Influence of CaCl2 and NaCl injections on the texture and flavour of beef

The present study compares the effects of pre− and post-rigor injections of 0.1 m CaCl₂ or 0.15 m NaCl on sensory characteristics (appearance, texture and flavour) and on physical measurements (sarcomere length, drip loss and mechanical resistance of raw myofibres) of beef meat at 2, 6 and 14 days of ageing. An injection of CaCl₂ 1 h post-mortem (pH ≈6.8) greatly decreased sarcomere length and myofibrillar resistance, increased drip loss, contracted appearance and brightness, and induced abnormal flavour, mainly bitterness, whatever the ageing time. CaCl₂-treatment 1 h post-mortem produced little effect on tenderness during ageing; it was slightly higher at day 2 and lower at day 14 than controls. CaCl₂-injection at 24 h post-mortem did not change the sarcomere length but produced a smaller increase in drip loss and a decrease in the resistance of raw myofibres. Improved meat tenderness compared to controls occurred mainly at days 2 and 6 but, during ageing, abnormal flavour appeared by day 6. NaCl-injection had no effect on either sarcomere length or resistance of raw myofibres, but produced higher drip loss and saltier taste at day 14 only. Thus pre-rigor injection of CaCl₂ is not recommended because of adverse effects on flavour and appearance of meat. Post-rigor injection of CaCl₂ has a beneficial effect on tenderness in the first part of the ageing period, but after complete ageing, the only overall benefit is a decrease in the variability between animals.     

Possible mechanism for the effect of the RN(-) allele on pork tenderness

The effect of the dominant RN⁻ allele on rigor development, ageing and tenderness was studied in M. longissimus dorsi (LD) from 11 heterozygous carriers and five non-carriers of the RN⁻ allele. Rigor development was followed by measurements of muscle shortening, isometric tension, pH and FOP. During ageing the myofibrillar length and Warner–Bratzler shear force were measured in the meat. Sensory analysis was performed at 4 days post-mortem using a trained expert panel. It was found that the decrease in pH was faster for RN⁻ carriers than non-carriers during the first 5 h post-mortem, after which the pH-time slope was similar for the two groups. This resulted in a significantly lower mean ultimate pH in LD from RN⁻ carriers than non-carriers. During rigor development the isometric tension was lower in RN⁻ carriers than in non-carriers, while contraction (shortening and sarcomere length) did not differ significantly between the two genotypes. The myofibrillar length, which is an indirect measure of the proteolytic activity that has occurred in the meat, was shorter for the RN⁻ carriers than for the non-carriers. The difference in myofibrillar lengths between the genotypes was significant at 1 and 4 days post-mortem but not at 7 days post-mortem, which indicates that the RN⁻ carriers have a higher proteolytic activity earlier post-mortem. The results from the Warner–Bratzler shear force measurements showed that the meat from the RN⁻ carriers was significantly more tender, 1 and 4 days post-mortem, than the meat from the non-carriers. The meat from non-carriers needed 7 days to reach the tenderness attained by that from the RN⁻ carriers 4 days post-mortem. The greater tenderness in LD from RN⁻ carriers than that from non-carriers was also confirmed by a sensory panel at 4 days post-mortem. In conclusion, differences observed in the course of rigor and ageing in muscle from carriers and non-carriers of the RN⁻ allele suggest that proteolytic action, as initiated by a more rapid fall in pH, is the most important factor governing the variation in tenderness of the two genotypes.     

Relationship between water mobility and distribution and sensory attributes in pork slaughtered at an age between 90 and 180 days

Water mobility and distribution were measured in M. longissimus dorsi from 41 pigs slaughtered at an age of 90, 140, 161 or 182 days using low-field proton NMR relaxometry, and in order to investigate the impact on sensory attributes, a sensory evaluation of the pork was performed in parallel. The sensory evaluation demonstrated a significant effect of slaughter age on juiciness of the meat, and a final juiciness score of 8.4, 7.7, 7.2 and 7.8 was obtained for meat from 90, 140, 161 and 182-day old pigs, respectively. The NMR measurements revealed that the higher juiciness in meat slaughtered at an age of 90 days could be ascribed to a longer relaxation time of the extramyofibrillar water, corresponding to more mobile water, in the fresh meat of 90-day old pigs compared with the older pigs. In the cooked meat the higher juiciness of meat from 90-day old animals could be ascribed to a more homogenous distribution of the myofibrillar water compared with meat from older pigs. In contrast, the NMR measurements showed no effects that could explain the higher juiciness in meat from pigs slaughtered at an age of 182 days compared with meat from pigs slaughtered at an age of 140 or 161 days. Possibly the increase in juiciness when the age at slaughter is increased from 161 to 182 days should be ascribed to an increase in intramuscular fat content, which was not evident in the NMR measurements.     

