• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.21-25
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• 1987

In order to obtain a basic understanding of the storage of Satsuma mandarin sacs, the canned sacs were stored at room temperature from Feb. 20 to June 20(4 months), after dipping in chlorine solution and pasteurization as a pretreatment before canning. In general, the brix, acidity and pH of the sacs were almost not affected by the chlorine treatment ana a variety of pasteurization temperatures during storage. The broken rate was apperently increased by chlorine treatment, especially in the early stage of storage. However, the broken sacs were partially recovered in the end of storage. The contents of total carotenoid were almost not decreased by the conditions of the pretreatments during storage. The contents of vitamin C were sharply decreased between 3rd and 4th month of storage time on all sample. As a result, the decrement of vitamin C in canned sacs was caused by storage temperature rather than the condition of the pretreament.

• Elastomers and Composites
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• v.42 no.3
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• pp.159-167
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• 2007

Hydraulic actuators are used widely for industrial machinery. The seal made from elastomer is used as a core part of the actuator, NBR(nitrile butadiene rubber) materials with high quality of oil resistance and abrasion resistance is used widely, requiring excellent characteristic of sealing. According to applied circumstances, the actuators for industrial machinery are used under different temperature situations. In this study, three different kinds of NBR, which is Hs70, 80, 90 are determined as one of hydraulic materials. An experimental investigation is performed to confirm the non-linearity under different temperature ($-10^{\circ}C,\;20^{\circ}C,\;80^{\circ}C,\;100^{\circ}C$) situation, material constants for finite element analysis and plastic deformation in accordance with Load-unload.

• Food Science and Preservation
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• v.6 no.4
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• pp.376-379
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• 1999

In an attempt to test the storage life of late maturing-medium grapes, Sheridan, Tano Red and Muscat Bailey A cultivated widely in Korea, were selected as test samples. These grapes were treated with SO2 gas and packed with polyethylene film, then stored at 0$^{\circ}C$ under 90% RH. Total weight decreased with the storage days and the loss extent of Sheridan was the least. Abnormal grapes increased along with the storage days and occurred rapidly after 90% days. After 135 days, these were produced as the following order. Sheridan < Muscat Bailey A < Tano Red. The external appearances were deteriorated with the storage days. After 135 days, these indices of Sheridan, Muscat Bailey A and Tano Red wen 6.3, 5.0 and 1.7, respectively, showing the most satisfactory result from Sheridn. Water content decreased along with the storage days. The soluble solids content and the proportionality of sugar to acids increased with the storage days, however the titratable acidity decreased. Considering these results, the storage lifes were excellent by the order Sheridan, Muscat Bailey A and Tano Red.

• Journal of the Korean Society of Radiology
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• v.15 no.7
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• pp.1057-1064
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• 2021

This study was conducted by simulating the same environmental conditions as the actual biopsy to observe the change in formaldehyde(HCHO) concentration in the indoor air during ultrasound guided biopsy. Changes in HCHO concentration in the room were measured by successively performing five steps: sealing the ultrasound room, ventilation, opening formalin containers, sealing formalin containers, and re-ventilating. Trends of measured HCHO concentration changes were visualized using graphs. As a result of analyzing the consistency of the concentration change values measured three times using the intra-class correlation coefficient, it was found to be 0.989, which was statistically significant(p<0.05). Based on the results of this study, we hope that medical workers working in the HCHO exposure environment of the field of radiology part will improve their awareness of the necessity of exposure management at work, and actively discuss the establishment of an environment for exposure control and preparation of countermeasures.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.864-871
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• 2014

Seed viability is affected by storage conditions and rapid loss of viability in storage is the major cause for low germination. This study was carried out to examine the effect of packaging materials and storage temperature on seed germination rate over 10 years in two species (Capsicum annuum L. and Brassica rapa L. ssp. pekinensis) and determine effective storage conditions for maintaining seed viability. Seeds were packaged in aluminum poly pouches under vacuum, polyethylene bottles, and paper bags containing silica gel and stored under one of two controlled conditions ($15^{\circ}C$, RH 40% or $5^{\circ}C$, RH 30%) or at ambient condition. Seed germination was recorded at 6-month intervals for 10 years. The seeds of both species showed no decline in viability until 6.5 years at 15 or $5^{\circ}C$, irrespective of packaging materials. However, under ambient conditions, the seeds of chili pepper and Chinese cabbage in paper bags lost viability after 4 and 5 years, respectively. By contrast, seeds of both species in vacuum-aluminum poly pouches exhibited a 99% germination rate after 6 years under ambient conditions. Pepper seeds in the vacuum-aluminum poly pouches maintained a 93% germination rate after 10 years in ambient conditions. These results indicated that a special seed storage facility for maintaining viability of chili pepper and Chinese cabbage seed might not be essential and seed testing would not be necessary for 10 years, if chili pepper and Chinese cabbage seeds were packed in ambient/vacuum-aluminum poly pouches or $5^{\circ}C$/vacuum-aluminum poly pouches.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.123-129
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• 1986

These studies were conducted to elucidate the effect of storage conditions on the changes of chemical components in fruit bodies of oyster mushroom(Pleurotus ostreatus), and the results obtained were as follows. 1. The fruit bodies of oyster mushroom sealed with polyethlene film 0.03 mm thickness maintained their freshness for 15 days at $1^{\circ}C$, 10 days at $5^{\circ}C$ and 3 days at $20^{\circ}C$. 2. The respiration rates of the fruit bodies grown in the rice-straw substrate was 29.7mg $CO_2/kg$ F.W/hr. at $1^{\circ}C$, 32.7mg at $5^{\circ}C$, and 46.3mg at $20^{\circ}C$ during the storage, respectively. The respiration rate showed the highest level at the second day during the storage. 3. The contents of total and reducing sugar during the storage of oyster mushroom rapidly increased at $5^{\circ}C$ until the fifth day following slowly decreased. 4. The content of protein in the oyster mushroom was reduced during the storage, while the free amino acid slightly increased. 5. The change of RNA and DNA contents during the storage of oyster mushroom showed inconsistency on the temperature and the storage period.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.201-206
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• 1985

