• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.660-666
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• 1997

Changes of chemical and nutritional composition were investigated in low salt-dried Yellow corvenia muscle during frozen storage at $-20^{\circ}C$. Moisture contort of Yellow corvenia was not significantly changed until after 5 months frozen storage. Salinity was $0.28\%$ in fresh Yellow corvenia and $2.30\%$ in the salted sample. Acidity of the fish muscle was increased in excess of 5 months storage. TBA value was increased by a little amount untel 1 month of storage and significantly incraeased in 3 months of storage. Free fatty acid was increased during frozen storage with rapid increase up to 1 month storage. VBN was increased after 1month storage and amino type nitrogen was increased in 5 months of storage. Major free amino acids were glutamic acid, alanine, glycine and lysine, and composition ratio of most free amino acids were not changed untel after 5 months storage. Polyenoic acid contents were decreased after storage and major fatty acids were palmitic acid (16 : 0), stearic arid (18 : 0) and major fatty acids were palmitic acid (16 : 0), stearic acid (18 : 0) and docosahexaenoic acid (22 : 6). From the results of chemical experiments, low salt-dried yellow corvenia would not be stored at $20^{\circ}C$ for more than 5 months.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.335-340
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• 2000

The objectives of this research were to investigate changes in characteristics of whole frozen soft persimmon during storage, and to evaluate effects of blanching and addition of ascorbic acid on the quality of frozen soft persimmon puree. Reducing sugar, soluble solids and carotenoids contents in frozen soft persimmon did not change significantly during storage, while ascorbic acid of whole frozen soft persimmon and puree was continuously decreased during 8 months of storage. Whole frozen soft persimmon thawed at low temperature or by microwave oven did not show remarkable quality differences, whereas thawing puree resulted in a drastic decrease in consistency. Addition of ascorbic acid to puree reduced browning discoloration, but blanching puree caused significant loss of color and increase of consistency.

• Animal Bioscience
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• v.35 no.8
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• pp.1270-1278
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• 2022

Objective: The objective of this study was to evaluate quality characteristics of reduced-salt pork sausage (PS) using pre-rigor muscle compared to those of regular-salt PS. In addition, effects of freezing on sausage batter with different temperatures (-30℃ vs -70℃) on quality characteristics of both sausage batter and cooked sausages during frozen storage were observed. Methods: Pre-rigor and post-rigor pork hams were used to manufacture low-fat sausages. Sausages using post-rigor (Post) muscle were manufactured at a salt level of 1.5%, whereas those with pre-rigor (Pre) muscle were processed at salt level of 1.0%. After these muscles were made at two salt levels (1.5% salt, Post-rigor; 1.0% salt, Pre-rigor), Sausage batters were stored at two frozen temperatures (-30℃ vs -70℃). During storage for 12 wks, they were measured for physicochemical and textural properties every 4 wks up to 12 wks. Results: pH values and temperatures of sausage batter of pre-rigor muscle were higher than those of post-rigor muscle regardless of the frozen temperature. The lightness and yellowness values of batter at the initial storage were the highest during storage. For PS, there were no differences in most parameters measured among all treatments. However, expressible moisture values (%) of Pre-30 and Pre-70 were lower than those of Post-30 (p<0.05). Conclusion: Regardless of frozen temperature during storage, quality characteristics of pre-rigor PS with salt level of 1.0% salt were similar to those of post-rigor PS with salt level of 1.5%. By using the pre-rigor muscle, salt content could be reduced by one third of the regular-salt level (1.5%) of post-rigor muscle.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.389-393
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• 1991

The changes in Physical properties of egg yolk(refractive index 43) as affected by salt content(7%, 10%, 13%) during frozen storage and their effects on functionalities in mayonnaise preparation were investigated. As the frozen storage period of salted egg yolk increased, viscosity was increased, and further increased with higher salt content, and emulsification capacity was gradually decreased. In case of egg folk with 7% salt, emulsification capacity was considerably decreased during the storage at $-25^{\circ}C$ over 4 months. Microbes of salted egg yolk were decreased with frozen storage, but the difference was not due to salt content. Mayonnaise. Prepared with frozen egg yolks stored for $2{\sim}3$ months, maintained a minimum viscosity. Viscosity became higher in the mayonnaise which prepared with egg yolk of higher salt content stored at $-25^{\circ}C$. Oil particle size of mayonnaise with the yolk contained more salt was smaller, when the yolk was stored at $-25^{\circ}C$ than $-15^{\circ}C$. Noticible microbes were detected in the mayonnaise right after preparation, but not detected in the mayonnaise after 1 month storage.

• Food Science of Animal Resources
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• v.35 no.1
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• pp.27-34
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• 2015

The ultrastructure in the beef muscle of the electro-magnetic resonance and air blast freezing during the frozen storage, and the changes in the quality characteristics after thawing were evaluated. The size of ice crystal was small and evenly formed in the initial freezing period, and it showed that the size was increased as the storage period was elapsed (p<0.05). The beef stored by the electro-magnetic resonance freezing showed the size of ice crystal with a lower rate of increase than the air blast freezing during the frozen storage. The thawing loss of beef stored by the electro-magnetic resonance freezing was significantly lower than the air blast freezing during frozen storage (p<0.05), and it showed that the thawing loss of the round was higher than the loin. Water holding capacity decreased as the storage period became longer while the electro-magnetic resonance freezing was higher than the air blast on 8 month (p<0.05). As a result of sensory evaluation, the beef stored by the electro-magnetic resonance freezing did not show the difference until 4 months, and it showed higher acceptability in comparison with the beef stored by the air blast freezing. Thus, it is considered that the freezing method has an effect on the change in the ultrastructure and quality characteristics of the beef.