Effects of transport time and rest period on the quality of electrically stimulated male cattle carcasses

Ground, pre-salted, pre-rigor semimembranosus muscles of beef were subjected to three treatments A=rapid carbon dioxide (CO(2)) chilling, B=slow CO(2) chilling and C=air chilling, and compared to a control D=slow air chilling of muscles, which were subsequently ground and salted post-rigor. Meat of the pre-rigor treatments A, B and C had higher pH values during processing, lower cooking loss, firmer texture and a lighter yellowish external colour of cooked patties than the post-rigor control D (p<0.05). The two CO(2) chilling regimes A and B had no detrimental effects on the functional properties of the pre-rigor meat. Sarcomere lengths did not differ in meat of the four treatments (p>0.05), indicating that early pre-salting protected the meat from cold shortening during rapid temperature decline. A process combination of grinding, followed by immediate pre-salting and CO(2) chilling within 312h post-mortem of non-stimulated beef muscles is likely to yield superior binding properties of cooked patties and similar ground beef products.     

Tenderness of pre- and post rigor lamb longissimus muscle

Lamb longissimus muscle (n=6) sections were cooked at different times post mortem (prerigor, at rigor, 1dayp.m., and 7 days p.m.) using two cooking methods. Using a boiling waterbath, samples were either cooked to a core temperature of 70 °C or boiled for 3h. The latter method was meant to reflect the traditional cooking method employed in countries where preparation of prerigor meat is practiced. The time postmortem at which the meat was prepared had a large effect on the tenderness (shear force) of the meat (P<0.01). Cooking prerigor and at rigor meat to 70 °C resulted in higher shear force values than their post rigor counterparts at 1 and 7 days p.m. (9.4 and 9.6 vs. 7.2 and 3.7 kg, respectively). The differences in tenderness between the treatment groups could be largely explained by a difference in contraction status of the meat after cooking and the effect of ageing on tenderness. Cooking pre and at rigor meat resulted in severe muscle contraction as evidenced by the differences in sarcomere length of the cooked samples. Mean sarcomere lengths in the pre and at rigor samples ranged from 1.05 to 1.20 μm. The mean sarcomere length in the post rigor samples was 1.44 μm. Cooking for 3 h at 100 °C did improve the tenderness of pre and at rigor prepared meat as compared to cooking to 70 °C, but not to the extent that ageing did. It is concluded that additional intervention methods are needed to improve the tenderness of prerigor cooked meat.     

Effect of salt on oxidative changes in pre- and post-rigor ground beef

Pre- and post-rigor beef was ground and salt was added to give 0·0, 0·5, 2·0 and 4·0% NaCl (w/w). Samples were removed after 0, 24, 48, 72 and 96 h at 4°C and analyzed for pH, TBA numbers and percentages of reduced myoglobin (Mb), metmyoglobin (MMb) and oxymyoglobin (MbO(2)). After holding for 96 h the samples were cooked in a boiling water bath to an internal temperature of 80°C and held at 4°C for 48 h before TBA analysis. Pre-rigor grinding and salting reduced the post-mortem pH decline and the extent of meat discoloration as shown by the differences in the amount of MMb. The extent of lipid oxidation as measured by TBA numbers was not significantly different for the pre- and post-rigor ground salted meat samples, although salt accelerated oxidation during storage. Results demonstrated that pre-rigor grinding and salting of beef produces a more stable bright red color, which appears to be associated with a lower percentage of MMb and a higher ultimate pH in the pre-rigor salted meat.     

Effect of cooking temperature and time on the physico-chemical, histological and sensory properties of female carabeef (buffalo) meat

The effect of cooking temperature (80-100°C) and time (30-60min) on collagen solubility of Semimembranosus muscle in carabeef were investigated. The pH, cooking loss, shear force value, collagen content, collagen solubility, sensory evaluation and histological observations of water bath cooked and pressure cooked Semimembranosus meat samples were measured. Increase in pH, cooking loss, collagen solubility and tenderness scores with decrease in shear force value and collagen content was observed with increases in cooking temperature and time. However, no statistical difference was observed for shear force values, collagen solubility values and tenderness scores in pressure cooked meat and meat cooked in a water bath at 100°C for 45min, inferring that cooking of buffalo meat at 100°C for 45min improved collagen solubility and tenderness to the same extent as that due to pressure cooking.     

