years) in 6 ststions in the Korean Waters. The periodic and correlation analyses has been examined by method of he Schuster's and the quadratic formula of least squares method, respectively. The results pbtained from the study are as follows; 1. Periodic analysis 1) The yearly difference between max. and mini. fo surface water temperature was 12.77-17.99$^{\circ}C$ (computed value : 11.67-16.64$^{\circ}C$) in offshore waters, and was 15.72-26.33$^{\circ}C$ (computed value : 15.13-25.29$^{\circ}C$) in inshore waters, and that of air temperature was 21.71-28.60$^{\circ}C$ (computed value : 10.50-27.22$^{\circ}C$). 2) The yearly mean of water temperature by station was 11.25-18.78$^{\circ}C$, and that of air temperature was 11.39-16.16$^{\circ}C$. 3) The annual compnent amplitrde of water temperature was 5.72-12.54$^{\circ}C$, and that of air temperature was 10.04-13.49$^{\circ}C$. 4) The semi-annual component amplitude of water temperature was 0.83-1.30$^{\circ}C$, and that of air temperature was 0.72-1.26$^{\circ}C$. 5) The annual component phase of water temperature was 215-228$^{\circ}C$ (max. temperature shall be in the first and in the middle ten days of August) in inshore waters and 138-244$^{\circ}C$ (max. temperature shall be in the first and in the middle ten days of August) in offshore waters, and that of air temperarture was 212-221$^{\circ}C$ (max. temperature shall be in the first and in the middle ten days of July and in the first tin days of August). 6) The semi-annual component phase of water temperature was 87-110$^{\circ}C$ in offshore waters, and 167-212$^{\circ}C$ in inshore waters, and that of air temperature was 156-189$^{\circ}C$. 2. Correlation analyses of water temperature and air temperature before one month. 1) When the water temperature is in rising time, the quadratic constant of correlation formual was the gradual inreasing type ( constant; 0.010-0.026) in offshore waters, and the gradual decreasing or proportional type (constant; -0.020-0.001) in inshore waters. 2) when the water temperature is in descending time, the quadratic constant of correlation formula was the gradual increasing type (constant: 0.012-0.021) 3) the determination coefficient was 0.964-0.992 at rising time and 0.982-0.999 at descending time of water temperature.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.181-198
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• 1998

