• Food Science of Animal Resources
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• v.38 no.5
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• pp.959-969
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• 2018

This study investigated the effects of deep freezing and storage temperature ($-50^{\circ}C$, $-60^{\circ}C$, and $-80^{\circ}C$) on the quality and freshness of lamb. To compare the qualities of deep frozen and stored lamb, fresh control and normal freezing conditions ($-18^{\circ}C$) were adopted. As quality and freshness parameters, drip loss (thawing loss and cooking loss), water-holding capacity (WHC), texture profile analysis (TPA), thiobarbituric acid reactive substances (TBARS), and total volatile basic nitrogen (TVBN) were evaluated during 5 months of storage. Temperature influenced the drip loss and WHC, and deep freezing minimized the moisture loss during frozen storage compared to the normal freezing condition. Lamb frozen and stored at deep freezing temperature showed better tenderness than that stored in normal freezing conditions. In particular, lamb frozen at lower than $-60^{\circ}C$ exhibited fresh lamb-like tenderness. Regardless of temperature, evidence of lipid oxidation was not found in any frozen lamb after 5 months, while TVBN was dependent on the applied temperature. Therefore, this study demonstrated that deep freezing could potentially be used to maintain freshness of lamb for 5 months. From the quality and economic aspects, the freezing and storage condition of $-60^{\circ}C$ is estimated as the optimum condition for frozen lamb.

• Korean Journal of Poultry Science
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• v.14 no.2
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• pp.145-151
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• 1987

In order to select the optimum freezing condition for the minimization of physico -chemical changes such as protein denaturation, lipid oxidation and pH change, the effect of freezing rates on the poultry meat quality changes was studied during frozen storage at -20$^{\circ}C$. Results obtained from the experiments are as fellows. When chicken breast and leg meat were frozen at above -3cm/hr or the freezing rate, pH change during frozen storage was minimal Although TBA value and free ratty acids were increased during frozen storage, the effect of freezing rates was different depending on muscle types. In terms of protein extractability, the extractability of salt soluble protein and water soluble protein were the highest at above -3cm/hr of the freezing rate during frozen storage. This trend was more obvious with breast meat than leg meat. Considering the above - described results, above -3cm/hr of the freezing rate seemed to be the optimum freezing condition for chicken meat because or the least pH change, low TBA value and high protein extractability.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.405-411
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• 1994

This study was conducted to know the quality of chou made with flour pastes which were stored at different conditions of quick freezing, slow freezing, cold and room temperature. Also, this study included investigation of the chou properties such as expansion, sensory evaluation, degree of gelatinization, and physical and structural properties of paste were observed. There were not significant differences m diameter, height, volume, appearance, hollow formation, and sensory evaluation between the chou made with the paste stored at freezing condition and chou directly baked after pasting. Quick and slow freezing storages did not significantly affect the properties of chou, and the same results were obtained among the chou made with pastes thawed at room temperature and in microwave ovenrange. The chou of pastes stored at room temperature and in microwave ovenrange. The chou of pastes stored at room temperature and stored in refrigerator showed lowed expansion and value of sensory evaluation than those of frozen pastes. The paste stored at room temperature had the lowest hardness and viscosity compared with the other storage conditions. According to the observation of light microscope. the lipid bodies of the paste of freezing storage smaller those of the room temperature and refrigerator storage. The expantion of chou made with paste stored at room temperature was greatly decreased due to the high coalescence of lipid bodies, and also the paste components such as lipid, starch granule gluten at room temperature had inferior dispersion condition. The general tendency of the degree of gelatinization of chou were low in all treatments of paste. The values were 23.5%~46.0% in freezing, 77.3% in room temperature, 68.7% in directly baked after pasting, and 61.0% in cold storage, respectively. The formation and the taste of chou made with frozen paste were similar to those of chou directly baked pasting.

• 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.

• Journal of Food Hygiene and Safety
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• v.26 no.1
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• pp.31-35
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• 2011

Arcobaeter butzleri is one of the aerotolerant Campylobaeter species which cause persistent diarrhea, abdominal pain, nausea and vomiting in human. The aim of this study was to determine the growth and survival of A. butzleri under the heat treatment or freezing storage condition. In heat treatment, two Korean isolates of A. butzleri were treated at 40 to $80^{\circ}C$ for various times. In freeze treatment, two Korean isolates of A. butzleri were kept at 4, -20 and $-70^{\circ}C$ from 1 to 15 d. The survivability of the A. butzleri Korean isolates significantly decreased at higher than $60^{\circ}C$ heating condition but it didn't show any significant difference in $40^{\circ}C$ treated group. Under the cold stress condition, survivability of A. butzleri were significantly decreased at $-20^{\circ}C$ storage. Like other foodborne pathogens, survivability of A. butzleri was controlled by heat and freezing treatment.

