• Culinary science and hospitality research
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• v.22 no.5
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• pp.267-276
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• 2016

This study used HPLC to analyze the contents of catechins, alkaloids, and theanine of commercial green tea. Green tea samples were stored for 6 months at five different temperatures, $30^{\circ}C$, $15^{\circ}C$, $4^{\circ}C$, $-15^{\circ}C$ and $-40^{\circ}C$. Catechins change in storage temperature was $30^{\circ}C$ > $15^{\circ}C$ > $4^{\circ}C$ > $-15^{\circ}C$ > $-40^{\circ}C$ stored for 6 months. Total alkaloids content higher levels were CAF(27.49 mg/g) with lower level of TB(2.16 mg/g) and TP(0.28 mg/g). The total alkaloids content decreased in the longer storage periods, a similar case with, although CAF were almost unchanged in all storage temperatures. The results indicate that temperature and storage time are important in the storage of green tea, with refrigerated and frozen conditions as preferable to increase or preserve the chemical compounds of the green tea.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.407-411
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• 1997

Effects of heating time and storage temperature on the oxidative stability of heated palm oil were studied. Palm oil was heated at $150^{\circ}C$ for 0, 1, 10 or 20 min and stored at 4, 20 or $65^{\circ}C$. The oxidative stability of the sample was evaluated by determining peroxide value of the oil and measuring the volatiles in the headspace of the sample. Significant difference in the peroxide or volatile formation was observed (p<0.05) in heated palm oils between samples stored at 4 or $20^{\circ}C$ and those stored at $65^{\circ}C$. Pentane, hexanal, heptane and total volatiles increased with heating time, while storage temperature did not significantly affect their formation, indicating that heating time played more important role in volatile formation in the heated palm oil than storage temperature. However, adverse results were observed for the formation of peroxide. The interaction effect of heating time and storage temperature on the oxidative stability of heated palm oil was also observed.

• Food Engineering Progress
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• v.15 no.4
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• pp.311-317
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• 2011

Rice bread premix was prepared from rice flour and vital wheat gluten, and the changes in the premix properties were studied during storage at 5, 25 and $35^{\circ}C$ for 4 months. Optimum level of 14-17% vital gluten could be added to the rice bread premix. The pH, sedimentation value, and Pelshenke value of the rice bread premix decreased with increasing storage period, whereas water retention capacity (WRC) and alkaline water retention capacity (AWRC) increased with increasing storage temperature. Mixograph peak time increased with increasing storage temperature. Rapid Visco Analyser (RVA) peak viscosity and setback values increased with increasing storage temperature and period. Decreased loaf volume was observed at the rice bread prepared from the premix during storage, especially at higher temperatures. Crumb hardness of the rice bread prepared from the premix increased during 4-month storage period.

• Journal of Applied Biological Chemistry
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• v.63 no.1
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• pp.1-8
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• 2020

This study investigated the processing characteristics of soybean (HaePum) sprouts based on temperature (5, 15 and room temperature), period (0, 6 and 12 mon) and relative humidity (20, 40, 60, and 80%) during storage. The initial germination rate of soybean sprouts was 76.02±6.32%, which significantly reduced to 57.18±8.51%, and 0% as the storage temperature of soybean increased for a period of 12 mon. The germination rate of soybean sprouts with 30 ℃ and 80% RH decreased after 4 mon of storage to 4.94%. The yellowness of cotyledon of soybean sprouts was not significantly changed during the 12 mon period of storage at 5 ℃, whereas, soybean sprouts stored at 15 ℃ and room temperature demonstrated decreased yellowness. However, the stress of cotyledon decreased with an increase in both storage temperature and time, and the hardness of hypocotyl decreased with an increase of storage time. The stress of cotyledon affected by high temperature (30 ℃) and humidity (80%) during 4 mon was reduced to 44.39±9.38 g/㎟. The asparagine content of soybean sprouts showed a similar result with the germination rate due to the amount of hypocotyl. Therefore, lower temperatures and shorter storage times are suitable for soybean sprout processing. The first order kinetic model and Arrhenius equation (activation energy =29.56 kJ/mol) were able to predict the yield of sprout at various storage temperatures and periods.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.557-561
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• 2005

Effects of natural preservatives on quality and shelf-life of fresh pork were investigated by evaluating changes in physicochemical properties, sensory evaluation, and mcrobial properties during storage. Acidity and VBN values of pork with preservatives were lower than those of control. Total bacterial count of pork with preservatives was significantly lower than that of control during storage. Sensory results showed pork with preservatives had lower sensory color and off-flavor scores than control. Changes in pH, VBN, total bacterial count, coliform group, and sensory evaluation revealed pork with preservatives showed less quality changes than control during storage, regardless of storage temperature. Results indicated that addition of preservatives to pork increased shelf-life by 7 days at $4^{\circ}C$.

