• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.667-672
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• 2002

Concrete cooled to very low temperature cyclically is deteriorated by ice formation in micro-pores. Although the factors to the deterioration are various, storage at very low temperature is mentioned as one of the factors. In practice, storage of cryogenic structure is kept at very low temperatures, and as such, it is important to take into consideration the influence of storage at such low temperature on the deterioration of concrete. Thus, in this study, the influence of storage on the deterioration of concrete at minimum temperatures taking into consideration the different W/C and air content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1071-1076
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• 1998

Threetypes of Korean traditional kimchi were prepared using green onion, leek or godulbaegi as raw materials and stored at 5oC and 20oC for 13 days. Changes in salt and ascorbic acid contents, pH and total acidity as well as the relationship of the decomposition of chlorophylls and the production of their derivatives were investigated. For the all kimchi samples tested, salt content was not significantly changed during storage at both temperatures, whereas pH and total acidity were decreased and increased, respectively. Especially their remarkable changes were shown at the third day of storage. Ascorbic acid content was remained at high level in the leek kimchi for the experimental period at both storage temperatures, meanwhile godulbaegi kimchi retained the least amount of ascorbic acid. Chlorophylls were decomposed to pheophytin and pheophorbide during storage at both storage temperatures, and this phenomenon was apparent at the third day of storage. Reduction of chlorophylls and increasements of its decomposed products such as pheophytin and pheophorbide were the least in leek kimchi and the greatest in godulbaegi kimchi during storage at both temperatures. These results indicate that decomposition of chlorophylls in kimchi and increasements of pheophytin and pheophorbide were closely related to the ascorbic acid content in kimchi.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.5
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• pp.427-435
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• 2005

This paper investigates the thermal storage performance of the office building which has adopted an air conditioning system with its slab structure as a regenerator. Four cases of the thermal storage performance experiment were conducted. Room air temperatures, floor slab temperatures, temperatures around the air conditioning unit were logged and analyzed. The load handling capacity of the air conditioning unit and the amount of heat stored in the slab were decided from those experiments. Several efficiencies were investigated to evaluate the performance of the thermal storage. The results concluded that the slab as a regenerator is very effective in cutting down peak loads of the office building.

• Journal of dental hygiene science
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• v.10 no.6
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• pp.459-464
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• 2010

The purpose of this study was to evaluate the physical properties of hydrophilic polyvinyl siloxane impression materials as change of material's storage temperatures. Working time, strain-in-compression, elastic recovery and consistency were tested according to ISO Standard NO. 1563. The results are as followed. 1. Working time decreased in cold storage. 2. Strain-in-compression was different in storage temperatures. Material's strain-in compression in cold temperatures were higher than in room temperature and in incubator. 3. A coefficient of elastic recovery varied by storage temperatures. The rate in cold temperature was the lowest and in incubator was the highest. 4. Consistency of impression substance different in storage temperatures. The extent in cold temperature is the highest and in incubator was the lowest. Statistical analysis(SPSS 14.0k, p>0.05) showed that storage temperature affect to material's physical properties. We recognized that the physical properties of polyvinyl siloxane impression materials were changed according to storage temperature.

• Korean Journal of Organic Agriculture
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• v.30 no.2
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• pp.291-302
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• 2022

Food safety is a fundamental requirement for consumers. Therefore, this study was aimed to determine the freshness of pork fillets based on freshness index (Ki value) analysis during storage. This study obtained a total of 24 pork fillets. This study was divided into 4℃ and -20℃ temperatures. Again, each temperature was divided into 4 different groups based on storage durations (15d). Each group was obtained in triplicate. The level of malondialdehyde (MDA) value was significantly increased at 4℃ than the -20℃ storage with the duration of storage days. The levels of inosine-5'-phosphate (IMP) in pork fillets were significantly decreased at 4℃ and -20℃. Hypoxanthine (Hx) levels were significantly increased at 15 days than those at 0 days during storage at both temperatures (4℃ and -20℃). Subsequent freezing increased more inosine levels at -20℃ than storage at 4℃. The Ki values were increased during storage days at both temperatures, although after 15d storage, its values at 4℃ were significantly higher than those at -20℃. These results demonstrated that storage period and temperature might affect the freshness of pork fillets via lipid oxidation and nucleotide degradation. This study suggested that the Ki value will be the crucial indicator of measurement of freshness of stored pork fillets.

• Mycobiology
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• v.51 no.6
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• pp.445-451
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• 2023

Shiitake mushroom (Lentinula edodes) hold high nutritional and medicinal value as they contain an abundance of health-promoting compounds. However, the effect of long-term postharvest storage on the variation in the levels of health-promoting compounds has not been extensively studied. In this study, we investigated the changes in the levels of phenolic compounds, antioxidants, eritadenine, and ergothioneine in shiitake mushrooms stored at three different temperatures (1, 3, and 5 ℃) for 4 weeks. Compared to mushrooms stored at lower temperatures, those stored at 5 ℃ exhibited a higher level of total phenolics in their pileus after 2 weeks of storage; however, storage at 5 ℃ also increased the deterioration of the fruiting body of these mushrooms. In mushrooms stored at all temperatures, the eritadenine content in the pilei tended to increase up to 2 weeks of storage. In contrast, the ergothioneine content in the pileus decreased during storage, with a significantly lower level detected in mushrooms stored at 5 ℃ for 4 weeks. Together, these results suggest that the mechanisms underlying the accumulation of phenolics and eritadenine may be related to mushroom deterioration during storage. Our findings indicate that the levels of health-promoting compounds in shiitake mushrooms are influenced by storage temperature, suggesting the potential to control adjustments of specific bioactive compounds by regulating storage conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.832-840
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• 2014

