• Fisheries and Aquatic Sciences
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• v.13 no.3
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• pp.231-235
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• 2010

The effects of various natural antioxidant sources on oxidation of olive flounder (Paralichthys olivaceus) and fish diet during storage was determined. Juvenile fish were distributed among 18 flow-through tanks (40 fish per tank). Six experimental diets were prepared in triplicate: control (CT), antitox (AT), green tea extract (GE), fig extract (FE), Haeroc product (HP) and by-product of green tea (BG). The experimental diets were stored at two temperatures: room temperature ($26.8^{\circ}C$) for 14 days and frozen ($-30^{\circ}C$) for 16 weeks. Thirty fish were sampled from each tank at the end of the 8-week feeding trial. Whole bodies of fish were homogenized and stored in a home freezer ($-9.6^{\circ}C$) for 24 weeks. Acid values (AVs) and peroxide values (POVs) of the diets and frozen fish during storage were monitored. AVs of the experimental diets tended to increase with the storage period except for that of the HP diet at room temperature. POVs from FE, CT, and BG diets peaked at day 7 and then decreased through the remainder of the experiment. AVs of the experimental diets and fish increased with time at $-30^{\circ}C$ and $-9.6^{\circ}C$. Results of this study show that by-products of green tea and Haeroc product seem to have potential as antioxidants in fish feed to inhibit oxidation of both the feed and fish during storage.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.102-110
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• 2000

Peeled garlic was stored at $-18^{\circ}C\;and\;-40^{\circ}C$, respectively and changes in main quality factors during storage were determined for $15{\sim}16$ months. The puncture force measured by texturemeter was $2709{\pm}368$ G.S at the beginning of storage and did not change significantly after the 15 months storage. Drip losses of stored garlic were 0.4% and 0.7% at $-18^{\circ}C\;and\;-40^{\circ}C$, respectively. Major flavor compounds of garlic analyzed by GC and GC/MS, such as diallyl disulfide, 1,3-dithiane, diallyl sulfide, 2-butanal, were not changed in their quantity during the frozen storage. The contents of cysteine, valine and tyrosine increased slightly notwithstanding the storage temperature. Sucrose content slightly decreased, but glucose and fructose tended to increase in garlic stored at $-18^{\circ}C$. The content of pyruvic acid, degradation product of alliin, did not change during storage at both storage temperatures. These results indicated that peeled garlic could be stored at $-18^{\circ}C$ for longer than 15 months without quality problems.

• Journal of the Korean Society of Food Culture
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• v.36 no.1
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• pp.84-91
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• 2021

The oriental plum (Prunus salicina) is one of the most popular fruits in Korea due to its sweet taste and pleasant aroma. The objective of this study was to analyze the quality characteristics and antioxidant activities of a puree made using plums stored at low-temperatures. The quality characteristics were determined by estimating total soluble solids (TSS, °Brix), titratable acidity (TA, % citric acid), TSS/TA ratio, pH, colors, sugar content, and sensory profiles. The antioxidant effects were estimated by total polyphenol and flavonoid content and radical scavenging activity. The results showed that the plum puree containing both the flesh and the peel had markedly higher red coloration (a⁎ value) than the puree without the peel, while yellow coloration (b⁎ value) and lightness (L⁎ value) were lower in the puree without the peel than with the peel. The sensory qualities including the plum taste and flavor, texture as well as overall acceptance showed no significant variation between the samples. Meanwhile, the total polyphenol/flavonoid content and radical scavenging activities were significantly improved by the presence of fruit peel and by frozen storage. These findings suggest that frozen plums could be a suitable ingredient for making a puree and concentrate for the food manufacturing industry.

• 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.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.322-327
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• 2004

This study was carried out to evaluate the effect of flour's protein contents on the quality of Danish pastries made with frozen doughs. Danish pastries for frozen dough were made by straight dough method. Frozen doughs were stored for 12 weeks at -20$^{\circ}C$ and baked after thawing and fermentation a month. The volume, the moisture content, the texture and the quality evaluation of Danish pastries were investigated. The volume of Danish pastry decreased with the increase of frozen storage time. Danish pastry made by flour of 13.2% protein content showed larger volume than that made by flour of 9.2% protein content. The moisture content of Danish pastry revealed that there were no significant decrease with the increase of frozen storage time. In terms of hardness, Danish pastry made by flour of 9.2% protein content accomplished the best texture in the resulting pastry. On the quality evaluation, Danish pastry made by flour of 13.2% protein content had the highest score.

• Food Science and Preservation
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• v.23 no.7
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• pp.931-938
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• 2016

To evaluate the effect of freezing temperature on quality characteristics of dried persimmons, dried persimmons were frozen at $-50^{\circ}C$ (quick frozen, QF) and $-20^{\circ}C$ (slow frozen, SF) for 24 hr. Frozen persimmons were then stored at -20, -10, 0 and $10^{\circ}C$ for 80 days. Total free sugar content of SF persimmons was higher than those of QF in the $+10^{\circ}C$ and $-20^{\circ}C$ stored samples. Except for samples stored at $10^{\circ}C$, the CIE $L^*$ values for QF persimmons were higher than those for SF persimmons. For samples stored at $10^{\circ}C$ and $0^{\circ}C$, the CIE $a^*$ and $b^*$ values of SF samples were higher than those for QF samples. The texture of frozen dried persimmons was investigated to determine springiness, chewiness and hardness. Chewiness and hardness of samples held at $0^{\circ}C$ were higher in SF than in QF persimmons. However, when stored at $-10^{\circ}C$, chewiness and hardness were higher in QF than in SF samples. Springiness results were similar among the QF and SF persimmons held at different storage temperatures. For all storage temperatures, QF persimmons had a high soluble tannin content. All of the sample, the average soluble tannin contents of QF is 236.09 mg%. On the other hands, those of SF is 226.87 mg%. The results indicate that freezing rate and holding temperatures have significant effects on dried persimmon texture, soluble tannin level, and free sugar content. Further studies that include sensory evaluations are needed to determine the optimum freezing rate and holding temperature for dried persimmons.

