• Applied Biological Chemistry
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• v.14 no.2
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• pp.165-169
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• 1971

From both breast and leg muscle of 12 week-old broiler chicken held for aging in slushed ice and dry chilling at $33-35^{\circ}F$., myosin, actomyosin and other nitrogenous fractions were extracted with KCl-phosphate buffer for various periods from 1 hr. to 25 hr. post-mortem. The changes in extractable nitrogen occurred mainly as a result of decrease in extractability of myosin and to some extent, increase in extractability of actomyosin. Changes in stroma, sarcoplasmic and NPN fractions were small. Myosin extractability decreased rapidly during the first 3 hr. post-mortem and then reduced Continuously in both leg muscle and breast muscle during wet chilling. The decrease of myosin extractability in leg muscle was much more than that in breast muscle, and then the extractability increased after 17 hr. post-mortem in dry chilling. Actomyosin was extracted at low consistent level in wet chilling, while it increased considerably after 17 hr. post-mortem in dry chilling. The tendency was similar in both breast and leg muscle.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.2
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• pp.279-282
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• 2002

Twenty six male Hanwoo (Korean cattle) carcasses were measured for pH, temperature and instrumental color changes of loins during 24 h post-mortem carcass chilling at $4^{\circ}C$ in the cooler. The average internal temperature of loins was about $5^{\circ}C$ after 24 h of chilling, and with the exclusion of those with an ultimate pH>6.0 (dark-cutters), the average pH value was 5.5. When all carcasses were considered for the partial correlation coefficient between color and pH, with the temperature effect excluded, CIE $L^*$, $a^*$ and $b^*$ seemed to be affected significantly by pH during chilling process (p<0.001). However, when carcasses with dark-cutting condition were excluded, the correlation coefficients were much lower. In contrast, when the partial correlation coefficients between color and temperature, excluding the effect of pH on them, were analyzed, the relationship between color and temperature did not change much after values of DFD (dark, firm, dry) beef were excluded. The results suggested that the known interrelationship of color and pH in chilled beef loins be mainly due to the influence of temperature on pH and color.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1895-1900
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• 2007

An experiment was carried out to investigate the effects of different chilling temperature on duck breast and leg meat quality. Duck carcasses were chilled for 30 minutes in water at either $0^{\circ}C$, $10^{\circ}C$ or $20^{\circ}C$ within 20 minutes of post mortem with 6 carcasses per group. Results showed no significant effects of chilling temperature on ultimate pH, protein solubility, sarcomere length and shear force value for duck breast or leg meat (p>0.05). Leg meat had higher ultimate pH, redness and shear force value, lower cooking loss, lightness, yellowness and protein solubility values than breast meat. The interaction of meat type and chilling temperature on cooking loss was significant (p<0.05). The effect of chilling temperature on cooking loss was more severe in leg meat than breast meat and $20^{\circ}C$ chilling resulted in significantly higher cooking losses than the other chilling temperatures. Results of this experiment revealed that duck carcass can be chilled at $10^{\circ}C$ without any harmful effect on meat quality including toughness of meat.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2002.05a
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• pp.17-25
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• 2002

Application of electrical stimulation in the red meat species (eg. beef and sheep) processing has been erratic around the world and this may reflect an incomplete knowledge of how to optimise the technology. Although it is well established that stimulation increases the rate of post-mortem glycolysis other biochemical and biophysical effects have been implicated with the use of this technology. On the basis of currently available knowledge, this mini-review seeks to examine the current theories about the effect of stimulation on post-mortem muscle. The classical view that stimulation prevents muscle from shortening excessively during rigor development has been expanded to include the possibility that it also results in physical disruption of muscle structure. The interaction of these effects with the acceleration of the rate of proteolysis through activation of the calpain protease system has not been comprehensively reviewed in the past. As a result of conclusion driven, this article highlights several areas that may prove fruitful for further research. The challenge for further development of electrical stimulation systems is optimisation of the activation of the enzyme systems in parallel with manipulation of chilling regimes so as to ensure rigor mortis is achieved at temperatures which minimise shortening. The potential of regional stimulation of sections of the carcass to achieve this outcome is worthy of study given the different fibre composition of muscles and temperature gradients.

• 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 $30^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.5
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• pp.738-744
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• 2008

In most developing countries consumers purchase retail cuts from hot carcasses and prepare traditional meat products as per their convenience and requirements. In this study, effects of different post mortem handling practices on quality of meat curry from culled sheep meat have been studied. After slaughter, leg cuts were subjected to nine commonly prevalent handling conditions in India viz. deboning (boning out) and cooking within 2-3 h (1), deboning immediately and cooking after 5-6 h (2), deboning after 5-6 h and cooking (3), deboning immediately, storage at $4^{\circ}C$ for 24 h and cooking (4), chilling for 24 h at $4^{\circ}C$, deboning and cooking (5), deboning after 5-6 h, storage for 24 h at $4^{\circ}C$, and cooking (6), deboning after 5-6 h, storage for 48 h at 4??C and cooking (7), deboning after 5-6 h, freezing and cooking (8), deboning after 5-6 h, storage for 24 h at $4^{\circ}C$, freezing and cooking (9). Significant differences were observed in pH, water-holding capacity, cooking loss and shear force values. Sensory scores were significantly higher in conditions (1), (5) and (9), and significantly lower in conditions (4) and (6). From the results, it was concluded that, to have the best quality product, meat should be cooked either immediately after slaughter or should be deboned just before cooking. Storage of deboned meat at refrigerated temperature must be avoided.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.6
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• pp.898-904
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• 2006