This experiment was carried out to get the basic information about long term storage (Temp.: -10${\pm}$1$^{\circ}C$ and -l${\pm}$1$^{\circ}C$, RH; 30${\pm}$6) of rice germplasm by using three Japonica and one Indica x Japonica cultivars based on the storage periods (96, 86, 58 and 20 months). The germination ability, based on the storing periods, was tested under the conditions of 30-32$^{\circ}C$ and 15-17$^{\circ}C$ air temperature. The results obtained are summarized as follows: 1. There were no significant differences between the short and long term storage conditions in the percentage of germination, average germination period, germination coefficient of the four varieties tested under both 15-17$^{\circ}C$ of low and 30-32$^{\circ}C$ of optimum temperature conditions. 2. Eventhough there were no significant differences in germination depending on the storage periods under optimum temperature condition (30-32$^{\circ}C$). Longer storage duration resulted in lower germination percentage, longer average germination period and lower germination coefficient under low temperature condition (15-17$^{\circ}C$). Comparing the varieties, the germination percentage of a Indica/Japonica cultivar "Tongil" was lower than that of Japonica cultivars under the low temperature condition (15-17$^{\circ}C$). 3. The longer period of storage, the more abnormal plants had appeared. 4. The germination ability was lost earlier under the condition of high moisture content in the seed and non-ventilation container.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.31-36
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• 2000

180g of fermented soy paste and 150g of red pepper paste were packaged in glass jars of 232 mL with different conditions of active packaging and then stored at $13^{\circ}C$ for about 170 and 128 days, respectively. During the storage, package atmosphere, surface color, pH, acidity and microbial flora were monitored to see the effect of packaging conditions. Test packaging conditions include package equipped with $Ca(OH)_2\;as\;CO_2$ absorber, package with pinhole and closed control one. Closed control packages of soypaste and red pepper paste showed the increased $CO_2$ partial pressure, the decreased $O_2$ partial pressure and the constant $N_2$ partial pressure to produce high pressure buildup with storage. The paste packages with $Ca(OH)_2$ maintained relatively low $CO_2$ partial pressure and thus the package pressure close to normal atmospheric pressure for initial storage period of 70 days. The packages with air pinhole channel had the partial pressures of $O_2\;and\;N_2$ decreased with storage time, while $CO_2$ partial pressure first increased to a maximum and then slowly decreased thereafter Without any pressure increase the packages with pinhole gave the lowest quality changes possibly due to the effect of package atmosphere, but it had problem of mold contamination and growth for soy paste after 120 days. There were no difference in microbial flora between the packages after about 70 day storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.130-138
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• 1981

Discoloration of canned boiled oysters during storage is one of the serious problems which affect the quality of the products as well as the nutritive value. Usually the factors influencing the quality of canned boiled oysters are the process of pretreatments and the storage temperature of the products. In the present work, the changes of the total chlorophylls and carotenoids in the meat and the viscera of oysters were determined in order to make certain the procedure of the discoloration. In addition, the amino-N and the available lysine as factors of the nutritive value were also checked. In case of treatment with additives, direct addition of syrups containing additives just before seaming or soaking boiled oysters into the solution of additives seemed to have mild effects on retardation of discoloration. The migration of carotenoids from the viscera into the meat was faster than that of chlorophyll resulting in yellowing of the Products preceded greening caused by the chlorophylls. Treatment with $0.5\%\; Na_{2}EDTA\;of\;2.5\%$ brine retarded discoloration and available lysine loss of the Products while sodium-polyphosphate accelerated them. It was probably due to that sodium-polyphosphate could affect the softening or breakdown of the muscle of oysters. But most of all, storage temperature of canned boiled oysters seemed to be the major factor influencing the discoloration and nutritive loss of the products.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.703-709
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• 1993

The changes in molecular size distribution of rice starch during extrusion cooking and simple heating of rice flour were compared and the effect of subsequent enzyme treatment on the molecular size was examined. A single-screw extruder was used with varing feed moisture contents ($17{\sim}29%$) and barrel temperatures ($100{\sim}150^{\circ}C$). An aluminium capsule immersed in oil bath ($100{\sim}200^{\circ}C$) was used for the simple heat treatment of rice flour. In case of extrusion cooking the mechanical energy input varied sharply at around 23% moisture content of the feed. At the feed moisture content of $17{\sim}23%$, a significant molecular size reduction of rice starch was observed by the gel permeation chromatography using Sephacryl S-1000 gel. The intact starch molecules of above $4{\times}10^{7}$ dalton were largely disintergrated by extrusion cooking of rice flour containing the moisture content less than 23%. It was mostly degraded further into the molecules having below $5{\times}10^{6}$ dalton by ${\alpha}-amylase$ treatment. But at the feed moisture content above 26% the starch did not show molecular size reduction either by extrusion cooking or by subsequent enzyme treatment. On the contrary little changes in molecular size of starch was occured by simple heating of rice flour containing the moisture less than 20%. but slight size reduction was observed at the moisture content above 23%, where the effect of ${\alpha}-amylase$ was also observed.