• Food Science and Preservation
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• v.5 no.4
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• pp.320-325
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• 1998

Effects of blanching and salting for the pretreatment during frozen storage condition were investigated and optimized the salting condition on the activities of peroxidase and lipoxygenase, the stability of vitamin C and color, moisture content and hardness in immatured soybean. Before frozen storage, pretreatment processing is necessary to extend the shelf-life of vegetables. Salting condition of 2% for 180min treatment led to maximum inactivation of both lipoxygenase and peroxidase while blanching can more inactivate for lipoxygenase. Salting at 2% for 180min resulted in the highest amount of vitamin C remaining in the immatured soybeans after 6 months storage. The color of the immatured soybeans were severely changed after 6 months storage, while the color of salted soybeans at 3% and 180min treatment was similar to fresh products. Moisture content and hardness were reduced with addition of salt.

• Animal Bioscience
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• v.35 no.3
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• pp.494-502
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• 2022

Objective: The objective of this study was to evaluate functional properties of reduced-salt pork meat products made of pre-rigor pork loin treated by different freezing temperatures (-30℃ and -70℃) during storage. Methods: Pre-rigor cured pork loin with 1.0% added salt was compared to post-rigor muscle added with 1.5% salt for pH, color (L^*, a^*, b^*), cooking loss (CL), expressible moisture, warner-Bratzler shear value, thiobarbituric acid reactive substances (TBARS), and volatile basic nitrogen (VBN). Results: Pre-rigor cured pork loins had higher pH and temperature than post-rigor ones as raw meat (p<0.05). pH values were higher for pre-rigor pork loins than those of post-rigor pork loins (p<0.05). Color values did not different among treatments (p>0.05). No color differences were observed during storage period after cooking (p>0.05). The CL (%) of pre-rigor cured pork loins was the lowest when frozen at -70℃. The TBARS and VBN increased from 8 weeks of storage (p<0.05), but no further changed thereafter (p>0.05). Pre-rigor cured pork loins added with 1.0% salt showed similar characteristics to post-rigor pork loins added with 1.5% salt. Conclusion: Cured pork loins could be produced using pre-rigor muscle added with 1/3 of the original salt level (1.5%) and could be stored for up to 4 wks of frozen storage, regardless of a frozen temperature of -30℃ or -70℃ without detrimental effects.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.190-194
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• 2001

This study was carried out to investigate the possibilities of using xanthangum, guargum and ${\kappa}-carrageenan$ as cryoprotectant by examining changes in water content, specific volume, and hardness of bread made from the doughs with gums at $-20^{\circ}C$ freezing chamber for 12 weeks. The specific volume of bread decreased with time. It decreased more sharply in the control. The bread with lowest specific volume had the highest value in the hardness. The bread with ${\kappa}-carrageenan$ showed the lowest value in the hardness. In the water-holding capacity of frozen dough, the bread with ${\kappa}-carrageenan$ had the highest value, and ${\kappa}-carrageenan$ was effective in the protection of the degradation in the quality of the frozen dough during the frozen storage. In the sensory evaluation, texture, color and appearance of the control and the breads with gums did not show the difference for 1 week, but the breads with gums showed the higher score than control in sensory characteristics in the frozen storage for 12 weeks. The bread with ${\kappa}-carrageenan$ showed the highest sensory score during the frozen storage. These results were summarized that ${\kappa}-carrageenan$ was most effective in the protection from the degradation of the quality of frozen dough during the frozen storage.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.96-102
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• 2013

The possibility of instrumental differentiation of duck breast meat treated with different processing and storage conditions was investigated for industrial application. Duck breast meats, which were 1) refrigerated (fresh) after slaughter, 2) fresh but applied the torching process for the removal of remaining feathers (fresh-torched), and 3) frozen and thawed (frozen-thawed), were prepared and the torrymeter value and other quality factors were assessed. The torrymeter values of both duck breast meat and skin showed the lowest in frozen-thawed sample during the whole storage period. The drip loss of frozen-thawed sample was higher than those of fresh or fresh-torched ones. The number of total aerobic bacteria was lower in fresh-torched than fresh but both were not different from frozen-thawed at day 1 while no difference found thereafter. Sensory score of frozen-thawed sample was the lowest. The correlation analysis among the torrymeter value and quality factors of duck breast meat revealed that the torrymeter value is closely related with the total aerobic bacterial number, lipid oxidation, drip loss, and storage period but not with color. The results indicate that once the duck breast meat was frozen then thawed, drip loss and sensory quality can be affected and the torrymeter value can differentiate frozen-thawed from fresh and freshtorched duck breast meat.