• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.370-374
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• 1999

This study was carried out to some properties and curring effect of drip obtained from frozen-thawed park loin ham belly and imported belly by thawing process at 4$^{\circ}C$. Moisture content and pH value of drips were 88.05~90.85% and 5,72~6.05 and do not show significant differences between each samples. Protein contents were 11.07, 8.85, 8,76 and8,13% in the drips from domestic pork loin, ham, belly and imported belly, respectively. Approximately 99% of the drip were constituted with moisture and protein in any part of domestic pork and imported belly. Glutamic acid proline glycine, alanine and lysine were the predominant amino acid in the drips. Curing process of the drip by nitrite increased the pH value and total amino acid content. The residual nitrite decreased during the period of curing and total plate counts in drip with nitrite did not reach 1$\times$105CFU/g until 7 days.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.4
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• pp.560-566
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• 2010

In this study, the effects of the chilling process after thawing on pork quality were investigated by comparing the physiochemical properties and palatability of the samples just after thawing(0-TP) and the other chilled at $2^{\circ}C$ for two days after thawing (2-TP). The samples used for this study were obtained from vacuum packaged frozen loin from crossbred black pigs reared on Jeju island, and frozen at $-20^{\circ}C$ for 1 month and 12 months, and then thawing them at $4^{\circ}C$ for 20 hours. In the case of loin that was thawed after freezing for 1 month, 2-TP showed a higher water holding capacity and myofibril fragmentation index, lower hardness and chewiness, as well as better juiciness and palatability than 0-TP. However, effects of chilling after thawing were not significant in the case of loin that had been frozen for 12 months.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.1021-1028
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• 2017

Objective: The objective of this study was to evaluate the effects of ageing time of lamb loins prior to freezing on technological characteristics and oxidation stability of coarse ground lamb loin sausage using in a model system. Methods: Lamb loins (M. longissimus lumborum, n = 25) were aged at $-1.5^{\circ}C$ for 0, 1, 2, 3, and 8 wk and then frozen for the remaining days (a total of 30 wk). The aged/frozen/thawed lamb loins were ground, and model sausages were formulated with 75% aged/frozen/thawed lamb loin, 25% water, 1.5% sodium chloride (NaCl) and 0.3% sodium tripolyphosphate. The pH and thaw/purge loss of aged/frozen/thawed lamb loins were evaluated, and protein functionality (protein solubility and emulsifying capacity), water-holding capacity and textural properties of model sausages were determined. Cooked model sausages were vacuum-packaged in a plastic bag and displayed under continuous fluorescent natural white light ($3^{\circ}C{\pm}1^{\circ}C$). Colour and lipid oxidation of the cooked model sausages were evaluated on 0 and 21 d of display storage. Results: Ageing prior to freezing had no impact on pH and purge/thaw loss of lamb loins and the colour of cooked sausages (p>0.05) made from the loins. Lamb loins aged for at least 3 wk prior to freezing numerically improved total and myofibrillar protein solubilities (p>0.05) and emulsion activity index (p = 0.009) of meat batter, but decreased cooking loss (p = 0.003) and lipid oxidation (p<0.05) of model sausages. Conclusion: This study suggests that post-mortem ageing of raw meat prior to freezing could improve water-holding capacity and lipid oxidative stability of sausage made from the meat.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.487-495
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• 2013

The vacuum packaged ham and loin from low-fat pork cuts were frozen at $-20^{\circ}C$ for 3 months and thawed. Then, the thawed meat was chilled at $3^{\circ}C$, and impacts of chilling period on changes in physical properties of raw meat and cooked meat were investigated. In the case of raw meat, the pH value, $L^*$ value, drip losses, water holding capacity and gumminess of ham increased significantly on the 4th day compared with the 0th day of chilling after thawing. However the cooking losses, hardness and chewiness decreased significantly. The loin showed a similar tendency on the 2nd day of chilling after thawing. In the case of cooked meat, changes in physical properties during chilling period after thawing showed a similar tendency as raw meat, but pH value, $L^*$ value and $a^*$ value did not show significant difference. The springiness and cohesiveness of both raw meat and cooked meat did not show significant difference during chilling period after thawing. The sensory tenderness of ham and loin improved significantly on the 4th day and 2nd day during chilling after thawing, respectively.

