• Asian-Australasian Journal of Animal Sciences
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• v.33 no.12
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• pp.1999-2007
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• 2020

Objective: This study was aimed to investigate the muscle-specific beef color stability at normal and high ultimate pHs. Methods: The impact of muscle (Longissimus lumborum [LL] vs psoas major [PM]) and pH (normal ultimate pH [Np] vs high pH dark cutting beef [Hp]) on color stability, indicated by basic color traits, metmyoglobin reducing activity (MRA) and oxygen consumption (OC), as well as the lipid oxidation, were determined over 7 days of display at 4℃. Results: Hp-LL had the highest pH (6.92), followed by Hp-PM (6.01), Np-PM (5.76), and Np-LL (5.52). Hp-LL had increased (p<0.05) a^⋆, chroma and % oxymyoglobin during display. Hp-LL also had the highest metmyoglobin (MMb) reducing activity and OC among all the samples, thus, the greatest color stability, although very dark throughout storage, with lowest values for lightness (L^⋆) and yellowness (b^⋆). Np-LL also exhibited relatively high color stability, as a result of its lower % MMb and OC and higher MRA than psoas muscle samples. The 0.2 unit difference of the pH between Hp and Np psoas muscle, resulted in the difference of the color intensity, not the color stability. Interestingly, high pH psoas muscle (Hp-PM) did not have better color stability than Np-PM, and in fact had lower color stability than even Np-LL. The similar level of OC and lipid oxidation cannot explain the difference in color stability between Hp-PM and Np-LL. Conclusion: The Hp does not always show better color stability compared with Np beef, which depends on the muscle type. The balance of MRA and OC is important to keep the color in great intensity and stability in the meantime.

• Journal of Animal Science and Technology
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• v.58 no.6
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• pp.23.1-23.17
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• 2016

Background: The functionality of myofibrillar proteins is a major factor influencing the quality attributes of muscle foods. Nonetheless, the relationships between muscle type and oxidative changes in chevon during ageing are meagrely elucidated. Postmortem changes in antioxidant status and physicochemical properties of glycolytic gluteus medius (GM) and oxidative infraspinatus (IS) muscles in goats were compared. Methods: Twenty Boer bucks (9-10 months old, body weight of $36.9{\pm}0.725kg$) were slaughtered and the carcasses were subjected to chill storage ($4{\pm}0.5^{\circ}C$). Analyses were conducted on GM and IS muscles sampled on 0, 1, 4 and 7 d postmortem. Results: Chill storage did not affect the antioxidant enzyme activities in both muscles. The IS had greater (P < 0.05) superoxide dismutase and catalase activities than GM. Carotenoid and tocopherol contents did not differ between muscles but decreased (P < 0.05) over storage. The IS had higher (P < 0.05) glycogen and ultimate pH and lower (P < 0.05) shear force and cooking loss than GM. The carbonyl content, % metmyoglobin, drip loss and TBARS increased (P <0.05) while free thiol, metmyoglobin reducing activity (MRA), shear force and myoglobin decreased (P < 0.05) over storage. Muscle type had no effect (P > 0.05) on free thiol, MRA and TBARS. The GM had lower (P < 0.05) redness on d 0 and 1 than IS while the IS had greater carbonyl, % metmyoglobin and drip loss than GM on d 7. The reflective density of slow myosin heavy chain (MHC) was higher (P < 0.05) while the density of fast MHC and actin was lower (P < 0.05) in IS than GM. Regardless of muscle type, the density of MHC decreased (P < 0.05) while that of actin was stable over storage. Nonetheless, the degradation of fast and slow MHC was greater (P < 0.05) in IS than GM. Muscle type had no effect (P > 0.05) on consumer preference for flavour, juiciness and overall acceptability. However, IS had higher (P < 0.05) tenderness score than GM on d 1 and 4 postmortem. Intramuscular fat was higher (P< 0.05) in IS compared with GM. Fatty acid composition did not differ between the muscles. However, GM had lower (P < 0.05) n-6/n-3 ratio than IS. The n-3 and n-6 PUFA declined (P < 0.05) while the SFA increased (P < 0.05) over storage. Conclusion: The changes in myofibrillar proteins and physicochemical properties of goat meat during postmortem chill storage are muscle-dependent.