In order to determine the optimum pasteurization conditions by microwave heating(MWH) at $50^{\circ}C{\sim}70^{\circ}C$ for 30 minute compared with water bath heating(WBH) at $65^{\circ}C$ for 30minute during storage at $5^{\circ}C$, the chemical composition, microbiological changes and keeping quality were examined and the results were as follows: 1. The fat protein lactose, total solid contents of raw milk, at $50{\sim}70^{\circ}C$ for 30 min. in MWH and at 65 for $30^{\circ}C$ min. in WBH did not changed significantly during the storage at $5^{\circ}C$. 2. The pH and acidity for the raw milk untreated were 6.75 and 0.16%, and those of MWH heated and WBH milk wee 6.75~6.50 and 0.16%~0.19%, phosphatase test were negative at $61^{\circ}C$ for 20 min. at $62^{\circ}C$ for 15 min. at $63^{\circ}C$ for 10 min. at $64^{\circ}C$ for 5 min. at $65^{\circ}C$ for 5 min. in MWH and at $65^{\circ}C$ for 30 min. in WBH. 3. Whey protein content was $18.53mg/m{\ell}$ in raw milk untreated, however, those were decreased as the heating temperature increased. The proteolytic activity of treated milk by WBH(44%) was lower than that by MWH(94%). 4. Total bacteria counts were $2.8{\times}10^5CFU/m{\ell}$ in raw milk untreated, $2.8{\times}10^3CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. $2.4{\times}10^3CFU/m{\ell}$ at $70^{\circ}C$ for 30 min. in MWH and $3.0{\times}10^3CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. in WBH. Because total bacteria count did not increased in MWH at $65^{\circ}C$, $70^{\circ}C$ for 30 min. and $65^{\circ}C$ for 30 min. in WBH during the 10 days storaging, Also, total bacteria counts for treated milk were a most drastic decrease after $61^{\circ}C$, $62^{\circ}C$, $63^{\circ}C$, $64^{\circ}C$, $65^{\circ}C$ for 5 min. in MWH. 5. Coliform bacteria counts were $2.6{\times}10^3CFU/m{\ell}$ in raw milk untreated. There were not detected at $55^{\circ}C{\sim}70^{\circ}C$ for 30 min. in MWH and at $65^{\circ}C$ for 30 min. in WBH. Coliform bacteria counts were not detected after $61^{\circ}C$, $62^{\circ}C$, $63^{\circ}C$, $64^{\circ}C$, $65^{\circ}C$ for 5 min. in MWH. 6. Thermoduric bacteria counts were $5.2{\times}10^4CFU/m{\ell}$ in raw milk untreated, $2.0{\times}10^3CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. $1.9{\times}10^3CFU/m{\ell}$ at $70^{\circ}C$ for 30min. in MWH and $2.2{\times}10^3CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. in WBH. Because thermoduric bacteria counts did not increased in MWH at $65^{\circ}C$, $70^{\circ}C$ for 30 min. and $65^{\circ}C$ for 30 min. in WBH during the 10days storaging. Also, thermoduric bacteria counts were a most drastic decrease after $61^{\circ}C$, $62^{\circ}C$, $63^{\circ}C$, $64^{\circ}C$, $65^{\circ}C$ for 5 min. in MWH. 7. Psychrotrophic bacteria counts were $2.8{\times}10^5CFU/m{\ell}$ in raw milk untreated, $2.0{\times}10^1CFU/m{\ell}$ at $65^{\circ}C$ for 30 min. $2.0{\times}10^1CFU/m{\ell}$ at $70^{\circ}C$ for 30 min. in MWH and $3.0{\times}10^1CFU/m{\ell}$ at $65^{\circ}C$for 30 min. in WBH. Because psychrotrophic bacteria counts did not increased in MWH at $65^{\circ}C$, $70^{\circ}C$ for 30min. and $65^{\circ}C$ for 30 min. in WBH during the 10 days storaging. Also, psychrotrophic bacteria counts were a most drastic decrease after $61^{\circ}C$, $62^{\circ}C$, $63^{\circ}C$, $64^{\circ}C$, $65^{\circ}C$ for 5 min. in MWH.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.223-228
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• 1985

Photosynthetic inhibition to temperature were conducted with ginseng(4 year old) and tobacco(var. Bulgaria). The plants were kept under various temperature conditions from 1$0^{\circ}C$ to 4$0^{\circ}C$ and 440$\mu$E/$m^2$/sec for 3 and 6hrs, and net $CO_2$ uptake were measured after 2hrs at $25^{\circ}C$. Photosynthetic optimal leaf temperature of ginseng was 21$^{\circ}C$ and tobacco was $25^{\circ}C$. Stomatal resistance and mesophyll resistance increased at high temperature. Especially, stomatal resistance seemed to have a significant role in determining the temperature responses of photosynthesis. In tobacco photosynthetic capacity was not changed by temperature treatment for 3hrs. However, 6hrs exposure reduced 8% of net photosynthesis at 4$0^{\circ}C$ and 12% at 1$0^{\circ}C$. Ginseng plants exposed for 6hrs at 4$0^{\circ}C$ lost photosynthetic capacity by 83%. Temperature responses of ginseng were very sensitive at above-optimum temperature resulting greater thermal inhibition other than photoinhibition.