• Food Science of Animal Resources
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• v.42 no.2
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• pp.341-349
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• 2022

The objective of this study was to examine the effect of temperature abuse prior to cold storage on changes in quality and metabolites of frozen/thawed beef loin. The aerobic packaged samples were assigned to three groups: refrigeration (4℃) (CR); freezing (-18℃ for 6 d) and thawing (20±1℃ for 1 d), followed by refrigeration (4℃) (FT); temperature abuse (20℃ for 6 h) prior to freezing (-18℃ for 6 d) and thawing (20±1℃ for 1 d), followed by refrigeration (4℃) (AFT). FT and AFT resulted in higher volatile basic nitrogen (VBN) values than CR (p<0.05), and these values rapidly increased in the final 15 d. Cooking loss decreased significantly with an increase in the storage period (p<0.05). In addition, cooking loss was lower in the FT and AFT groups than in the CR owing to water loss after storage (p<0.05). A scanning electron microscope (SEM) revealed that frozen/thawed beef samples were influenced by temperature abuse in the structure of the fiber at 15 d. Metabolomic analysis showed differences among CR, FT, and AFT from partial least square discriminant analysis (PLS-DA) based on proton nuclear magnetic resonance (¹H NMR) profiling. The treatments differed slightly, with higher FT than AFT values in several metabolites (phenylalanine, isoleucine, valine, betaine, and tyrosine). Overall, temperature abuse prior to freezing and during thawing of beef loin resulted in accelerated quality changes.

• Food Science of Animal Resources
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• v.34 no.1
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• pp.115-121
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• 2014

This study explored the effects of water or brine (2% NaCl, w/v) immersion thawing combined with ultrasound treatment (40 kHz, 150 W) on the quality characteristics of pork. Ultrasound treatment of pork was conducted in two cold media (at $4^{\circ}C$), water and 2% (w/v) brine, respectively. Because the ultrasound treatment caused temperature increase in the media from $4^{\circ}C$ to $16^{\circ}C$, the qualities of pork thawed by ultrasound were compared with those thawed by immersion either in water or brine where the temperature was being maintained at either $4^{\circ}C$ (low temperature control) or $17^{\circ}C$ (high temperature control). The ultrasound treatment resulted in rapid thawing of pork where the thawing rate was similar to those thawed in the $17^{\circ}C$ media. For quality characteristics, ultrasound-treated pork in brine had an advantage of less cooking losses when comparing to the control. In particular, ultrasound treatment in brine exhibited the lowest shear force (or highest tenderness) among the freezing/thawing treatments. Although the ultrasound processing in brine caused discoloration of the pork, this thawing technique had potential to be applied as a commercial thawing technology for frozen foods.

• 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.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.723-729
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• 2013

In this study, the quality characteristics due to the influence of various thawing methods on electro-magnetic and air blast frozen beef were examined. The loin and round of second grade Hanwoo were sliced into 5-7 cm thickness and packed with aerobic packaging. The packaged beef samples, which were frozen by air blast freezing at $-45^{\circ}C$ and electro-magnetic freezing at $-55^{\circ}C$, were thawed by 4 thawing methods with refrigeration ($4{\pm}1^{\circ}C$), room temperature (RT, $25^{\circ}C$), cold water ($15^{\circ}C$), and microwave (2450 MHz). These samples were thawed to the point, which were core temperature reached $0^{\circ}C$. Analyses were carried out to determine drip and cooking loss, water holding capacity (WHC), moisture contents and sensory evaluation. Frozen beef thawed by microwave indicated a lower drip loss (0.66-2.01%) than the other thawing methods (0.80-2.50%). Cooking loss after electro-magnetic freezing indicated 52.0% by microwave thawing for round compared with 41.8% by refrigeration, 50.1% by RT, and 50.8% by cold water. WHC thawing by microwave with electro-magnetic freezing didn't showed any difference depending on the thawing methods, while moisture contents was higher thawing by microwave with electro-magnetic freezing than refrigeration (71.9%), RT (75.0%), and cold water (74.9%) for round. The texture of sensory evaluation for round thawed by microwave result was the highest than refrigeration (4.7 point), RT (6.4 point) and cold water (6.6 point), while sensory evaluation was no significant difference. Therefore, it was shown that microwave thawing is an appropriate way to reduce the deterioration of meat quality due to freezing.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.482-487
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• 1998

This study was carried out to investigate the effects of freezing temperature on quality of thawed beef loin. In case of thaw drip loss, the freezing of -3$^{\circ}C$ and -2$0^{\circ}C$ were higest by 3.4% to 30 days and by 1.8% to 60 days, respectively. And the thaw drip loss of -3$^{\circ}C$ freezing was more than -2$0^{\circ}C$ freezing. The cooking loss of water bath and pan boiling were increased significantly during freezing than the beginning of freezing, but were not different -3$^{\circ}C$ and -2$0^{\circ}C$. The salt soluble protein extractability was decreased during freezing, the -2$0^{\circ}C$ freezing was higher than -3$^{\circ}C$ freezing. The water soluble protein extractability of -3$^{\circ}C$ freezing was not significant different during freezing storage, that freezed at -2$0^{\circ}C$ was increased during freezing. The "L" value of the beginning of freezing was higher than during freezing, the "a" value was not different during freezing, and the "b" value during freezing was higher than the beginning of freezing. The myoglobin denatured percentage of the -3$^{\circ}C$ and -2$0^{\circ}C$ freezing were highest by 94.4% to 45 days and by 94.0% to 15 days, respectively. The shear force value during freezing was higher than the beginning of freezing, the myofibrillar fragmentation index was not significant different during freezing. The pH was increased to freezing 30 days, after that was decreased.ays, after that was decreased.