• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.287-294
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• 1997

When bread making, the condition of thawing-fermentation for frozen dough were tested in variable temperature, and measured thawing-fermentation time and volume of frozen dough. L-Ascorbic acid (L-Aa) was added in frozen dough for the comparison test of develop volume in bread staling degree of baking bread were measured additive frozen dough which was stoppages in freezing, staling degrees were tested hardness with Rheometer. The test for comparison of thawing-fermentation time in variable temperature was shown the condition of dough conditioner at 3$0^{\circ}C$ was most effective for bread making, Because That condition was required very short time(74 min) But, in this comparison of volume in final products was shown the products in the condition of thawing-fermentation at 3$0^{\circ}C$ was smaller than the products at 5$^{\circ}C$(418 ml). The baking volume of L-Aa additive frozen dough which has under gone thawing-fermentation at 3$0^{\circ}C$, were shown baking volume of 420 ml in 2 weeks storage terms to 100 mg/kg L-Aa additive dough and shown baking volume of 454 ml in 4 weeks storage terms to dough of 200 mg/kg additive weight. Staling degrees of L-Aa additive frozen bread were measured with Rheometer. The hardness of 100 mg/kg L-Aa additive frozen bread was sown low level hardness in 1~2 weeks freezing term, 150 mg/kg L-Aa additive frozen bread was shown low level hardness in 3 weeks freezing term. In 4 weeks freezing term, 200 mg/kg L-Aa additive frozen bread was shown low level hardness compared with non-additive L-Aa frozen bread. In comparison of frozen bread quality, non-additive L-Aa products was better than additive L-Aa products in equality of baking shape and external apparence. But in total quality in external and internal apparence, additive L-Aa products was better than non-additive L-Aa products.

• Food Science and Preservation
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• v.4 no.1
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• pp.11-15
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• 1997

This experiment carried out to find the storage life according to the kinds of packaging material. Sheridan(Grape) which was fumigated SO2 were wrapped with polyethylenes(Bio-PE and PE) and stored at $0^{\circ}C$ under 90% RH modified condition. The resorts were summarized as follow. Natural weight loss was increased according to the storage time during the 135days storage that was only 1.0-1.7% in sealing section while 10% in non-sealing section. Abonrmal fruits were increased as the storage time was increased and it was 6.6-6.7% in sealing section while 100% in non-sealing during the 135days storage. Quality of appearance and taste are better in sealing section than non-sealing section and it was good in Bio-PE sealing section between packaging materials. Moistrue content was de creased as the storage range was increased and the decreasing rate of that during the storage was 4.9-5.2% in sealing section between treatments. During the storage range increased, the soluble solid degree was increased in non-sealing section but decreased in sealing section.

• Korean Journal of Weed Science
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• v.16 no.3
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• pp.200-209
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• 1996

It is assumed to be an efficient method for keeping a germinability of weed seeds as long as possible, if a secondary dormancy is not induced by transferring the seeds of which dormancy was broken in wetting condition into drying condition. To investigate its validity, two experiments were carried out on seeds of 9 weed species ; to find out the most effective storage condition in breaking the dormancy of each weed species and to know whether there is a decrease in the germinability by transferring into drying storage condition. The dormancy of Chenopodium album and Stellaria aquatica was released well under the drying condition, but that of Echinochloa crus-galli var. oryzicola by soaking in water. Other weed species were released from dormancy by storage in wetting condition. When the seeds stored in the wetting or soaking condition, are air-dried and then restored at room or low temperature, a decreasing tendency of germinability which might cause a trouble in using them practically, was not observed except on the seeds of Persicaria vulgaris. In the case of Persicaria vulgaris, the low germination since 3 month-storage seemed not to be caused by drying, because a decrease of its germinability was observed with increasing storage period in all of the storage conditions. In contrast, high germination was induced as the seeds of Echinochloa crusgalli var. oryzicola, which were not germinated during the storage in low temperature and wetting condition, were transferred into the room temperature and drying condition. These results suggest that this approach can be one of the efficient methods for keeping a good germinability as long as possible in most weed seeds.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1317-1323
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• 2001

The circumstance is giving the blow against fishermen with the incoming-decreasing and the difficulty of crew's supply & demand and management. In addition, the depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. First of all, we Investigated load characteristics which based on development of sea water cooling system and optimum fish hold storage. The experimental results is as follows. In creasing the speed of compressor and mass blew rate of refrigerant, the temperature of NaCl solution is low. And the load characteristics experiment on fish hold storage outlet is as fellows. As time goes by, increasing the mass flow rate of NaCl solution, temperature difference between inlet and outlet is small in a model of fish hold storage. These results provide many useful informations applicable to an actual design of sea water cooling system and optimum fish hold storage.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.168-174
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• 1998

The amount of D(-)-lactic acid in fermented dairy products is very important because the rate of metabolism of D(-)-lactic acid is lower than that of L(+)-lactic acid. The purpose of this study was to investigate the optimum condition during fermentation and storage of yogurt for the formation of isomers of lactic acid by Lactobacillus acidophilus NCFM. The production of acid was excellent at $37^{\circ}C$ of fermentation and the ratio of D(-)-lactic acid was also lower than that of other conditions such as $35^{\circ}C{\;}and{\;}40^{\circ}C$. Among shaking and non-shaking treatment under aerobic condition and anaerobic condition, non-shaking treatment under aerobic condition was the best condition at the production of acid and L(+)-lactic acid during fermentation. During storage at low temperature, a larger amount of L(+)-lactic acid was produced than at higer storage temperature.

