• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.618-622
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• 1997

This study was carried out to investigate the effect of storage temperature (0, 5, $20^{\circ}C$) on chemical components of Korean kiwifruits. Moisture content decreased in $0^{\circ}C-,\;5^{\circ}C-stored$ samples and slightly increased in $20^{\circ}C-stored$ sample. Soluble solid content increased in $0^{\circ}C-,\;5^{\circ}C-stored$ samples and decreased in $20^{\circ}C-stored$ sample ranging from 11 to $14\;^{\circ}Brix$. pH and titratable acidity remained at the level of $3{\sim}3.5$ and $1{\sim}1.5$, respectively. The content of malic and quinic acid increased during storage at $0^{\circ}C$ and $5^{\circ}C$. In case of citric acid, the content increased up to 6th week and then decreased. Kiwifruits stored at $20^{\circ}C$ showed a changing pattern of organic acids similar to those stored at 0 and $5^{\circ}C$. Glucose, fructose and sucrose increased in $0^{\circ}C-,\;5^{\circ}C-stored$ samples except fructose at $5^{\circ}C$. In case of $20^{\circ}C-stored$ sample, sucrose increased up to 2∼3th week and then decreased.

• Korean journal of applied entomology
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• v.40 no.4
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• pp.297-300
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• 2001

Development and reproduction of the persimmon fruit moth, Stathmopoda masinissa, were investigated under different temperatures (15, 20, 25, and 3$0^{\circ}C$). It took 96.1 days to grow from egg to adult at 2$0^{\circ}C$, 43.2 days at $25^{\circ}C$, and 34.6 days at 3$0^{\circ}C$. At 15$^{\circ}C$, all tested individuals died before pupation. The developmental threshold temperatures for egg, larva, pupa, and adult were 12.2, 13.5, 13.8, and 13.4$^{\circ}C$, respectively. The total effective temperatures for egg, larva, pupa, and egg to adult were 74.0, 331.3, 160.5, and 569.9 degree days, respectively. The hatching, pupation, and emergence rates were highest at $25^{\circ}C$. The average life span of adult prior to laying eggs and the total life span of adult were 12.6 and 29.3 days at 2$0^{\circ}C$, 3.8 and 8.6 days at $25^{\circ}C$, and 2.5 and 7.0 days at 3$0^{\circ}C$, respectively. Mean generation time in days (T) was shorter at higher temperature. Net reproductive rate per generation (R$_{o}$) was lowest at 2$0^{\circ}C$. The intrinsic rate of natural increase (r$_{m}$) was highest at $25^{\circ}C$ as 0.066.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.123-128
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• 2002

This study was carried out to test the effects of temperatures between 2$0^{\circ}C$ and 3$0^{\circ}C$ on the reproduction and development of the rice water weevil, Lissorhoptrus oryzophilus. Preoviposition periods were much longer (17.2 to 51.0 days) in the overwintering adult females collected in March than those collected in May, regardless of temperature. Oviposition periods, however, were longer (16.9 to 22.0 days) in the adult females collected in May than those collected in March at the same temperatures. The longer oviposition period observed in the females collected in May were directly associated with higher fecundity. Egg periods were shortened from as temperature increased, but the hatching rate was highest (100%) at 27$^{\circ}C$. The developmental periods from egg to adult were shortened as temperature increased : from 77.9 days at 2$0^{\circ}C$ to 38.3 days at 3$0^{\circ}C$. The developmental zero point temperature (T) and the total effect temperature (K) for egg were 16.3$^{\circ}C$ and 62.1 dgree days, respectively. The T and K from egg to adult emergence were 13.9$^{\circ}C$ and 577.6 dgree days, respectively. The adult females of the first generation did not oviposit at 2$0^{\circ}C$, but did at $25^{\circ}C$ and 3$0^{\circ}C$. The intrinsic rate of natural increase (r$_{m}$) increased as temperature augmented. Net reproductive rate (Ro) per generation was highest (75.3) at $25^{\circ}C$.>.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.253-262
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• 1995

To develop a device for measuring fish freshness which could be move accurate and reliable than used freshness measuring systems. A new device based on digital circuit was designed using a microcomputer. The device was composed of a sensor part, 8096 microprocessor and a segment display. The effectiveness of device has been evaluated by the coefficient of correlation among the measured freshness stores such as electrical Q-value, K-value and amount of volatile basic nitrogen (VBN) of plaice, Paralichthys Olivaceus, during storage at $-3^{\circ}C,\;0^{\circ}C,\;5^{\circ}C,\;10^{\circ}C,\;and\;25^{\circ}C$. Q-values measured by a new device were more closely correlated with K-value (r=-0.978-\;-0.962,\;p<0.05) and VBN (r=-0.888-\;-0.988,\;p<0.05) in case of plaice meat. If more data would achieve using various fishes, this new designed device could be a valuable kit in fish market by its compact portability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.482-488
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• 1998

