• Journal of Animal Science and Technology
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• v.49 no.3
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• pp.387-394
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• 2007

To investigate the effects of deboning time and muscle type of ham on quality characteristics of cooked press ham, a total of twelve pigs(barrow, 100±5kg) were slaughtered and split in half. The left side ham of carcasses was deboned immediately after slaughter whereas the right side ham was deboned after chilling for 24 hours at 4℃. Each of two muscles(SM; Semimembranosus, BF; Biceps femoris) was used to make a press ham. The pH of hot-boning muscles was significantly(p＜0.05) higher than that of cold- boning muscles, and the pH of SM samples was significantly(p＜0.05) higher than BF samples. Hot-boning muscles showed significantly(p<0.05) longer sarcomere length compared with cold-boning muscles. There was no significant difference in myoglobin(Mb) percentage between SM and BF muscles, but SM samples of hot-boning showed significantly(p<0.05) lower L* value compared to hot-boning BF samples. The lightness(L*) of hot-boning muscles was significantly(p<0.05) lower than that of cold-boning muscles. These results suggested that the dark color of hot-boning samples might be due to not only the high muscle pH but also the long sarcomere length without difference in Mb percentage. Hardness and gumminess of hot-boning press ham were significantly(p<0.05) lower than those of cold-boning samples. These results implied that color and pH of press ham did not affected by deboning time or muscle type of ham. However data suggested that texture and panel test of press ham might be improved by using hot-boned muscle due to long sarcomere length of raw meat.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.228-233
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• 2002

To investigate the effects of submersion aging in chilled water on tenderness and microbial growth of vacuum-packed beef, the semimembranosus muscles of Hanwoo (Korean cattle) was sampled at a commercial meat plant at 24 hrs postmortem. The samples were cut to 2.5 cm thick steaks and randomly assigned to following two treatments. The samples were stored in conventional refrigerator at 4$^{\circ}C$ after vacuum packaging for control whereas the other vacuum-packed samples were submersed in chilled water at 1$^{\circ}C$ for treatment, and both samples were stored for 14 days to measure total plate counts (TPC), sarcomere length, free calcium concentration, shear farce value and myofibrillar fragmentation index (MFI). The sarcomere length of treatment was significantly (p<0.05) longer than that of control at 3 days aging. Result suggested that submersion in chilled water of vacuum-packed beef might be effective to improve tenderness of meat compared to storage in conventional refrigerator. There were no significant differences in the shear force and MFI between control and treatment during storage. However, the free calcium concentration of samples from treatment was significantly (p<0.05) higher than that of control at 7 days of ageing. This result indicated that the lower shear force value and the longer sarcomere length of samples from treatment might be due to increasing the free calcium ion concentration in sarcoplasm during storage. On the other hands, samples from control showed significantly (p<0.05) higher number of microbial (TPC) compared to treatment during storage. from results obtained, submersion in chilled water of vacuum-packed beef could be recommended as a desirable aging method to improve tenderness of Hanwoo compared to aging in conventional refrigerator.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.726-735
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• 2009

This study was conducted to investigate the Warner-Bratzler shear force (WBS), sarcomere length, total collagen contents and consumer tests of different cuts of Hanwoo beef based on quality grade. Five cuts [Cheggt (striploin), Dngsim (loin), Moksim (chuck roll), Udoon (top round), Yanggi (brisket)] were obtained from Hanwoo beef (bulls and steers, 24-30 months old) and grouped by their quality grades ($1^{++}$, $1^+$, 1, 2 and 3). The WBS values of chuck cut in $1^{++}$, $1^+$ and 1 quality grade groups were 5.47 (kg/0.5 $inch^2$), 5.46 (kg/0.5 $inch^2$) and 6.54 (kg/0.5 $inch^2$), respectively, which were significantly lower than those of chuck in quality grade 3, which was 8.41 (kg/0.5 $inch^2$) (p<0.05). The sarcomere length of the quality grade groups were significantly longer for brisket (3.72 ${\mu}m$) of $1^{++}$ quality grade than for that of 3 quality grade brisket (p<0.05). Brisket of $1^{++}$ and 2 quality grade had significantly greater sarcomere lengths than strip loin and top round in the same quality grade (p<0.05). The total collagen contents of strip loins in the $1^{++}$, $1^+$, and 1 quality grade groups (1.17, 1.18 and 1.14 g/100 g, respectively) were significantly lower than those of the 3 quality grade group (1.63 g/100 g) (p<0.05). The overall sensory scores of tenderness and juiciness for the five cuts of $1^{++}$ quality grade were significantly higher than those of the other quality grade (p<0.05). Among the five cuts, loin had the highest tenderness and juiciness scores (p<0.05), whereas top round had the lowest tenderness and juiciness scores (p<0.05). Overall, there were significant differences in the WBS and sensory properties among quality grades and cuts (p<0.05). However, the sarcomere length and total collagen contents of chuck roll, top round and loin did not differ among quality grades.