• Journal of Biosystems Engineering
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• v.19 no.3
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• pp.232-246
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• 1994

This study was conducted to develop the long-tenn storage method to minimize the black spot occurred on the surface of persimmons stored in the films at low temperature. The storage experiments were done with different films and persimmon varieties at $0^{\circ}C$ storage condition for 5 months, and then the physical and chemical characteristics of persimmons were tested monthly. The results were as follows : 1. The film 160 made from zeolites showed highest performance in well storings sweet persimmons for 5 months, compared with other films by eyesight. The initial moisture condensation inside the films seemed to cause the black spots on persimmons, and the effect of the film holes was never significant to prevent the black spots. 2. The sugar content was ranged from $14^{\circ}Brix$ to $15^{\circ}Brix$ regardless of film types and persimmom varieties, and it changed little for storage of 5 months. 3. The decrease rate of persimmom weight in the film 160 and 180 was 0.3% for storage of 5 months, while those in other films reached to 2%. The decrease rate of persimmon weight was least in the film 160 and 180. 4. The hardness of Fuyu least decreased in the films 160 and 380. It was changed from 36 kg/cnf to 8-27 $kg/cm^2$, and that of Charyang was from 31 $kg/cm^2$ to 8-10 $kg/cm^2$ for storage of 5 months. The hardness of Charyang rapidly decreased as storage period increased. 5. The average rate of black spot(defect rate) of Fuyu measured by a computer image processing system was least in the film 160 by 0.5%, but those in other films was ranged from about 5% to 20% for storage of 5 months. The rate of black spot of Charyang was less than that of Fuyu among most of films. 6. The intensity, hue, and saturation in persimmon color changed according to storage period. Especially, the intensity of persimmon colors decreased as storage period increased, but it was least in the film 160. 7. An integrated long-term storage method of sweet persimmons was suggested in the basis of the experiments and literature reviews.

• International Journal of Advanced Culture Technology
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• v.7 no.4
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• pp.260-267
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• 2019

Harvested de-astringent persimmon 'Fuyu' were treated with various lighting sources under low (3℃) and high (22℃) temperatures. The weight loss rate of fruits was lower in those with Red LED than Fluorescence and Blue LED under both temperature conditions. Hardness and soluble solid content of fruits were higher in those with 3℃ / Blue LED or mixed LED (Blue+Red LEDs). Beta-carotene and lycopene content of fruit peel were higher in those with 3℃ than 22℃ and with Red LED or light sources with mixed red wavelength under both temperatures. When the fruits treated with light and temperature were stored for 4 days under 3℃ / dark condition, the hardness of the fruits did not significant difference among the treatments. Taken together all the results, it would be best to treat it light sources mixed red wavelength under 3℃.

• Korean Journal of Food Science and Technology
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• v.19 no.3
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• pp.206-211
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• 1987

In an attempt to improve the quality stability of dried layer (Porphyra yezoensis Ueda), during longterm storage and distribution, a 6 months storage trial at different temperature and packaging condition was conducted. Dried layer samples were prepared by conventional procedure with different washing condition and $5^{\circ}C$ and $30^{\circ}C$ were employed as storage temperature. The moisture sorption isotherm was drawn at $5^{\circ}C$ and $25^{\circ}C$ and BET equation was prepared from the moisture sorption isotherm. The monolayer moisture contents of dried layer were 7.4% at $5^{\circ}C$ and 6.4% at $25^{\circ}C$, respectively. It was also found that the changes in comprehensive quality of dried layer during storage was much less at low temperature and the degree of washing before drying process as far as its moisture contents are lower than monolayer moisture contents. With regard to the packing methods, vaccum packing was superior to air containing packaging for the maintainance of quality during storage.

• KIEAE Journal
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• v.9 no.5
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• pp.39-46
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• 2009

Most Plastic Green Houses in Korea are made according the European weather condition, which lead to have very low solar energy efficiency. Moreover, the function of green houses, as well as the structure of them, has not changed for Korean weather condition. Therefore, the structure and function of them should adopt the regional weather condition in order to improve the energy efficiency. This paper investigates the current plastic green housesin Korea, and presents an alternative for improving the energy efficiency. The elements of green houses were investigated. When using a partial opaque insulation with a thermal storage body, the difference of indoor air temperature became 20C during daytime, and 5C during night, which will save massive fossil fuels.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.331-335
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• 1985

Series of study were conducted to develop a method for longterm storage of chest-nut with preserving it's taste and freshness. Experiments were carried out with Korean chest-nut (Castanea crenata var. Okkwang) sealed in polyethylene (P.E) film stored under the ambient and low temperature. Summarized results are as follow: After the harvest, $CO_2$ produced by chest-nut at the early storage was increased with temperature increase. Q10 mg/kg/day, the temperature index of $CO_2$production, by chest-nut ranged 2.4-2.7. It was available to store chest-nut in good condition with 8-15% total loss upto the following may at the ambient temperature sealed in 0.03 mm P.E. film, and upto the following july at the low temperature if sealed in 0.03 or 0.05 mm P.E. film. Throughout the period from one month after the innitiation upto the end of the storage, the rate of $CO_2$and $O_2$ was maintained near the optimum condition for the CA storage of chest-nut. The taste of chest-nut was improved during the storage due to increased reducing-sugar and decreased wate soluble tannin. However, the taste become bitter and unacceptable from the early stage of the storage when used the thicker P.E. film (than above mentioned) for the sealing.