This study was carried out to determine the effect of treating with salt-fermented shrimp on quality of pig meat. The treated pig meats were stored at 4$^{\circ}C$, 1$0^{\circ}C$, 2$0^{\circ}C$ or 4$^{\circ}C$ after placing 2$0^{\circ}C$ for 35 hours, respectively. Meat tenderness was improved more at 2$0^{\circ}C$ storage than at 1$0^{\circ}C$ and 4$^{\circ}C$ storage. However, in water holding capacity, the meat stored at 4$^{\circ}C$ was increased more than them of 1$0^{\circ}C$ and 2$0^{\circ}C$. Cooking loss was decreased more at 4$^{\circ}C$ than the other storage temperatures. When meat color observed, it was good at the early stage of storage but went down to the worse gradually. According to the result of SDS-PAGE, myofibrillar proteins were degraded more after treated with salt-fermented shrimp than the control. Among them, titin-I was especially degraded after 2 days at 4$^{\circ}C$ storage even though it was degraded after 1 day at 1$0^{\circ}C$ and 2$0^{\circ}C$ storage. These results suggest that salt-fermented shrimps cause to improve the quality of pork meats by increasing the meat color, meat tenderness and water holding capacity at the early stage of storage.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.110-116
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• 1997

Growth curves of seven strains of lactic acid bacteria isolated from Kimchi were graphed during cultivation at 1$0^{\circ}C$, 2$0^{\circ}C$, 3$0^{\circ}C$ and 4$0^{\circ}C$ in filter sterilized Chinese cabbage juice, and then lag time and generation time at each conditions were calcurated. At 3$0^{\circ}C$, the lag time of Leu. mesenteroides subsp. dextranicum was 168 min(minutes), Leu. mesenteroides subsp. mesenteroides 204 min, Leu. paramesenteroides 612 min, Lac. bavaricus 258 min, Lac. homohiochii 228 min, Lac. plantarum 270 min and Lac. brevis 264 min. And at this temperature, the generation times of Leu. mesenteroides subsp. dextranicum and Leu. mesenteroides subsp. mesenteroides were all 36 min, Lac. bavaricus 33 min, Lac. homohiochii 39 min, Lac. plantarum 66 min, Lac. brevis 42 min and Leu. paramesenteroides 162 min. As cultural temperature was lowed from 3$0^{\circ}C$ to 1$0^{\circ}C$, all strains showed remarkable prolongations in lag time and in generation time, and the prolongations were most conspicuous in Lac. plantarum. At 1$0^{\circ}C$, 2$0^{\circ}C$ and 3$0^{\circ}C$, both the lag time and the generation time of Leu. mesenteroides subsp. mesenteroides were shorter than those of Lac. plantarum. But at 4$0^{\circ}C$, this pattern was completely inverted. As a whole lower temperatures were more favorable for the growth of Leu. mesenteroides subsp. mesenteroides, while higher temperatures were for Lac. plantarum.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.537-543
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• 2003

As pyrite is commonly associated with arsenopyrite, the use of pyrite including arsenopyrite for medicine requires close attention on arsenic toxicity. The toxicity was reduced by traditional processing operations include heating and quenching in vinegar. To verify the scientific effects of this process, pyrite containing many crystals of arsenopyrite was processed at temperatures from 45$0^{\circ}C$ to 85$0^{\circ}C$ and through as many as 5 processing cycles. Arsenopyrite completely disappeared when processed only once at $650^{\circ}C$ while it remained even after 5 processing cycles at 45$0^{\circ}C$. Arsenic was most abundant in medicinal mineral samples processed at 45$0^{\circ}C$ and sharply decreased when processed at $650^{\circ}C$ or 85$0^{\circ}C$ And arsenic extraction test in water was carried out from the processed pyrite medicine on the assumption that pyrite medicines with the lowest As metal content would be most desirable. Arsenic were most abundant in water extracted from medicinal mineral samples processed at 45$0^{\circ}C$ and sharply decreased when processed at $650^{\circ}C$ or 85$0^{\circ}C$. But the extracted As concentrations in water exceeded drinking water standards even when processed at 85$0^{\circ}C$. Increasing temperature promoted elimination of arsenopyrite and reduction of As in medicinal minerals and the extraction solutions. But the effects of processing cycles at the same processing temperature were not clear. Heating temperature is more important than number of processing cycles for the removal of arsenic, and it is necessary to heat pyrite to over $650^{\circ}C$ to remove it.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.217-223
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• 2003

