• The Korean Journal of Food And Nutrition
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• v.8 no.2
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• pp.93-104
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• 1995

Effect of frozen storage(0, 15, 30, 40 days, -18$^{\circ}C$), cooking methods(frying, microwaving) and reheating on lipid oxidation in chicken meats were evaluated by measuring thiobarbituric acid value (TBA value) and by measuring fluorescence value. TBA values were increased by storage days and were higher in leg meats than breast meats. According to cooking method, TBA values were higher in frying chicken meats. The fluorescence values were also increased by storage days and were higher in breast meats than leg meats.

• Korean Journal of Food Science and Technology
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• v.12 no.1
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• pp.34-40
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• 1980

In order to establish the frozen storage method of pork and contribute to the stabilization of pork price physicochemical changes and sensory evaluation of pork, stored at $-20^{\circ}C$ up to the period of 12 months, were analyzed every three months. The drip loss of frozen meat cuts was below 1% regardless of storage months. In the course of storage, pH of frozen half carcass rose a little, while that of meat cuts remained almost the same. WHC(water holding capacity) of frozen half carcass and meat cuts was in the range of $50{\sim}60\;and\;55{\sim}62%,$ respectively and VBN (volatile basic nitrogen) was about $11{\sim}18mg%,$ all of which did considerably change during the storage. TBA(thiobarbituric acid) value was not increased up to the 6th month of storage, but represented a considerable increase after the 9th month of storage, Both tenderness and juiciness of frozen pork were decreased after the 12th month of storage but the axxrptability of frozen pork to the consumers turned out fairly good.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.117-124
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• 1983

Qualify changes of the precooked frozen sardine (Sardinops melanosticta) during frozen storage were investigated by measuring extractable protein, expressible drip, available lysine and lipid oxidation as peroxide value. Fresh sardine was dressed, washed in chilled water, cooked in boiling water to have $55^{\circ}C\;and\;70^{\circ}$ at the center of the body, frozen at $-40^{\circ}C$, and finally stored at $-20^{\circ}C$ for 84 days. The quality factor mentioned above were determined in both ordinary and dark muscle at 14 day intervals through the period of storage. When cooked at $70^{\circ}C$, the changes in expressible drip were less than that of raw and the one cooked at $55^{\circ}C$. In observation of the extractability of muscle protein, no great change in extractable sarcoplasmic protein was observed, the extractable myofibrillar protein, however, showed a tendency to decrease during the period of frozen storage, accompanying the increase of the alkali-soluble protein. That was more excessive in ordinary muscle than dark muscle. Lipid oxidation of dark muscle was faster than that of ordinary muscle. Acid value was not changed, and peroxide value of the samples cooked at $70^{\circ}C\;and\;55^{\circ}$ was higher than that of raw at the early stage of the storage, after 40-50 day storage, it became lower than that of raw muscle.

• 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 the Korean Society of Food Culture
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• v.19 no.2
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• pp.209-216
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• 2004

To investigate physico-chemical changes of mashed red repper and red pepper powder during frozen storage, we analyzed the quality of samples after mashing, mashing and blanching, mashing and addition of vitamin C, mashing and addition of NaCl. The most important quality factor of red pepper is red color. $\alpha$ value of red pepper powder of Pochungchun was 31.51. These results showed that those processing methods were effective to preserve red color. Capsanthin contents of mashed red pepper treated with vitamin C were decreased 1.8% after 180 days of frozen storage. This decrease was the least, showing that addition of vitamin C helped retaining capsanthin contents. Capsaicin and dihydrocapsaicin contents in Pochungchun powder ore decreased 11.9 and 18.3% during frozen storage respectively. These results showed that capsaicin was more stable than dihycrocapsaicin during frozen storage. Generally capsaicin and dihydrocapsaicin in the Pochungchun red pepper frozen-stored after mashing were less decreased than red pepper powder, and addition of vitamin C to the mashed red pepper was the most effective to retain capsicin and dihydrocapsaicin than others. The content of vitamin C in the red pepper frozen-stored after masking and blanching was 12.0 mg/100g, compared with 44.0 mg/100g in the sample stored after only mashing. This suggested that blanching process destroyed vitamin C in the mashed red pepper. Addition of salt in the mashed red pepper showed the same inclination. But, addition of vitamin C to the mashed red pepper was decreased 32.9% compared with 69.0% in the mashed red repper during frozen storage. Theser results indicated that addition of vitamin C could retain vitamin C in the mashed red lopper.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.450-455
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• 1997