• Food Science and Preservation
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• v.23 no.5
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• pp.623-630
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• 2016

Inappropriate storage of fresh-cut onions may result in losses of good quality. To understand storage conditions for shelf-life and quality of fresh-cut onions, The effect of packing type and storage temperature on the quality of fresh-cut onions was evaluated. Onions stored at $0^{\circ}C$ for 2 months were peeled off after removing root and shoot parts. Each three peeled onions were packed in a polyethylene film (PE, $50{\mu}m$) or in a polyethylene/polypropylene film (PE/PP, $100{\mu}m$) with vacuum treatment (70 cmHg) and stored at different temperatures (4, and $10^{\circ}C$) for 21 days. The following analyses were examined to evaluate the quality of fresh-cut onions: microbial population, surface color, titratable acidity and pH, respiration rate, and sensory quality. Fresh-cut onions stored at $4^{\circ}C$ showed less aerobic and coliform bacterial population than those stored at $10^{\circ}C$ during observation periods. Fungal populations of fresh-cut onions packed in PE film stored at $10^{\circ}C$ increased significantly after 13 days. E. coli was not detected in all treatments during whole storage periods. Surface colors of fresh-cut onions were not affected by packing type and storage temperature, however, color difference (${\Delta}E$) of fresh-cut onions in PE/PP film stored at $10^{\circ}C$ was significantly higher than those of other treatments. Titratable acidity of fresh-cut onions was not affected by packing type and storage temperature. However, pH of fresh-cut onions packed in PE film stored at $10^{\circ}C$ increased gradually over the whole storage period. Fresh-cut onions packed in PE film showed higher $CO_2$ and less $O_2$ concentrations at $10^{\circ}C$ than those at $4^{\circ}C$. The sensory quality of fresh-cut onions was significantly affected by packing type and storage temperature after 13 days. Particularly, vacuum treatment in PE/PP film showed better sensory quality than that of PE film package at the same storage temperature. It was concluded that vacuum treatment and storage at $4^{\circ}C$ could be effective to prolong the quality of fresh-cut onions up to 21 days.

• Journal of Bio-Environment Control
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• v.9 no.1
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• pp.40-46
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• 2000

This study was conducted to investigate the comparison of storability on film sources and storage temperature and determine the proper condition for fresh Japanese mint in U storage. The fresh weight in storage was maintained well more than 40$\mu$m ceramic film(CE 40) thickness. The carbon dioxide, ethylene, and acetaldehyde contents in 80$\mu$m ceramic film(CE 80) was higher than those in CE 40. Those were not different among the storage temperatures, rather, those in 3$^{\circ}C$ and 1$^{\circ}C$ storage were higher than those in 1$0^{\circ}C$. The chlorophyll contents loss was promoted by above 5％ water loss and 0.5ppm ethylene contents, but mote than 4％ carbon dioxide contents restrained from degrading chiorophyll. The storage period in 3$^{\circ}C$ was 30 days that was twice longer than those in other storage temperatures. The visual quality was higher in CE 40 at 3$^{\circ}C$, and this plot was lowest in ion leakage that was shown the degree of chilling injury. It was concluded that storage temperature of at 3$^{\circ}C$ and packaged ceramic 40$\mu$m film to increase storability of Japanese mint would be favorable.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.8-14
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• 1996

The effects of temperature variations during storage, pasteurization on the quality of orange juices were investigated. To evaluate the quality of orange juices pasteurized at 75, 85 and $95^{\circ}C$ for 15 sec, microbial and physicochemical measurements and sensory evaluations were conducted during storage at 10, 20 and $30^{\circ}C$ for 32days. Color(lightness) and contents of vitamin C and sucrose were not changed at $10^{\circ}C$, but decreased at $20^{\circ}C$ and $30^{\circ}C$ as the storage time was increased. The pasteurization temperature had a little effect on the color and the contents of vitamin C and sucrose. Furfural contents were apparently increased as the storage period extended, but the samples stored at $10^{\circ}C$ had less amounts than the others. On the other hand, the pasteurization temperature did not affect furfural accumulation. Furfural was produced as a result of the degradation of vitamin C and deterioration of the color. The PH values were not changed during the entire storage period, and microorganisms were not detected in most of the samples. The result of sensory evaluation indicated no taste difference between the control and the sample stored at $10^{\circ}C$, but the taste changes were recognized when the samples were stored over 24 and 20 days at $20^{\circ}C$ and $30^{\circ}C$, respectively. Therefore, the storage temperature affected the quality of orange juices more markedly than the pasteurization temperature, and the storage at lower temperature appears to reduce the deterioration of orange juices.

• Journal of Internet of Things and Convergence
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• v.10 no.2
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• pp.125-130
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• 2024

With the rapid growth of mobility technology, the industrial sector is demanding storage devices that can reliably process data from various equipment and sensors in vehicles. NAND flash memory is being utilized as a storage device in mobility environments because it has the advantages of low power and fast data processing speed as well as strong external shock resistance. However, flash memory is characterized by data corruption due to long-term exposure to high temperatures. Therefore, a dedicated system for temperature management is required in mobility environments where high temperature exposure due to weather or external heat sources such as solar radiation is frequent. This paper designs a dedicated temperature management system for managing storage device temperature in a mobility environment. The designed temperature management system is a hybrid of traditional air cooling and water cooling technologies. The cooling method is designed to operate adaptively according to the temperature of the storage device, and it is designed not to operate when the temperature step is low to improve energy efficiency. Finally, experiments were conducted to analyze the temperature difference between each cooling method and different heat dissipation materials, proving that the temperature management policy is effective in maintaining performance.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.95-98
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• 1984

A pilot scale continuous Kimchi pasteurizer was used to study some factors affecting the retardation of acidification of Chinese radish Kimchi, stored at $20^{\circ}C$. The degrees of acidification of Kimchi were measured in terms of pH, acidity and absorbance. The shelf-life of the pasteurization temperature from 60 to $70^{\circ}C$ did not result in any significant effect on delaying the acidification of Kimchi during storage, while lowering of storage temperature from 25 to $5^{\circ}C$ gave rise to a marked increase in the the shelf-life of Kimchi.