• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.55-61
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• 1987

This study was carried out to investigate the changes in the pH, extractability of protein, ATPase activity of myofibrillar protein, myofibrillar fragmentation, freezing loss and drip loss during storage at $4^{\circ}C$ and $-20^{\circ}C$ in breast and leg muscle of spent-hen meat. pH values ill pectoral and leg muscle were lowest ell tile 1st day and 1st week during cold and frozen storage, respectively. The extractabilities of myofibrillar proteins were increased graduall during cold storage and were highest on the 1st week during frozen storage, The $Mg^{2+}-ATPase$ activities of myofibrillar proteins were highest on the 1st day and 1st week during cold and frozen storage, respectively. The myofibrillar fragmentations were greatly changed on the 1st day during cold storage and 1st week during frozen storage. Freezing losses and drip losses were increased gradually during frozen storage. pH values in breast muscle were lower than those of leg muscle, and the extractabilities, $Mg^{2+}-ATPase$ activities, fragmentations of myofibrillar proteins, and drip losses in breast muscle were higher than those of leg muscle during storage, but the patterns of the changes in both muscles were similar during storage.

• 한국가스학회:학술대회논문집
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• no.5
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• pp.111-118
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• 2002

• Food Engineering Progress
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• v.22 no.4
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• pp.321-327
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• 2018

The main purposes of this study were to identify the factors affecting the supercooling property and to improve the possibility of supercooling storage of fruits and vegetables. Freezing point and nucleation temperature, moisture content, hardness, sugar content, and pH of nineteen fruits and vegetables were measured and Pearson correlation analysis was performed. Freezing point showed a statistically significant correlation with moisture content and sugar content (p<0.01), while ice nucleation temperature showed a correlation (p<0.05) only for sugar content. In particular, the water content and sugar content did not show any correlation with the freezing supercooling difference (FSD). From the correlation analysis between FSD, aerobic bacteria, lactic acid bacteria, yeast, and mold, FSD showed a correlation (p<0.01) with aerobic bacteria. The experiments of the saline solutions inoculated with aerobic bacteria at different concentrations showed FSDs of about 2 for saline inoculated with 9.4 log CFU/mL and about 6 for saline inoculated lower than 5 log CFU/mL. Therefore, the aerobic bacteria concentration was determined to be a key factor affecting the supercooling storage of fruits and vegetables.

• Solar Energy
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• v.19 no.2
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• pp.1-8
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• 1999

The heat transfer characteristics of ice storage system of falling film type using sprial coil is investigated. The experimental facilities consisted of a water tank, spiral coils located above the tank, an upper water distributor, and a circulating water pump. Water is distributed uniformally over the spiral coils and it forms falling thin films. In the process of freezing, ice is formed on outside of the spiral coils through recirculation of tank water. In the process of melting, ice is melted with return water from the heat load, while the water is chilled again and drops into the tank. The results of falling film type of ice thermal storage system are as follows. The highly efficient shower flowrates for icing is near $3{\ell}/min$. Icing rates on spiral coils is rosed while brine flowrates is increased. Lower brine temperature is not only increased freezing rates but. also become higher total icing weight and overall heat transfer coefficient. Smaller shower flowrates is obtained lower water temperature on outlet for a long time. The amounts of quantity can be detected more accurately by measuring storage tank weight.

• Food Science and Preservation
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• v.14 no.5
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• pp.462-468
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• 2007

In this study, the quality effect of soaking in alum water, soaking in electrolyzed oxidizing water, and freezing during storage, on peeled chestnuts, were analyzed. When soaked in 0.1% (w/v) alum water, peeled chestnuts showed good characteristics in terms of weight loss, decomposition, and color preservation. However, texture and taste qualities rapidly decreased with increases in storage time. When soaked in twice their own weight of electrolyzed oxidizing water(pH 2.61, ORP 1,142 mV) for 10 min, the samples were preserved in an optimally edible condition. When frozen at $-10^{\circ}C$ for 5 min, the samples were suitable for use as material for processed chestnut produce, as was also the case when pretreatment with electrolyzed oxidizing water was employed.