Effects of temperature on the development and reproduction of the Luciola lateralis were investigated at various temperatures. The development time of eggs, larvae, and pupae were shorter at higher temperatures than at lower ones. The insect did not develop at 10$^{\circ}C$ and 35$^{\circ}C$. The hatchability was 61.5% at 15$^{\circ}C$, 73.9% at 20$^{\circ}C$, 93.3% at 23$^{\circ}C$, 91.8% at 25$^{\circ}C$, 74.0% at 27$^{\circ}C$, and 46.0% at 30$^{\circ}C$, indicating the best hatchability rate at the temperature condition of 23 DC. Larval periods were 341.5:t 23.2 days at 15$^{\circ}C$, 265.5${\pm}$17.5 days at 20$^{\circ}C$, and 250.9${\pm}$11.7 days at 25$^{\circ}C$. Pupal periods were 94.7${\pm}$11.5 days at 15$^{\circ}C$, 41.7${\pm}$9.1 days at 20$^{\circ}C$, and 18.5${\pm}$7A days at 25$^{\circ}C$. Emergence rate was 23.3, 89.3 and 80.7%, respectively at the above temperatures. Adult longevity of female was 18.0 days at 15$^{\circ}C$, 2004 days at 20$^{\circ}C$, 10.7 days at 25$^{\circ}C$, and 5.8 days at 30$^{\circ}C$. Mean fecundity per female was higher at 20$^{\circ}C$ compared with at other temperatures. The developmental zero point temperatures (1) and the total effect temperatures (I<) of egg, larva, pupa, and complete development were 10.6, 14.0, and l3.1$^{\circ}C$ and 214.8, 1,564.8, and 229.2 degree-days, respectively. Mean generation time in days (T) was shorter at higher temperature. Net reproductive rate per generation (Ra) was the lowest at the highest temperature as well as at the lowest, and it was 177.19 which was the highest at 23$^{\circ}C$. The intrinsic rate of natural increase (r$\sub$m/) was highest at 27$^{\circ}C$ as 0.019. As a result, optimum range of temperature for L. lateralis growth was between 20-25$^{\circ}C$.

• Applied Biological Chemistry
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• v.49 no.2
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• pp.108-113
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• 2006

This study was conducted to analyze the acidity and turbidity changes of immersion solutions as well as changes in aerobic bacteria, E. coli, anaerobic bacteria, yeast and mold counts of mulberry leaf soybean curds during storages at $4^{\circ}C$ and $25^{\circ}C$ in different immersion solutions such as distilled water, grapefruit seed extract (300 ppm) and alkaline ionic water. The acidities of immersion solutions of distilled water, grapefruit seed extract and alkaline ionic water after 18 days of storage at $4^{\circ}C$ were 0.021, 0.008 and 0.002%, respectively. After 5 days of storage at $25^{\circ}C$ were 0.042, 0.029 and 0.009%, respectively. The turbidities of the above mentioned immersion solutions were 0.50, 0.29 and 0.21 after 18 days of storage at $4^{\circ}C$ and 0.38, 0.34 and 0.27, respectively, after 5 days of storage at $25^{\circ}C$. The acidity and turbidity changes of immersion solutions were sensitive to storage temperatures. The aerobic bacteria count of mulberry leaf soybean curds after 18 days of storage at $4^{\circ}C$ was still below $10^7\;CFU/g$, the beginning point of soybean curd putrefaction; in contrast, this value was reached within one day in distilled water at $25^{\circ}C$ and between 2 and 3 days in alkaline ionic water. Grapefruit seed extract and alkaline ionic water had a better preservative effect at $4^{\circ}C$ than at $25^{\circ}C$ storage temperature.

• The Korean Journal of Food And Nutrition
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• v.11 no.3
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• pp.329-333
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• 1998

The effects of 0.5%(v/v) acetic acid (AA), 0.5%(v/v) lactic acid(LA), or 0.5%(v/w) citric acid(CA) on gram-negative bacterial counts (GNC) and aerobic plate counts (APC) in flatfish strips stored at 4$^{\circ}C$ or 1$0^{\circ}C$ were assessed. Treatments of 0.5% AA were completely (P<0.05) inhibited GNC compared to the initial controls for 12 days at 4$^{\circ}C$. Treatments of either LA or CA rapidly increased GNC compared to those of AA after 9 days at 4$^{\circ}C$. Treatments of AA were microbiological acceptable for 6 days at 1$0^{\circ}C$, but those of LA and CA did not lasted. AA treatments were completely (P<0.05) inhibited aerobic spoilage bacteria (APC) compared to the initial controls for 6 days at 4$^{\circ}C$. Treatments containing either 0.5% LA or 0.5% CA were ineffective after 9 days at 4$^{\circ}C$ and 3 days at 1$0^{\circ}C$, respectively. Based on these results, AA treatment was the most effective for suppressing the growth of aerobic spoilage bacteria during storage at both 4 and 1$0^{\circ}C$. Flatfish strips treated with 0.5% AA extended microbiological shelf-life for 12 days at 4$^{\circ}C$.