• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.590-594
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• 2018

We developed a time-temperature indicator (TTI) that rapidly determines whether frozen mackerel Scomber japonicus has thawed during its distribution. Our TTI was made from filter paper capable of absorbing mackerel exudate that was soaked in a 20% citric acid solution at pH 4.0 and then dried. The dried absorbent paper was cut and attached to blue litmus paper with a 2 mm overhang. The fixed litmus paper was covered with a polypropylene film and sealed. The indicator was placed inside a polyvinyl vacuum package containing the mackerel sample. The vacuum-sealed packaged was frozen at $-20^{\circ}C$ for 24 h. After freezing, the color change and time dependence of the indicator were observed at room temperature ($25^{\circ}C$) and demonstrated the utility of this TTI for rapidly determining whether frozen mackerel underwent thawing during distribution.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.212-215
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• 2008

The effect of gamma irradiation on the Hunter color values, microbiological quality, and sensory attributes of frozen ground beef, pork, and chicken was investigated. Fresh meat samples were purchased from local markets, packed and frozen in polyethylene bags, and irradiated at 5 kGy. The Hunter's L-values (lightness) were not significantly different in all the meat samples after irradiation, but the a-values (redness) were higher in the irradiated beef and pork than the non-irradiated ones. After 6 months of storage at $-6^{\circ}C$, the L-values increased in all the meat samples and the a-value in chicken was lower in the irradiated sample than that of the control. The microbial counts decreased in all the samples right after irradiation, but the coliforms and yeasts & molds increased by 1-2 log cycles after 6 months even under frozen state. The overall acceptability of the meat was not affected by irradiation. Panelists had a higher likeness for the increased redness in irradiated beef. In general, only the color changes in meat as a result of irradiation were found to be species-dependent.

• 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 food and cookery science
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• v.27 no.1
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• pp.11-19
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• 2011

In this study, the physicochemical properties of buckwheat flour and quality characteristics of brown-rice doughs containing various concentrations of buckwheat flour stored at $-18^{\circ}C$ for 4 weeks and fermented were studied. The total polyphenolic contents, electron donating ability (EDA) of 0.5%, gelatinization onset temperature (To), gelatinization peak temperature (Tp), and gelatinization conclusion temperature (Tc) of buckwheat flour were 1,920.10mg%, 6.95%, $70.11^{\circ}C$, $78.21^{\circ}C$, and $84.05^{\circ}C$, respectively. There were no significant differences in the amount of yeast between brown-rice Jeung-pyun dough samples containing different levels of buckwheat flour and stored for different time periods. The amounts of carbon dioxide gas evolved from the brown-rice doughs were increased by increasing the concentration of buckwheat flour. The pH of brown-rice dough samples decreased with increasing storage period. Therefore, frozen brown-rice dough containing 6-15% buckwheat flour and stored for 3 weeks were the most desirable.

• Food Science of Animal Resources
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• v.32 no.3
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• pp.263-267
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• 2012

Six different types of biltong samples were manufactured from beef which was slowly frozen, quickly frozen or unfrozen. After marinating the samples according to the formulation used, meats were dried at two different temperatures ($28{\pm}1^{\circ}C$ or $42{\pm}1^{\circ}C$) until they lost half of their weights. Chemical, instrumental textural and sensorial analyses were done for determination of the most preferred sample and to compare the attributes of the samples with each other. It was found that, aw values of the samples were among 0.81 and 0.83, whereas water contents were changing among the values 39.64% and 45.37%. There were no significant differences determined among the protein contents of the biltong samples (p>0.05). Fat, ash and salt contents of the samples were among the values 1.32% and 2.07%, 5.30% and 6.06%, 2.68% and 3.30% respectively. Hardness of the samples were found between 34.81 N and 44.13 N and there was no significant difference observed among the hardness values of the biltong samples (p>0.05). As results of the analyses, it can be concluded that the highest flavor, color, tenderness and overall acceptability scores were obtained for the sample QF-LT which was made from quickly frozen beef and was dried at low temperature ($28{\pm}1^{\circ}C$) (p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.489-494
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• 1998

For the purpose of improving the qualities of popcorn, potato, frozen hotdog and steamed egg, the effects of food height(0mm: HO, 5mm: H5, 10mm, 15mm: H15) for microwave cooking on physicochemical properties were investigated. In popcorn, weight loss was decreased as height increased while volume of popcorn was increased, which indicated that popcorn was poped very well as height increased. H10 showed the highest taste score in sensory evaluation. In potato, degree of gelatinization was increased as hight increased. H10 showed the highest overall acceptance score. In frozen hotdog, hardness of hotdog was decreased as hight increased and H15 showed the lowest hardness score (408.8g). In steamed egg, H5 showed the highest temperature and H10 showed the highest overall acceptance score. Physicochemical properties of food were changed by heating height of microwave heating.