Relationship between collagen characteristics,lipid content and raw and cooked texture of meat from young bulls of fifteen European breeds

Variations in texture were determined for 10 day aged raw and cooked Longissimus thoracis (LT) muscle from 436 bulls of 15 European cattle breeds slaughtered at an age of 13–16 months. Variations in texture were related to differences in pH 24 h post-mortem, sarcomere length, collagen characteristics and lipid content. The shear force of cooked meat samples varied from 43.8 to 67.4 N/cm². Simmental, Highland and Marchigiana cattle had the highest shear force values and Avileña-Negra Ibérica, Charolais, Casina and Pirenaica cattle had the lowest values. Cooked meat toughness showed a weak negative correlation to lipid content (P < 0.001) but no correlation to collagen characteristics. Raw meat texture measured by compression correlated positively (P < 0.001) with total and insoluble collagen. In conclusion, collagen characteristics showed correlation to raw meat texture but not to cooked meat toughness of LT muscle in European young bulls.     

Performance, muscle composition and meat texture in veal calves administered a β-agonist (clenbuterol)

The effect of clenbuterol administration on performance, muscle composition and meat texture was studied in veal calves. Three groups, of ten animals each, were assigned to the three following treatments for 27 days: control, administration of 0·3 and 1·0 ppm in the feed (dry matter basis). After a 14-day withdrawal period, the animals were slaughtered, and three muscles were sampled (M. longissumus thoracis; M. triceps brachii caput longum; M. rectus abdominis). During the period of clenbuterol administration, the treated calves exhibited a higher daily liveweight gain (DLWG) and a higher feed conversion efficiency (FCE) compared to those of the control calves, but these effects were reversed during the subsequent withdrawal period. At slaughter, the overall DLWG, FCE and carcass weight were similar in the three treatments, but the dressing percentage in the clenbuterol-treated calves was up to 5·7 points higher than that of the control calves. In the muscles studied, the clenbuterol had little effect on pH, sarcomere length, dry matter and nitrogen contents, collagen heat stability (solubility, isometric tension) or cooking loss; but it markedly reduced the content of lipids, collagen and haem pigments. The clenbuterol also affected myofibrillar strength after ageing, measured either on raw meat or on cooked meat. This was particularly evident in cooked meat which showed up to a two-fold increase in mechanical parameters (maximum stress, compression modulus) after the clenbuterol treatment. No dose effect was detected except for the mechanical parameters. It was concluded that clenbuterol administration affects, meat in two opposite ways, viz. a marked toughening effects, due to a reduction in the muscle ageing rate, that is not compensated by a concomitant tenderizing effect (through a decrease in the intramuscular collagen content).     

Changes in lysosomal enzyme activities and shear values of high pressure treated meat during ageing

The effects of pressure treatment (520 MPa for 260 s at 10°C) on lysosomal enzyme activities, Warner-Bratzler (WB) shear values and physico-chemical parameters of post-rigor (day 2) beef (Biceps femoris and Longissimus dorsi muscles) were investigated immediately after treatment and during ageing. Activities of cathepsin D and acid phosphatase in pressurised meat samples were higher than in controls at 2 days post-mortem and throughout storage. This increase in activities was related to the breakdown of the lysosomal membrane and/or to enzyme activation. The WB peak forces were higher for pressurised samples of both muscles at 2 days than in the control and remained higher throughout ageing. The WB shear force deformation curves from pressurised samples showed that the increase in toughness was due to the increase in shear force of the myofibrillar component and not the collagen component. Pressurised muscle led to a significant decrease in sarcomere length and higher cooking loss. Post-rigor application of high pressure induced higher catheptic activity but no conclusive effect on the post-mortem rate of tenderization or tenderness of meat was observed.     