Effects of sodium bicarbonate (SBC) injection on meat quality and functionality of porcine M. longissimus lumborum were investigated. Fifteen pigs ($100{\pm}5kg$) were randomly selected at a commercial slaughter plant. After slaughtering the loins were dissected from the carcass before chilling at approximately 30 minutes post mortem. The loins were divided into four cuts for sample treatment, and SBC of 0.25 M, 0.40 M and 0.75 M was injected (2% w/w) using a syringe. As SBC injection level was increased, muscle pH increased significantly (p<0.05). SBC injection decreased lightness ($L^*$) values on the surface of muscle. Moreover, with injection of SBC, drip loss %, cooking loss % and shear force were significantly (p<0.05) decreased, whereas WHC and $Na^+$ content were significantly (p<0.05) increased. From panel testing of uncooked pork loin, no significant differences (p>0.05) were found in aroma, off-flavor and drip between injection of SBC at different levels and the control, although color and acceptability were significantly lower (p<0.05) in control pork loin compare with injection of SBC at 0.75 M. In cooked pork loin from the panel test, aroma, flavour, off-flavour and juiciness were found to be similar (p>0.05) on all treatments, but tenderness and acceptability were significantly higher (p<0.05) with injection of SBC at 0.75 M than for control loin. Myofibrillar protein solubility of muscles treated with SBC was significantly (p<0.05) higher than that of the control, although no significant differences (p>0.05) were found in sarcoplasmic protein solubility between the treatments. These results indicated that SBC injection into pre-rigor porcine M. longissimus lumborum could improve ultimate pork quality characteristics such as meat color, water-holding capacity, and could inhibit muscle protein denaturation due to an increase in muscle pH.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.2
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• pp.246-253
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• 2017

Objective: Present study explores the effect of hot summer period on the glycolytic rate of early post-mortem meat quality of Ghungroo and Large White Yorkshire (LWY) pig and comparative adaptability to high temperature between above breeds by shifting the expression of stress related genes like mono-carboxylate transporters (MCTs) and heat shock proteins (HSPs). Methods: Healthy pigs of two different breeds, viz., LYW and Ghungroo (20 from each) were maintained during hot summer period (May to June) with a mean temperature of about $38^{\circ}C$. The pigs were slaughtered and meat samples from the longissimus dorsi (LD) muscles were analyzed for pH, glycogen and lactate content and mRNA expression. Following 24 h of chilling, LD muscle was also taken from the carcasses to evaluate protein solubility and different meat quality measurements. Results: LWY exhibited significantly (p<0.01) higher plasma cortisol and lactate dehydrogenase concentration than Ghungroo indicating their higher sensitivity to high temperature. LD muscle from LWY pigs revealed lower initial and ultimate pH values and higher drip loss compared to Ghungroo, indicating a faster rate of pH fall. LD muscle of Ghungroo had significantly lower lactate content at 45 min postmortem indicating normal postmortem glycolysis and much slower glycolytic rate at early postmortem. LD muscle of LWY showed rapid postmortem glycolysis, higher drip loss and higher degrees of protein denaturation. Ghungroo exhibited slightly better water holding capacity, lower cooking loss and higher protein solubility. All HSPs (HSP27, HSP70, and HSP90) and MCTs (MCT1, MCT2, and MCT4) in the LD muscle of pigs inclined to increase more in Ghungroo than LWY when exposed to high temperature. Conclusion: Effect of high temperature on the variation of HSPs and MCTs may play a crucial role in thermal tolerance and adaptation to different climatic conditions, pH regulation, muscle acidification, drip loss, protein denaturation and also in postmortem meat quality development.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.415-422
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• 2005

The pork loin used in this study was obtained from carcass chilled for 24 hours after slaughter and divided into 2 pare. The first part was air packaged and the other part was vacuum packaged, both of which were chilled at $4^{\circ}C$. After 2 days of slaughter, the qualities of air packaged loin chilled for 1 day showed lower drip lose, higher water holding capacity and better sensory texture than the vacuum packaged port (p<0.05). On the other hand, the air packaged loin chilled for 2 days showed lower drip loss and shear force value(SFV), higher Hunter's $a^*$ value, higher amount of taurine and alanine, and better taste, texture, juiciness and palatability than the vacuum packaged pork (p<0.05). However, the air packaged loin chilled for 3 days showed lower hip loss, chewiness SFV, higher amount of VBN $(12.37\;mg\%)$ and total plate count $(2.6\times10^4\;CFU/cm^2)$ than the vacuum packaged pork chilled for the same day (p<0.05). for the same chilling period, there was not significant difference between air and vacuum packaged pork in pH, TBA value, $L^*$ value, $b^*$ value, cooking loss, hardness, springness, cohesiveness, gumminess, total free amino acid contents and cooked meat aroma (p>0.05). Considering all these results, it is recommended that the way of air packaging for the pork with a short storing period should be reconsidered to cut down expenses.