• Food Science and Preservation
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• v.30 no.6
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• pp.983-990
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• 2023

This study was conducted to develop a preservation technology that can induce changes in physicochemical properties to effectively utilize of persimmon leaves. The application effects of steaming or freezing technique were investigated. Astringent persimmon leaves were steam-blanched (100℃, 30 sec) or frozen (-20℃, 15 d), followed by hot-air drying (50℃). The physicochemical properties of the extract obtained by hot-water leaching from the dried leaves were compared. The extract of leaves dried without pretreatment was used as a control. L* value was higher in steamed than in control and frozen. a* value was highest in the control. The browning index was higher in the frozen and lower in the steamed than in the control. Soluble solids were the highest in the steamed and the lowest in the frozen. Sucrose content was relatively high in the steamed, and the glucose and fructose contents were relatively high in the frozen. Total polyphenol content and DPPH radical scavenging activity were higher in steamed and lower in frozen than in control. Thus, it was confirmed that steam or freeze pretreatment after harvesting persimmon leaves affects the extraction yield, color, antioxidant capacity and component changes of dried persimmon leaves. Unlike steaming, freezing pretreatment showed the effect of promoting decomposition and browning reactions, and it is considered useful when such an effect is needed.

• Food Science of Animal Resources
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• v.32 no.4
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• pp.396-403
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• 2012

This study was conducted in order to investigate the effect of storage temperature abuse on the freshness of refrigerated and frozen spent hen's meat. After a room temperature storage condition, two different storage temperature were followed: refrigeration and frozen storage. All parts of the spent hen's meats were thawed at 4 d intervals up to 3 times (2, 6, and 10 d) for 24 h. The level of bacteria on the different parts of the refrigerated and frozen meats was higher than 6 Log CFU/g under the following storage conditions: refrigerated - breast, 12 h; leg, 6 h; wing, 12 h at the $1^{st}$ analysis, frozen - breast, 12 h at the $2^{nd}$ analysis; leg, 24 h at the $1^{st}$ analysis; wing, 12 h at the $1^{st}$ analysis. The pH value for the leg meat was higher than breast and wing meats. In the color measurements, under the room temperature storage condition, lightness and redness values decreased but the yellowness increased in refrigerated meats (p<0.05). The K-value regarding refrigerated leg meats exceeded 60%, which is the threshold value to evaluate the degree of freshness, during the $1^{st}$ analysis (p<0.05). The VBN value of refrigerated leg meat was the highest and reached up to 96.93 mg%. Thus, studies regarding the possible decline in quality according to the change of storage temperature could be used in order to establish a basic database for the quality control of spent hen meat being traded with other countries.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.197-201
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• 2006

Long-term storage technology was developed to extend shelf-life of citron (Citrus junos). Changes in quality characteristics of blanched and frozen citron peels (type A, without blanching for control; type B, blanched at $95^{\circ}C$ for 2 min; type C, blanched at $95^{\circ}C$ for 2 min, sugar added; type D, blanched at $95^{\circ}C$ for 5 min) during frozen storage were evaluated. Citron jam was prepared using frozen citron sample B, which showed the highest quality characteristics during storage, and high quality characteristics, such as yield and overall acceptability, were obtained when using 40% frozen citron, 41% sugar, 18.56% glutinous starch syrup, 0.39% pectin, and 0.05% citric acid. During storage of both blanched and frozen citron peels and citron jam made of frozen citron peel, changes in characteristics such as pH, total acids, soluble solids, and browning, were lower than those of control. Sensory evaluation for sourness, sweetness, and overall acceptability of citron jam made with frozen citron peel during storage showed higher values than those of control.