Inhibition of protease activity. Part 1. The effect on tenderness and indicators of proteolysis in ovine muscle

To examine the effect of particular enzyme groups on tenderness specific cysteine protease inhibitors were injected into muscle early post-mortem. The protease enzyme inhibitor E-64 was injected into the m. longissimus thoracis et lumborum (LTL) on the right side of 12 lamb carcasses within 15 min of death and in another 12 carcasses with the protease inhibitor Z-Phe-Ala-CHN(2). The left LTL (control) was injected with saline (0.25 M NaCl). To create variation in the rate of pH decline alternate carcasses were electrically stimulated (low voltage). The LTL was divided into cranial and caudal portions and aged for 1 or 2 days. Muscle samples at 1 day post-mortem were used for measurement of osmolality and sarcomere length (n=48), and others at 1 and 2 days post-mortem for shear force determination (n=96). The myofibrillar fragmentation index (MFI) was determined on samples taken at pH 6.2 and 1 and 2 days post-mortem (n=144). Other muscle samples were obtained at death, pH 6.2 and 6.0 and then at 1 and 2 days post-mortem (n=215). These samples were used for determination of protein solubility and the concentration of free amino acids. Stimulation caused a faster (P<0.05) decline in pH. There was no effect of stimulation (P>0.05) on shear force values, but injection of inhibitor and ageing both had effects (P<0.001). The inhibitor E-64 prevented any improvement in tenderness with ageing, whereas the inhibitor Z-Phe-Ala-CHN(2) and the control samples showed a similar ageing response. In the latter two treatments there was an average reduction of 1 kg in shear between 1 and 2 days post-mortem, whilst the inhibitor E-64 maintained shear force on average 2 kg higher than control samples. Injection and ageing had an effect on MFI (P<0.001) and there was an interaction (P<0.05) between stimulation and ageing for MFI, such that as stimulated muscle aged the rate of change of MFI was greater. There was an interaction between injection and ageing (P<0.05) for protein solubility such that samples treated with E-64 showed a minimal increase in protein solubility with ageing, whereas in samples treated with Z-Phe-Ala-CHN(2) and the control samples there was a significant increase. There was also an interaction between stimulation and ageing such that between sampling at pH 6.0 and 2 days post-mortem, stimulated muscle exhibited greater solubility (P<0.05). There were no effects (P>0.05) on the concentration of free amino acids. The evidence indicated that the cysteine proteases were responsible for post-mortem proteolysis and tenderisation, in particular the calpains, whereas the cathepsins (B and L) were unlikely to contribute to proteolysis and subsequent tenderisation in meat.     

Water characteristics in cooked beef as influenced by ageing and high-pressure treatment-an NMR micro imaging study

The water characteristics in cooked pressure-heat treated (45?°C for 45 min prior to pressurisation at 150 MPa for 30 min) and non-pressurised, cooked (control) samples of beef Longissimus aged for 1, 3, 8 or 16 days were studied by nuclear magnetic resonance microscopy. A multi-echo sequence was used to obtain T2 images, and independent of ageing period, the T2 values were found to be lower in pressure-heat treated meat revealing alterations in water characteristics of pressure-treated, cooked meat compared with cooked meat. With increasing ageing duration, the T2 values in both pressure-treated, cooked and cooked meat decreased indicating that the water became more tightly trapped in the protein network. In addition, independent of length of ageing period the relationship between cooking loss in the cooked meat and transverse relaxation differed between non-pressurised and pressure-treated meat, which reveals that the mechanisms changing the water properties in beef during ageing are different from those occuring during pressure-heat treatment of meat.     

Effects of high-intensity high-frequency ultrasound on ageing rate, ultrastructure and some physico-chemical properties of beef

High-intensity and high-frequency ultrasound was tested for its ability to accelerate meat ageing and increase beef tenderness. Samples (≈50g) of semimembranosus muscles from 8 cull cows were assigned to ultrasonic treatment (2.6MHz; 10W/cm(2); 2 ×15s) either pre-rigor (day 0, pH 6.2) or post-rigor (day 1, pH 5.4). When applied pre-rigor, ultrasound induced a slight delay in rigor mortis onset, a stretching (12-15%) of the sarcomeres (p<0.05), an ultrastructural alteration in the Z-line region and an immediate increase (around 30%) in the release of calcium in the cytosol (p<0.05). However, no conclusive effect on meat ageing rate was observed. Post-rigor ultrasonic treatment did not induce any structural modification but slightly improved the ageing index after 6 days (p<0.05). However, no improvement in the final (day 14) ageing index was observed compared to the controls. As ultrasound had also no effect on the thermal stability of collagen, at both postmortem times, no improvement in meat tenderness can be expected under the conditions used.     