This study aimed to investigate the effects of storage duration and temperature on the characteristics of wet brewers grains (WBG) as feeds for ruminant animals. Four storage temperatures ($5^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$) and four durations (0, 1, 2, and 3 d) were arranged in a $4{\times}4$ factorial design. Surface spoilage, chemical composition and microorganism density were analyzed. An in vitro gas test was also conducted to determine the pH, ammonia-nitrogen and volatile fatty acid (VFA) concentrations after 24 h incubation. Surface spoilage was apparent at higher temperatures such as $25^{\circ}C$ and $35^{\circ}C$. Nutrients contents decreased concomitantly with prolonged storage times (p<0.01) and increasing temperatures (p<0.01). The amount of yeast and mold increased (p<0.05) with increasing storage times and temperatures. As storage temperature increased, gas production, in vitro disappearance of organic matter, pH, ammonia nitrogen and total VFA from the WBG in the rumen decreased (p<0.01). Our results indicate that lower storage temperature promotes longer beneficial use period. However, when storage temperature exceeds $35^{\circ}C$, WBG should be used within a day to prevent impairment of rumen fermentation in the subtropics such as Southeast China, where the temperature is typically above $35^{\circ}C$ during summer.

• Food Science of Animal Resources
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• v.40 no.3
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• pp.415-425
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• 2020

It is believed that two main proteolytic systems are involved in the tenderization of meat: the cathepsins and the calpains. Many researchers consider the calpain system to be the major contributor to meat tenderness during post-mortem storage. However, the role and activity of cathepsins during post-mortem storage or low temperature meat processing is unclear, particularly for the tough meat cuts like brisket. Thus, the study was designed to investigate the effects of cold (refrigerated and frozen) storage and sous vide processing on the activities of cathepsin B, H, and L in beef brisket. There were no significant changes in pH and cathepsin H activity throughout the 18 d of storage at both temperatures. However, an increase in cathepsin B activity was observed during the first 4 d at both storage temperatures, but subsequently the activity remained unchanged. Cathepsins B and L were found to be more heat stable at sous vide temperatures (50℃ for 24 h, 55℃ for 5 h and at 60℃ and 70℃ for 1 h) compared to cathepsin H. Cathepsin B+L activity was found to increase after sous vide cooking at 50℃ for 1 h but decreased to about 47% relative to the uncooked control after 24 h of cooking. These results suggest that cathepsins B and L may contribute to the improved meat tenderness usually seen in sous vide cooked brisket meat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.852-857
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• 1998

Three kinds of kimchi using Chinese cabbage, leafy radish and mustard leaf were prepared by conventional method and stored at 5$^{\circ}C$ or 2$0^{\circ}C$ for 13 dyas. During storage at both temperatures, changes of the amounts of salt and ascorbic acid, pH and total acidity were determined, and the relationship of the decomposition of chlorophylls with the production of their derivaties was studied. At both storage temperatures, salt concentration of Chinese cabbage kimchi(3.7%), leafy radish kimchi(3.6%), mustard leaf kimchi(3.5%) was relatively constant during the entire storage period. However, pH and total acidity wre fluctuating with the remarkable changes during 3 days of storage. Ascorbic acid content was slowly decreased during the storage period and the decompositin rate of ascorbic and was greater at 2$0^{\circ}C$ than 5$^{\circ}C$. Among the kinds of kimchi tested, mustard leaf kimchi with the slow decomposition rate of ascorbic acid contained relatively high ascorbic acid content, while leafy radish kimchi contained the lowest content. At both storage temperatures, the production of pheophytin and pheophorbide from decomposition of chlorophyll was least in mustard leaf kimchi, but similar production rates in leafy radish and Chinese cabbage kimchi were observed.

• Journal of Forest and Environmental Science
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• v.37 no.3
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• pp.235-242
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• 2021

Seed morphology, physiology and environmental conditions have influence on germination of any tropical seeds and their appropriate handling, processing and handling enhances seeds emergent. This study therefore investigated effects of storage durations under different temperatures on germination of Bombax costatum seeds from different provenances. Fresh 25 seeds of B. costatum in four replicates were collected from four different provenances (Aponmu, Oluwa, Ibadan and Oyo). They were surface sterilized, thoroughly washed in distilled water and stored at four different temperature regimes: 28℃, 21℃, 5℃ and -17℃. Samples were taken every 2 months for germination test for 18 months. Germination assessment was carried out daily and recorded. The experimental design was 4×4×10 factorial in 4 replicates. Data were subjected to percentages and analysis of variance (ANOVA). Results showed that there were significant differences among storage temperatures, storage durations and provenances on germination percentage. Freshly collected seeds from Aponmu and Oyo had the highest mean germination of 100% followed by seeds from Ibadan (89.3%). Seeds from Oyo provenance stored 5℃ had germination of 94.0%, 88.70% and 78.7% at 2nd, 4th and 6th month respectively. Seeds from Ibadan and Oyo stored at 28℃, 21℃ recorded 0.0% starting from 8 months of storage. Germination of B. costatum seeds from the four provenances decreased with increase in storage duration at different temperatures.