• Journal of Life Science
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• v.11 no.3
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• pp.203-210
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• 2001

To produce the instant marsh calm(Corbicula elatior) soup with abundant taste and flavor. optimum conditions of heating temperature and time for extraction were investigated. Excretion rate in a pre-treatment for excretion of estuary was 82% at 15% salt concentration for 6 hr and 95% at pH 7.5 for 10 hr. The contents of glycogen and amino-nitrogen were the most high levels in the treatments extracted at 9$0^{\circ}C$ for 3 hr, at 10$0^{\circ}C$ for 1.5 hr and at 11$0^{\circ}C$for 1 hr. The contents of total free amino acids in the extracts treated at 9$0^{\circ}C$, 10$0^{\circ}C$ and 11$0^{\circ}C$ were 367.05mg/100g, 472.23 mg/100g and 463.54 mg/100g, respectively and optimal temperature was above 10$0^{\circ}C$. The mineral contents was the most high level for the extract treated at 10$0^{\circ}C$ for 1.5hr. The results of sensory evaluation showed that tastes for the marsh calm extracts had no significant discrimination, while external appearances and flavors for the extract done at 10$0^{\circ}C$ for 1.5 hr were excellent. The extracts at 10$0^{\circ}C$ showed a little dark color and those at 9$0^{\circ}C$ smell a little fish flavor.

• Journal of the Korean Ceramic Society
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• v.20 no.2
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• pp.153-160
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• 1983

This study was carried out to research the change of mineral phases and the characteristics(apparent specific gra-vity water absorption firing shrinkage modulus of rupture thermal expansion and specific dielectric constant) of the sintered bodies manufactured by kaolin and limestone. Samples were composed of the same theoretical composition as it of anorthite and fired up to 145$0^{\circ}C$ Investigated the change and micro-structure of the mineral phases by XRD and SEM the characterisdtics of the sintered bodies by TMA Automatic Capacitance Bridge and etc. The results were as follow. 1. Reactions of sintering are occurred between 860-95$0^{\circ}C$ and 1200-138$0^{\circ}C$ and state of bloating is occurred at 1410-145$0^{\circ}C$ 2. For the inclusion of feldspar and its fine particles of materials the temperature of producing and collapsing is decreased. 3. Pseudo-wollastonite and gehlenite are formed about 95$0^{\circ}C$ 4. At 114$0^{\circ}C$ anorthite are begin to forming and increase continuously to 138$0^{\circ}C$. Above 141$0^{\circ}C$ content of anorthite are decreased. 5. The variations of bending strength with sintering temperature reflect similar trend of sintered contraction and in-crease continuously from 120$0^{\circ}C$. At 145$0^{\circ}C$ reached about 680kg/cm2. 6. Specific dielectric constant$($\varepsilon$_s)$ of specimen sintered at 141$0^{\circ}C$ is 7.12 and that value is most favorable.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.135-140
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• 2000

Development and reproduction of the cotton caterpillar, Palpita indica, were investigatedunder different temperatures (15 .O, 17.5, 20.0, 22.5, 25 .O, 27.5, 30.0, 32.5, and 35 .O$^{\circ}$C). Duration fromegg to pre-adult of the cotton caterpillar were ranged from 68.6 days at 175$^{\circ}$C to 19.7 days at 35.0% (3.5times shorter growth period compared with that at 17S$^{\circ}$C). At 15.0$^{\circ}$C, cotton caterpillar eggs developedto the last larval instar but were not able to go through the pupal stage. The lower developmentalthreshold temperatures and degree-days of egg, larva, pupa, and complete development were 13.4, 10.6,11.6, and 11.5"C and 55.3,251.5, 138.3, and 479.8 degree days, respectively. The hatching, pupation andemergence rates were higher at 25.0eC and 27.5"C compared with other temperatures. The survival ratefrom the hatched larva to adult was the highest at 27.5"C. The preoviposition and the adult longevity were11.5 and 30.6 days at 17.5"C and 1.5 and 9.2 days at 35.0$^{\circ}$C, respectively. The mean fecundity perfemales was greater at 25.0$^{\circ}$C and 27.5"C compared with other temperatures. Mean generation time indays (T) was shorter on higher temperature. Net reproductive rate per generation (R,) was the lowest atthe highest temperature as well as at the lowest, and it was 199.1 which was the highest at 27.5"C. Theintrinsic rate of natural increase (r,) was highest at 30.0$^{\circ}$C as 0.148. As a result, optimum ranges oftemperature for P. indica growth were between 25.0-32.5"C .emperature for P. indica growth were between 25.0-32.5"C .t;C .