• The Korean Journal of Food And Nutrition
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• v.2 no.2
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• pp.21-26
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• 1989

The morphological changes of fresh beef treated with ficin(0.1% : 2 hrs, 6 hrs)were examined with transmission electron microscope(TEM), the results obtained were as follows ; Connective tissue protein in fresh beef treated with ficin became gradually fragmentation and was occurred solubilization with time The length of sarcomere in myofibrillar protein was elongated, M-line became dim, and the 1-band of Z-line was broken and beck me fragmentation with time.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.12
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• pp.1799-1808
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• 2006

This study was designed to explore the effects of marbling on meat quality characteristics and intramuscular connective tissue of beef longissimus muscle. Chemical determinations, histological and mechanical measurements were performed on the raw and cooked meat at d 4 postmortem. The results showed that crude fat, collagen, fiber diameter and maximum transition temperature of intramuscular connective tissue increased (p<0.05) with the increase of marbling score. The cooking losses, collagen solubility, WBSF and perimysial thickness decreased (p<0.05) with the increasing marbling. WBSF correlated (p<0.05) with moisture, crude fat, collagen, cooking losses, sarcomere length and perimysial thickness. The development of marbling results in the decline in cooking losses, the avoidance of sarcomere shortening, and the disorganization of the perimysia, which accounts for the improvement of beef tenderness.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.676-683
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• 2011

The aim of this study was to compare the physicochemical changes of hot-boned chicken breast and leg muscles. Chicken breast and leg muscles from 56 broilers were excised within a 15 min post-mortem (PM) and stored at $20^{\circ}C$. Physicochemical traits were determined at 0.5, 6, 12, and 24 h PM. The ultimate pH of leg muscle was higher than that of breast muscle (p<0.05). The content of glycogen in the breast muscle was relatively higher than that in the leg muscle until 6 h PM (p<0.05). R-values showing rigor mortis of breast and leg muscles were completed after or before 6 h PM. Breast muscle had less cooking loss than leg muscle (p<0.05). Drip loss did not significantly differ between breast and leg muscles with the exception of that at 6 h PM. The sarcomere length of leg muscle was relatively longer than that of breast muscle (p<0.05). The MFI of leg muscle was significantly lower than that of breast muscle (p<0.05). The shear force of leg muscle was lower than that of breast muscle at 6 and 12 h PM (p<0.05); however, that of both muscles did not significantly differ at 24 h PM.

• Food Science of Animal Resources
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• v.29 no.1
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• pp.55-61
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• 2009

The objective of this study was to examine the effects of high and low chilling temperature on the water-holding capacity (WHC) and tenderness of hot-boned breast meat of broiler chickens. Breast meat was obtained from 32 broiler chickens within 15 min post-mortem (PM), and then divided into two groups. One group was chilled at $-1^{\circ}C$ and the other group was stored at $30^{\circ}C$ for 3 hr, and then all the samples were chilled at $2^{\circ}C$ until 24 hr PM. During the storage, their physicochemical characteristics were tested at 15 min, 3 hr and 24 hr PM. These included pH, R-values, cooking losses, sarcomere length, MFI, and shear force of the breast meat, none of which was different (p>0.05) between the two temperature treatments at $-1^{\circ}C$ and $30^{\circ}C$. However, sarcomere length was shortened more at $-1^{\circ}C$ than at $30^{\circ}C$, MFI was larger at $30^{\circ}C$ than at $-1^{\circ}C$, drip loss was greater at $30^{\circ}C$ than at $-1^{\circ}C$, and WHC was lower at $30^{\circ}C$ than at $-1^{\circ}C$(p<0.05). In brief, in terms of yield and tenderness, broiler breast meat stored at $-1^{\circ}C$ was superior to that stored at $30^{\circ}C$.