Effects of stress and high voltage electrical stimulation on tenderness of lamb m. longissimus

This study was conducted to investigate the reported effect of pre-slaughter stress on meat tenderness independent from its effect on ultimate pH, and its interaction with electrical stimulation. From a group of 80 Coopworth lamb, 40 were stressed by subjecting the animals to a swim wash 3 h before slaughter and the use of dogs to assemble the animals to the access ramp of the abbatoir. Half of the carcasses of each group was electrically stimulated within 30 min post mortem. Temperature and pH decline of the longissimus was monitored and shear force of the cooked muscle was determined at 2 days post mortem and after 6 weeks vacuum storage at 1°C. To investigate an effect of stress independent of ultimate pH, 10 muscles with an ultimate pH below 5.8 were selected from each group for detailed analysis. This analysis consisted of determination of calpastatin activity and sarcomere length, and immunoblotting of μ-calpain and calpain substrates. The stress treatment led to an increase in the number of muscles with an ultimate pH above 5.8 (32.5 vs 15%), and muscles with an ultimate pH above 5.8 were significantly tougher than muscles with an ultimate pH below 5.8 at 2 days post mortem. Electrical stimulation improved tenderness at two days post mortem. This effect could be attributed to an effect on muscle contraction, but not on post mortem proteolysis of calpain substrates. A large variation in tenderness at 2 days post mortem was observed and this was not reduced by electrical stimulation. Six weeks of vacuum storage resulted in a 6 kgF drop in mean shear force and a uniformly tender product. Despite the fact that the stress treatment was similar to those in earlier studies, we failed to observe an effect of stress independent of ultimate pH on tenderness. The reason for this is unclear, but differences in the response to stress between breeds may be responsible. The results of the present study underscore the importance of minimizing pre-slaughter stress and adequate post mortem storage for meat quality.     

Manipulation of the pre-rigor phase to investigate the significance of proteolysis and sarcomere length in determining the tenderness of bovine M. longissimus dorsi

The objective of this study was to evaluate the importance of proteolysis and sarcomere length in determining the tenderness of bovine M. longissimus dorsi (LD) muscle over a 21-day period. This was done by altering the pre-rigor glycolytic behaviour of hot-boned LD muscles using different early post-mortem temperature regimes. Hot-boned LD muscles (n=8) were cut in two, randomised, placed in polythene bags and submerged in a water bath set at 5°C (rapidly chilled) and 15°C (slowly chilled) for 8h post-mortem. All muscles were then stored at 2°C for up to 21 days post-mortem. The temperature regimes altered the glycolytic behaviour of the muscles in the pre-rigor period. The slowly chilled muscles exhibited a faster (P<0.01) pH fall than rapidly chilled muscles. Cold shortening was induced in rapidly chilled muscles as they had shorter (P<0.01) sarcomere lengths than slowly chilled muscles up to day 21 post-mortem. Warner Bratzler shear force values (WBSF) deemed cold-shortened muscles as tougher than noncold shortened up to day 14 post-mortem. Both cold-shortened and noncold-shortened muscles tenderised over time to an extent where there was no significant difference in WBSF values by day 21 post-mortem. SDS-PAGE protein profiles indicated that the rate of proteolysis was faster in slowly chilled muscles when compared to rapidly chilled muscles. However by day 21 post-mortem it appeared that rapidly and slowly chilled muscles underwent proteolysis to the same extent.     

Effect of post-slaughter processing and freezing on the functionality of hot-boned meat from young bull

The effects of variation in the times of mincing post mortem (2, 4, or 6 h), pre-rigor salting (1.5% wt wt ) and freezing rate [fast (10 min, liquid nitrogen); medium (4-6 h at -40 °C and 0.8 m s(-1) air velocity); or slow (36-38 h at -10 °C and 0.1 m s(-1) air velocity followed by 12 h at -20 °C and 0.1 m s(-1) air velocity)] on the functionality of young bull meat were examined using hot-boned forequarters. At 52 h post packaging, the meat was thawed (72 h at 4 °C), its pH measured, and it was used to make finely comminuted batters. Cook yield and stress and strain of the cooked batters were measured. Time of mincing had no effect on meat pH, cook yield or stress and strain. There was a significant interaction (P < 0.05) between pre-rigor salting and freezing rate for pH. Freezing rate did not affect the pH of pre-rigor salted meat whereas the pH of unsalted pre-rigor meat was highest at the fastest freezing rate. Meat salted pre-rigor had a significantly (P < 0.05) higher pH than the post-rigor chilled control. Pre-rigor salting decreased the stress values of cooked batter whereas the slowest freezing rate increased stress. Stress and strain values for cooked batters from thawed meat were not significantly different from the values for batters made from the unfrozen control. Cook yields of batters made from pre-rigor frozen meat were higher than that of the postrigor control but not significantly so. The results indicate that suppliers can use pre-rigor salted and frozen meat when manufacturing comminuted products without major detrimental effects on the cook yield and texture of the finished product.     