Scallop, Patinopecten yessonensis(Jay), cultivated in the cold east coast of Kwangwon region, Korea, is expected to be producted to about 50,000 tones in 2000 year. Freezing is one of the most effective methods applied for soraging seafoods. But, the domestic refrigerator with an automatic defrost system shows the temperature fluctuation during defrosting, thus might result in the deterioration of the frozen foods. In this study, the domestic refrigerator with an automatic defrost system, temperature fluctuation from -18 to -5$\pm$1$^{\circ}C$ and fluctuation intervals from 16 to 20 hr, was used for storing scallop. pH was decreased rapidly after 3 month storage, while the content of amino nitrogen was increased continuously. The TMA content of open state was increased very rapidly on 3 month storage and then increased slowly, whereas that of vinyl package increased slowly. The VBN content was increased almost constantly with no significant differences between storage methods. The TBA content was increased up to 3 month storage with the higher value in open state than vinyl package in the beginning periods of storage, and then decreased very rapidly. The number of total viable cell was increased continuously during storage with higher number in open state than vinyl package. The estimated shelf-lives of frozen scallop with open state and vinyl package stored at -18$^{\circ}C$ in the domestic refrigerator with an automatic defrost system were 3.55 and 3.78 months, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.139-148
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• 1985

Changes in fish jelly forming ability of pretreated and frozen common carp and conger eel were examined. Four kinds of pretreated samples were prepared such as round, mechanically separated meat using fishmeat separator, chopped and water washed meat and fish meat paste. The quality of pretreated samples and fish jelly products made from pretreated sample were generally in good condition for three months of frozen storage at $-30^{\circ}C$. Judging from fish jelly forming ability, the round state of common carp was superior to other pretreated samples during frozen storage. In case of conger eel, fish meat paste revealed totter jelly forming ability than any other pretreated samples during frozen storage.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.109-118
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• 2013

The objective of this study is to increase the utilization of duck by-products. The nutritional characteristics of four kinds of duck by-products (liver, heart, gizzard, and feet) were determined. The quality changes of four kinds of duck by-products were evaluated during frozen storage at $-20^{\circ}C$. The crude protein and cholesterol contents showed the highest level in liver while the crude fat content was determined to be the highest content in feet at 13.90%, and lowest in gizzard at 0.57%. Duck by-products contained USFA in the range of 48.69-77.66%, and the highest level in feet (p<0.05). During storage of duck by-products at $-20^{\circ}C$, the pH of duck by-products was in the range of 6.24-7.15, and there were no significant differences during the 4 mon storage period at $-20^{\circ}C$. Microbial counts of duck by-products except the gizzard were decreased significantly as storage time elapsed. In the sensory evaluation, overall acceptability of by-products (liver, heart, gizzard and feet) showed a tendency of decreasing value through storage, because off-flavor was increased with increased storage. Considering the combined results, one can conclude that duck by-products provide a good source of protein, and it was judged that the use of raw meat would be most appropriate within 3 mon of frozen storage.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.753-760
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• 2021

This study was carried out to discover suitable packaging methods during the cold or frozen storage of sawtooth oak and Japanese larch seedlings, which are major afforestation tree species in Korea. The weight loss rate of sawtooth oak was lower under frozen storage at -2℃ (maximum, 33.7%) than under cold storage at 2℃ (maximum, 61.0%). A film liner treatment inside the packaging box effectively suppressed the increase in the weight loss rate. For the sawtooth oak containerized seedlings, when stored at -2℃, the rate of weight loss was 17.9 to 25.4% in the untreated group and less than 1% in the film liner treatment group. Similar results were observed with Japanese larch. After two months of freezing at -2℃, both species maintained a low index of 1.0 - 1.1 with regard to the degree of shoot desiccation of containerized seedlings, and there was no significant difference between the treatments. On the other hand, the chlorine dioxide treatment could more effectively reduce the occurrence of mold and shoot desiccation than a PE single treatment in bare-root seedlings. According to these results, it was concluded that frozen storage is generally suitable as a means of long-term storage compared to cold storage of sawtooth oak and Japanese larch. A chlorine dioxide treatment at 20 ppm was effective for maintaining seedling quality levels during storage, demonstrating the good effect of suppressing the occurrence of shoot desiccation and the occurrence of mold.

• Korean journal of food and cookery science
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• v.17 no.2
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• pp.149-155
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• 2001

Namul cooked with the standard recipe was examined by research of microbiological test for three months and sensory evaluation of frozen namul after reheating. When the namul was freezed storage, in the microbiological test namul began to change on the 40th day, but there was no problem about stability of storage until 3 months. The overall qualities of taste, flavor, color and texture were examined by sensory evaluation of frozen namul after reheating. The pH was seemed to change slowly, its color was changed on the 20th day from the beginning of storage. Radish root represented substantial difference in texture and overall quality on the 20th day. The off-flavor of immature pumpkin stated on the 25th day. Later 10days nettle tree mushroom began to be changed in its taste, texture, overall quality and appearance, then on the 25th day it was seemed to have low preference. But oak mushroom kept its quality good for 25 days. Oyster mushroom was changed in color, appearance and overall quality on the 20th day. Bracken had low preference in taste, texture and moisture on the 25th day. The color of spinach was changed on the 15th day, and its taste on the 20th day. Soybean sprout was changed in taste, texture and overall quality on the 15th day, and overall quality marked low preference on the 25th day Root of bell flower was changed on the 25th day(p<0.05).