• Animal Bioscience
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• v.36 no.5
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• pp.785-796
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• 2023

Objective: We aimed to evaluate the color and oxidative stability of beef gluteus medius (GM) from cattle raised in organic and non-organic production systems. Methods: The GM samples (n = 10) were obtained from organic (ORG; n = 5) or nonorganic (NORG; n = 5) beef samples, sliced into 2.54-cm steaks, packaged in aerobic conditions, and stored for nine days at 4℃. ORG and NORG steaks were compared regarding myoglobin concentration, pH, instrumental color, delta E (ΔE), metmyoglobin reducing activity (MRA), and lipid oxidation on days 0, 5, and 9. Results: Feeding system did not influence (p>0.05) the myoglobin concentration. ORG steaks exhibited greater (p<0.05) meat pH, yellowness, and MRA, whereas NORG steaks exhibited greater (p<0.05) redness, chroma, R630/580, delta E, and lipid oxidation. ORG and NORG steaks exhibited similar (p>0.05) lightness and hue angle. During storage, ORG and NORG exhibited an increase in muscle pH, hue angle, and lipid oxidation; and a decrease (p<0.05) in redness, yellowness, chroma, and color stability (R630/580). Both samples exhibited a stable (p>0.05) pattern for lightness and MRA. Conclusion: Therefore, the production system can affect beef color and lipid stability during storage.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.2
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• pp.265-273
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• 2019

Objective: Terminalia arjuna plant, specially its leaves, bark, and roots, are widely used in traditional herbal medicine due to presence of bioactive components and being a rich source of natural antioxidants. But its fruit has not been used for any such purposes despite its potential to retard oxidation. Hence, the antioxidant potential of Arjuna fruit extract (AFE) in retarding lipid and protein oxidation of raw ground pork was evaluated during refrigerated storage for 9 days. Methods: The AFEs were prepared using different solvents viz. ethanol (EH), water, ethanol: water (60:40) and methanol:hot water (60:40). The AFEs were analysed for total phenolic content (TPC), 2, 2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power. Water extract (WE) and ethanol-water extract (EH-WE) were selected and incorporated at 1.0% into freshly minced pork meat and compared with a synthetic antioxidant, in retarding lipid and protein oxidation during storage. Results: The TPC in AFEs using different solvents ranged from 11.04 to 16.53 mg gallic acid equivalents/g and extracts exhibited appreciable scavenging activity ranging from 50.02% to 58.62%. Arjuna extracts significantly (p<0.05) improved the colour score of meat samples by reducing the formation of metmyoglobin during storage. Both the AFEs (WE and EH-WE) significantly (p<0.05) lowered the thiobarbituric acid reactive substances value, peroxide formation and formation of protein carbonyls in raw pork than control sample during storage. Upon sensory evaluation of all samples, it was found that AFE treatment could prolong the storage period of meat samples, without influencing the colour and odour score, up to 6 days. Conclusion: AFEs used at 1% improved the oxidative stability, colour and odour score and prolonged the refrigerated shelf life of ground pork up 6 days. Therefore, AFE could be explored as an alternative natural antioxidant in retarding lipid and protein oxidation in meat products.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.7
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• pp.1036-1043
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• 2019

Objective: To investigate the color and oxidative stabilities of longissimus lumborum (LL) and psoas major (PM) muscles from grain-finished Bos indicus cattle in Brazil. Methods: The LL and PM muscles were obtained 24 h post-mortem from eight (n = 8) Nellore bull carcasses, fabricated into 1.5-cm steaks, aerobically packaged, and stored at $4^{\circ}C$ for nine days. Steaks were analyzed for myoglobin concentration, pH, instrumental color, metmyoglobin reducing activity (MRA) and lipid oxidation. Results: The LL steaks exhibited greater (p<0.05) redness, color stability, and MRA than their PM counterparts on days 5 and 9. The LL and PM steaks demonstrated similar (p>0.05) lightness and yellowness on days 0, 5, and 9. On the other hand, PM steaks exhibited greater (p<0.05) myoglobin concentration, pH, and lipid oxidation than their LL counterparts. Conclusion: These results indicated that muscle source influenced the color and oxidative stabilities of beef from grain-finished Bos indicus animals. These results highlighted the necessity of muscle-specific strategies to improve the color stability of beef from grain-fed Bos indicus cattle.