• Food Science and Preservation
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• v.24 no.2
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• pp.168-180
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• 2017

This study was performed to determine the rapid thawing method for reducing the thawing time of frozen pork loins and to examine the effects of supercooling on the microbiological, physicochemical, and sensory qualities of fresh and frozen-thawed pork during storage at -1.5, 4, and $15^{\circ}C$. Forced-air thawing at $4^{\circ}C$ was the most time-consuming process, whereas radio frequency thawing time was the shortest by dielectric heating. The supercooling storage temperature was chosen to be $-1.5^{\circ}C$ because microstructural damages were not observed in the pork sample after cooling at $-1.5^{\circ}C$ for 24 h. Fresh or frozen-thawed pork loins stored at $-1.5^{\circ}C$ had lower drip loss and total volatile base nitrogen, thiobarbituric acid-reactive substance, and Hunter b* levels than loins stored at 4 and $15^{\circ}C$. In addition, the least degree of increase in preexisting microorganisms counts of the fresh or frozen-thawed pork loin samples was obtained during supercooled storage at $-1.5^{\circ}C$. Sensory quality results of fresh and frozen-thawed pork loin samples stored at $-1.5^{\circ}C$ showed higher scores than the samples stored at 4 and $15^{\circ}C$. These data indicate that supercooling at $-1.5^{\circ}C$ in the meat processing industry would be effective for maintaining the quality of pork meats without ice crystal nucleation and formation.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.697-704
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• 1999

To investigate the combination effects of natural preservatives such as rosemary extract and ${\alpha}-tocopherol$, and vacuum packaging method on the shelf-life of herring (Clupea pallasi) fillet during cold and frozen storage, quality attributes including moisture content, pH, K-value, volatile basic nitrogen (VBN), viable cell count, peroxide value (POV) and color value were analyzed. Good qualities of the samples with air and vacuum packaging stored at $4^{\circ}C$ were maintained at least for 3 days (control; one day in air) and for 7 days (control; 3 days in vacuum), and those of the samples stored at $-20^{\circ}C$ were for 90 days (control; 80 days in air, 90 days in vacuum), while those of the samples stored at $20^{\circ}C$ deteriorated in one day.

• Journal of Korean Neurosurgical Society
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• v.57 no.4
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• pp.242-249
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• 2015

Objective : The timing of cranioplasty and method of bone flap storage are known risk factors of non-union and resorption of bone flaps. In this animal experimental study, we evaluated the efficacy of cranioplasty using frozen autologous bone flap, and examined whether the timing of cranioplasty after craniectomy affects bone fusion and new bone formation. Methods : Total 8 rabbits (male, older than 16 weeks) were divided into two groups of early cranioplasty group (EG, 4 rabbits) and delayed cranioplasty group (DG, 4 rabbits). The rabbits of each group were performed cranioplasty via frozen autologous bone flaps 4 weeks (EG) and 8 weeks (DG) after craniectomy. In order to obtain control data, the cranioplasty immediate after craniectomy were made on the contralateral cranial bone of the rabbits (control group, CG). The bone fusion and new bone formation were evaluated by micro-CT scan and histological examination 8 weeks after cranioplasty on both groups. Results : In the micro-CT scans, the mean values of the volume and the surface of new bone were $50.13{\pm}7.18mm^3$ and $706.23{\pm}77.26mm^2$ in EG, $53.78{\pm}10.86mm^3$ and $726.60{\pm}170.99mm^2$ in DG, and $31.51{\pm}12.84mm^3$ and $436.65{\pm}132.24mm^2$ in CG. In the statistical results, significant differences were shown between EG and CG and between DG and CG (volume : p=0.028 and surface : p=0.008). The histological results confirmed new bone formation in all rabbits. Conclusion : We observed new bone formation on all the frozen autologous bone flaps that was stored within 8 weeks. The timing of cranioplasty may showed no difference of degree of new bone formation. Not only the healing period after cranioplasty but the time interval from craniectomy to cranioplasty could affect the new bone formation.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.624-631
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• 1996

Effect of fluctuation range and intervals of defrosting temperature on quality of frozen foods stored in a domestic refrigerator equipped with an automatic defrost system was evaluated. As defrost system was operated, temperatures of domestic refrigerators were elevated from $-18^{\circ}C\;to\;-5^{\circ}C\;and\;-15^{\circ}C$, and fluctuation intervals were l6 hrs and 30 hrs, respectively. Quality deterioration such as protein denaturation, vitamin loss, exudate production and changes in appearance of frozen foods was minimized by reducing temperature oscillation during storage. Considerable effects of thermal oscillation on ice crystal sizes were observed for frozen beef tissue and ice cream. TTI (time temperature indicator) system also proved that the temperature control of defrost system in domestic refrigerator can improve the quality of foods during storage.