• Korean Journal of Medicinal Crop Science
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• v.13 no.1
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• pp.52-56
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• 2005

This study was compared the quality of red ginseng and characteristic changes of physicochemical properties according to the storage period (non storage, two days, six days, eight days, ten days) and store temperature $20^{\circ}C, \;34^{\circ}C,\;-10^{\circ}C)$. The water content of the fresh ginseng has a tendency to decrease as storage time increases. When we store the fresh ginseng for 10 days, the ideal storage temperature is considered to be $34^{\circ}C$ degrees. The amount of total nitrogen has a tendency to increase more than that of no storage as storage period approaches to 10 days. In the storage temperature, the amount of total nitrogen has a tendency to increase in the order of 1) room temperature, 2) freezing storage, 3) cold storage more than no storage. Cold storage has larger contents of total phenolic compounds than room temperature and freezing storage according to storage temperature. When we analyze the changes of a relative density of eight elements, ginsenoside $Rb_1,Rb_2,Rc,Rd,Re,Rg_3,Rg_1\;and\;Rg_2$ in red ginseng's saponin Rf according to storage condition, the relative density of $Rb_1\;and\;Rg_1$ against Rf diminishes in each storage condition as storage time increases. And it is also thought that density change of ginsenoside appears because of the materials, and change tendency according to storage condition is not clear. From functional nature on the evaluation of the quality, taste and fragrance of red ginseng according to storage district, it is evaluated that it is most recommendable for red ginseng to be transported and stored in $3{\sim}4$ degrees to keep its best condition.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.793-797
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• 1999

Salmonella typhi Ty21a is an attenuated strain of S. typhimurium and used for oral typhoid vaccine. In an attempt to increase the stability of Ty21a manufacturing typhoid vaccine, we studied about the stability of freeze-dried Th21a including additives at various temperature conditions. In order to investigate the freeze-drying rate of Ty21a according to various absorbance, we lyophilized Ty21a by using 8% sucrose as a stabilizer. The optimal freeze-drying rate of Ty21a was appeared when OD (optical density) value of the growth was between 2.5 and 3.0. To investigate the stability of Ty21a at various temperature, the viability was measured after storaging the freeze-dried Ty21a at the room temperature, cold and freezing condition for 1 week. The viability of Ty21a in cold and freezing storage condition was 5 times more stable than in room temperature. To search the most stable additives for the freeze-dried Ty21a, the viability of Ty21a including additives at the various storage condition was estimated. Mannitol and loctose were the most stable additives. Theses results suggest that the OD value of Ty21a growth, low temperature, mannitol and lactose are important factors for the optimal freeze-drying rate, the stable storage and the most stable additives, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.111-116
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• 1982

For the effective utilization of the fish resources in coastal regions, investigations on processing conditions of frozen-dried product, quality stability of the Product during storage, and utilization as a food material were carried out with the filefish, Navoden modestus. The processing condition was determined with the moisture content and texture of the product. The duality of the product was evaluated on chemical composition, rehydration capacity, TBA value, browning, omission test and sensory score. The conditions for the processing of frozen-dried filefish under the conditions of freezing temperature at $-10^{\circ}C$ and forced air thawing at $56{\pm}2^{\circ}C$ with a velocity of 1 m/sec were as follows : freezing temperature, $-10^{\circ}C$ : freezing time, 10 hours; thawing time, 2 hours ; and repeated number of freezing and thawing, 5 times. The yield, the condition of moisture and protein were $10.2\%,\;23.6\%\;and\;70.6\%$, respectively. The frozen-dried product packed with air and stored at room temperature showed no remarkable changes in TBA value, rehydration capacity, browning during the storage period of 90days. The frozen-dried filefish showed no remarkable differences in the taste, odor and texture, comparing with frozen-dried Alaska pollack on the market.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.413-418
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• 2002

The dough was frozen either before or after fermentation at the five different freezing and storage conditions. Although fermentation before freezing was effective for rapid freezing, it reduced bread volume of the dough frozen at both air freezer and liquid immersion freezer. Freezing at the air freezer set to $-70^{\circ}C$ took more time for freezing and resulted in lower bread volume than freezing at the immersion freezer set to $-20^{\circ}C$. Therefore, the freezing in the liquid immersion freezer was more effective to reduce the freezing time and increase the bread volume. At the liquid immersion freezer, the higher temperature was more effective than lower temperature. The doughs frozen in a liquid immersion freezer set to $-10^{\circ}C$ and fermented after de-frosting produced higher bread volume than control unfrozen dough. And also there was no significant difference in bread volume between the control unfrozen dough and the dough frozen in a liquid immersion freezer set to $-10^{\circ}C$, fermented before freezing and re-fermented after defrosting. The longer proof time and greater loaf volume obtained for the dough frozen and stored at the air freezer set to $-70^{\circ}C$. Therefore the optimum process for freezing the dough was freezing immediately after mixing, storing at $-10^{\circ}C$ in a liquid immersion freezer and fermented after defrosting.

• Journal of Food Hygiene and Safety
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• v.10 no.2
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• pp.97-102
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• 1995

For improved preservation of boiled-dried anchovies, the current preservation method of corrugated-cardboard box packaging and freezing below -18$^{\circ}C$ was compared to the nylon/polyethylene(NY/PE) packaging along with cooling temperature ranging from 5$^{\circ}C$ to 1$0^{\circ}C$ as well as ambient condition for eight months by determining physicochemical quality of stored samples. Lipid oxidation of stored anchovies and their browning increased with storage time. The phenomenon was delayed under the conditions of lower temperature and air-tight packaging. As quality-indicative criteria of stored anchovies, carbonyl value(r=-0.989), browning (r=-0.949) and color a value(r=-0.989), browning(r=-0.965), Hunter's color b value(r=-0.949) and color a value(r=-0.940) showed a highly-negative correlations with organoleptic qualities of the samples. Based on the above results, air-tight packaging in a laminated film and subsequent storage at cooling temperature was found to be a possible alternative to the current freezing-storage of boiled-dried anchovies from the physicochemical point of view.