• Tunnel and Underground Space
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• v.15 no.3 s.56
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• pp.169-176
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• 2005

The decreasing pattern of underground temperature measured at 'Gonjiam cold storage cavern' during 7 years which was the first commercial scale underground food storage cavern in Korea was analyzed. The variation of energy consumption was discussed by comparing the consumed energy at the initial operation stage with that at later stage, when the temperature distribution reached a stabilized condition. The point to be considered at the design stage was also discussed by comparing the required refrigerator capacity at the initial operation stage with that at later stage. The extra energy to freeze the groundwater contained in pore space was discussed by analyzing the changing pattern of the rock temperature. The variation of measured rock temperature was compared with the estimated temperature using a numerical code, FLAC. The accuracy of the numerical estimation was discussed by comparing the heat flux measured by the operation time of the refrigerator with that estimated numerically.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.267-276
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• 2007

This study was conducted to determine the effect of cryoprotectants (sugar, sorbitol, polyphosphate) on the physico-chemical characteristics of chicken breast surimi manufactured by pH adjustment (pH 11.0) during freezing storage. The final surimi was divided into experimental units to which the following treatments were randomly assigned: C (Alaska pollack surimi: two washings, 4% sugar +5% sorbitol ${\pounds}'$ 0.3% polyphosphate additive): T1 (chicken breast surimi: pH 11.0 adjusted, 0.3% polyphosphate additive): T2 (chicken breast surimi pH 11.0 adjusted, 5% sorbitol +0.3% polyphosphate additive); T3 (chicken breast surimi: pH 11.0 adjusted, 4% sugar +5% sorbitol +0.3% polyphosphate additive). The crude protein content of the control was higher than all treated samples, however the moisture, crude fat and crude ash of T3 were higher than the control (p<0.05). The pH, WHC and collagen content of the control were higher than all of the treated samples, and these values decreased with storage time for all treatments and the control (p<0.05). The cholesterol content of the control was lower than all treated samples, but the myofibrillar protein contents of all treated samples were higher than the control (p<0.05). The cooking loss of T2 was lower than the control and the other two treatments (p<0.05). The $L^*,\;a^*\;and\;b^*$ values of all treated samples were higher than those of the control during freezing storage (p<0.05). The W value of T3 at 1.5 and 3 months of freezing storage was higher than the control and T1 (p<0.05). The myoglobin and met-Mb contents of the control were similar to all treated samples, and the met-Mb content of the control and all treated samples increased with storage time (p<0.05). Immediately after freezing, the hardness of the control was higher than all treated samples, however it was lower after 1.5 and 3 months of frozen storage (p<0.05). The cohesiveness and gumminess of the control were higher than all treated samples immediately after freezing, however the values for T3 were higher than those of the control and the other two treatments during frozen storage for 1.5 and 3 months (p<0.05).

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.361-366
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• 2001

The purpose of installation of the brine heating system for LNG storage tank is the prevention of ground freezing. If the ground of LNG tank areas is frozen, it is caused by safety problems. The design of brine heating system for LNG storage tank which is constructing in our country is not well considered about domestic weather conditions and economical efficiency. Therefore, this paper reports on the study of the optimized temperature of inside pipes and cooling process through the transient analysis by using the existing brine heating system.

• Solar Energy
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• v.20 no.4
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• pp.61-67
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• 2000

The purpose of this study is to improve heat transfer by attaching rectangular fins to tube. Experiments were carried out under the following conditions - Aspect ratio$(W_f/R_f)$ is 0.7, 1.2 and 1.8. Temperature conversion between high and low positions of water in the thermal storage appeared because maximum density point of water is about $4^{\circ}C$ and inlet direction of working fluid influenced conductive heat transfer Compared with the unfinned tube(bare tube), the rectangular tube increased the ice thermal storage energy and the ice thermal storage energy was increased as aspect ratio was increased.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.901-905
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• 2000

An experiment was conducted to investigate the effect of caffeine, cAMP and cattle seminal plasma on preservation of semen at ultra low temperature ($-196{^{\circ}C}$). Each semen sample was divided into four parts equal in volume and sperm concentration; three were treated with caffeine, or cAMP, or cattle seminal plasma (CSP) and the fourth was kept as control. Sperm motility, abnormal spermatozoa, live-dead count and acrosomal damage were studied at different stages of freeze preservation viz.; just after dilution, at $5{^{\circ}C}$, at glycerolisation, before freezing, just after freezing, 24 hours of storage, and one week of storage. Sperm motility (58.39, 61.33, 52.00 and 50.39 per cent), non-eosinophilic spermatozoa (72.55, 69.98, 63.31 and 67.64 per cent), abnormal spermatozoa (5.71, 4.98, 8.04 and 5.66 per cent) and acrosomal damage (13.28, 13.33, 14.80 and 14.65 per cent) were observed in cAMP, caffeine, cattle seminal plasma and control, respectively, at every stage of freeze preservation. From this study it could be concluded that freezability of buffalo semen can be improved through the addition of caffeine followed by cAMP and cattle seminal plasma.