Preserving pre-rigor meat functionality for beef patty production

Three methods were examined for preserving pre-rigor meat functionality in beef patties. Hot-boned semimembranosus muscles were processed as follows: (1) pre-rigor ground, salted, patties immediately cooked; (2) pre-rigor ground, salted and stored overnight; (3) pre-rigor injected with brine; and (4) post-rigor ground and salted. Raw patties contained 60% lean beef, 19.7% beef fat trim, 1.7% NaCl, 3.6% starch, and 15% water. Pre-rigor processing occurred at 3-3.5h postmortem. Patties made from pre-rigor ground meat had higher pH values; greater protein solubility; firmer, more cohesive, and chewier texture; and substantially lower cooking losses than the other treatments. Addition of salt was sufficient to reduce the rate and extent of glycolysis. Brine injection of intact pre-rigor muscles resulted in some preservation of the functional properties but not as pronounced as with salt addition to pre-rigor ground meat.     

Genetic and environmental effects on meat quality

In order for livestock industries to consistently produce high quality meat, there must be an understanding of the factors that cause quality to vary, as well as the contribution of genetics. A brief overview of meat tenderness is presented to understand how genotype and environment may interact to influence this trait. Essentially, meat tenderness is determined from the contribution of connective tissue, sarcomere length determined pre-rigor and rate of proteolysis during ageing, as well as contributions from intramuscular fat and post-mortem energy metabolism. The influence of mutations in myostatin, the callipyge gene, the Carwell or rib eye muscle gene as well as the calpain system on meat tenderness is presented. Specific examples of interactions between the production or processing environment and genetics are presented for both sheep and cattle. The day-to-day variation in tenderness is evident across experiments and this variation needs to be controlled in order to consistently produce tender meat.     

Ion distribution and protein proteolysis affect water holding capacity of Longissimus thoracis et lumborum in meat of lamb subjected to antemortem exercise

Exercise has been shown previously to reduce the water holding capacity (WHC) of meat in lamb. The consequence of changes in the distribution of ions pre- and post-rigor and proteolysis on WHC is relatively unknown. Twelve crossbred lambs were used to investigate the effect of exercise on the meat quality traits of the Longissimus thoracis et lumborum (LTL) muscle. There were no treatment effects on Warner-Bratzler shear force (WBSF), myofibril and sarcoplasmic protein solubility, denaturation or sarcomere length. With exercise the initial pH of the muscle was lower and the rate of pH fall to rigor was faster compared to controls. Exercise caused increased purge and meat fluid had a lower osmolarity, magnesium, potassium and sodium concentration. Proteolysis of desmin occurred after day 3 and vinculin on day 7 of ageing with exercise. It was concluded that exercise caused changes in the distribution of ions and the proteolysis of muscle proteins that reduced the ability of the muscle to bind or hold water.     

Effect of modified atmosphere packaging on structural and physical changes in buffalo meat

The effect of modified atmosphere packaging of buffalo meat on the structural parameters viz., fibre diameter, sarcomere length and myofibrillar fragmentation index and physical parameters viz., pH, drip loss and colour scores were studied. The buffalo meat was packed under aerobic, vacuum and modified atmosphere (80% oxygen+20% carbon dioxide) and stored at 4±1°C upto 21 days. The results obtained revealed that vacuum-packed buffalo meat had the lowest fibre diameter and myofibrillar fragmentation index and the highest sarcomere length, vacuum thus appears to enhance ageing. Buffalo meat packed in modified atmosphere had a low drip loss and a desirable colour. The modified atmosphere packed and vacuum-packed buffalo meat was acceptable for upto 14 days at 4±1°C.