• Food Science of Animal Resources
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• v.36 no.6
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• pp.819-828
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• 2016

Muscle fiber characteristics account for meat quality and muscle fibers are mainly classified into three or more types according to their contractile and metabolic properties. However, the majority of previous studies on bovine skeletal muscle are based on myosin ATPase activity. In the present study, the differences in the characteristics of muscle fibers classified by the expression of myosin heavy chain (MHC) among four bovine skeletal muscles such as longissimus thoracis (LT), psoas major (PM), semimembranosus (SM) and semi-tendinosus (ST) and their relationships to beef quality were investigated. MHCs 2x, 2a and slow were identified by LC-MS/MS and IIX, IIA and I fiber types were classified. PM, which had the smallest size and highest density of fibers regardless of type, showed the highest myoglobin content, CIE $L^*$, $a^*$, $b^*$ and sarcomere length (p<0.05), whereas ST with the highest composition of IIX, showed high shear force and low sarcomere length (p<0.05). The correlation coefficients between muscle fiber characteristics and meat quality showed that type IIX is closely related to poor beef quality and that a high density of small-sized fibers is related to redness and tenderness. Therefore, the differences in meat quality between muscles can be explained by the differences in muscle fiber characteristics, and especially, the muscles with good quality are composed of more small-sized fibers regardless of fiber type.

• Animal Bioscience
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• v.34 no.11
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• pp.1849-1858
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• 2021

Objective: Tenderness is a very complex feature, and the process of its formation is very complicated and not fully understood. Its diversification is one of the most important problems of beef production, as a result beef aging is widely used to improve tenderness as it is believed to provide a homogeneous product to consumers. While few studies have evaluated the muscle structure properties in relation to tenderness from early post-mortem, there little to no information available on how the muscle nanostructure of beef carcasses changes during post-mortem ageing to determine the appropriate aging time for acceptable tenderness. Methods: Muscle nanostructure (myofibril diameter [MYD], myofibril spacing [MYS], muscle fibre diameter [MFD], muscle fibre spacing [MFS], and sarcomere length [SL]), meat tenderness and cooking loss [CL]) were measured on 20 A2 longissimus muscles of Bonsmara, Beefmaster, Hereford, and Simbra at 45_mins, 1, 3, and 7 days post-slaughter. Muscle nanostructure was measured using a scanning electron microscope, while tenderness was measured using Warner Bratzler shear force. Results: At 45 minutes post-slaughter, breed affected MYD and MYS only, while at 24_hrs it also affected MFD and MFS. On day 3 breed effected MFS and SL, while on day 7 breed effected tenderness only. As the muscles matured, both MYD and MYS decreased while CL increased, and the muscles became tender. There was no uniformity on muscle texture features (surface structure, fibre separation, muscle contraction, and relaxation) throughout the ageing period. Conclusion: Meat tenderness can be directly linked to breed related myofibril structure changes during aging in particular the MYD, spacing between myofibrils and their interaction; while the MFD, spacing between muscle fibres, SL, and CL explain the non-uniformity in beef tenderness.

• Animal Bioscience
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• v.34 no.4
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• pp.743-750
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• 2021

Objective: The objectives of this study were to explore the expression patterns of myosin heavy chain (MyHC) genes of different skeletal muscles from Chinese cattle, and to investigate the relationship between myofiber characteristics and meat quality of M. longissimus lumborum (LL), M. psoas major (PM), and M. semimembranosus (SM) from Chinese Luxi and Qinchuan cattle. Methods: Three major muscles including LL, PM, and SM from Chinese Luxi cattle and Chinese Qinchuan cattle were used in this study. The myofiber characteristics were measured by histochemical analysis. The MyHC isoforms expression was evaluated by real-time quantitative polymerase chain reaction. Quality traits including pH value, meat color, cooking loss, Warner-Bratzler shear force (WBSF) and sarcomere length were determined at day 5 postmortem. Results: PM muscle had higher pH value, a* value, sarcomere length and lower WBSF value compared to LL and SM muscles (p<0.05). Numbers of type I myofiber and the relative expression of MyHC I mRNA in PM muscle were higher than those of LL and SM muscles (p<0.05). Myofiber diameter of PM muscle was lower than that of LL and SM muscles, regardless of myofiber types (p<0.05). Conclusion: According to the stepwise linear regression analyses, tenderness was influenced by myofiber characteristics in all three examined muscles. Tenderness of beef muscles from Qinchuan and Luxi cattle could be improved by increasing numbers of type I myofiber.