Muscle Ultimate pH Research Articles

The influence of season on quality characteristics of hot-boned beef m. longissimus thoracis

Samples of m. longissimus thoracis (LT) muscle were randomly collected from 70 Omani beef cattle 1 h after slaughter between August 2001 and July 2002 in the Muscat Municipality central slaughterhouse to investigate the effect of seasonal parameters on meat quality during the hot and cool seasons of Oman. The collection period (12 months) was divided into two seasons according to ambient temperatures and relative humidity and termed: Cool Season (November–March with average temperature of 21.2±1.40 °C and 57.9±1.61% relative humidity) and Hot Season (April–October with average temperature of 34.3±1.67 °C and 48.8±7.57% relative humidity). The season had a significant effect on meat quality characteristics of the LT muscle. Muscles collected during the hot season had significantly ( P<0.001) higher ultimate pH values (6.24) with significantly ( P<0.001) lower Warner–Bratzler (WB) shear force values (10.12) than those collected during the cool season (5.54 and 15.58). In these hot-boned samples, there was a linear relationship between ultimate pH and WB shear values. Cooking loss was significantly ( P<0.001) higher for cool season samples (26.01%) than from hot season samples (19.75%). Beef from the hot season group had significantly ( P<0.001) darker meat than that of the cold season group, based on L* (31.45 vs 35.58), a* (18.53 vs 23.19) and b* (4.16 vs 6.40) colour measurements. There was a linear relationship between ultimate pH and cooking loss, L*, a* and b*. These results indicated that heat stress (>30 °C) lead to physiological stress in beef cattle, which in turn increased muscle ultimate pH and influenced related meat quality characteristics.

Derivation of the probability density function for ultimate muscle pH in slaughtered animals

AbstractWe consider the form of the probability density function for the ultimate muscle pH in slaughtered animals. Muscle pH in slaughtered animals is dependent on a biochemical process which forms lactic acid from the breakdown of glycogen stored in the muscle at slaughter. The relationship between glycogen and muscle pH after slaughter is expressed as a pair of coupled differential equations. The solution of this system for the equilibrium muscle pH as time → ∞ gives the form of the probability density for the ultimate muscle pH. When the initial density for the muscle glycogen is normal, the density for the ultimate muscle pH is shown to be approximately a mixed normal density.

The effect of feeding ractopamine (Paylean) on muscle quality and sensory characteristics in three diverse genetic lines of swine.

The present experiment utilized Berkshire (n = 76), Duroc (n = 81), and high-lean commercial crossbred (n = 75) barrows and gilts with an initial BW of approximately 85.1 kg. Pigs were fed a standard commercial diet (17.6% CP, 1.02% lysine) supplemented with ractopamine hydrochloride at a level of 0 or 10 ppm for 28 d. The experiment was conducted in a randomized complete block design, with animals blocked within genetic line according to litter, gender, and weight, for a total of four blocks per genetic line for each treatment. Pigs were harvested at a commercial abattoir and chilled for 24 h at 1 to 4 degrees C. At 24 h postmortem, wetness and firmness scores and ultimate muscle pH were measured in the center of the longissimus muscle (LM) at the 10th to 11th rib interface. Visual and instrumental color and marbling score were measured at 48 h postmortem on a fresh cut LM surface. Percentage of chemically extracted intramuscular fat (IMF) was measured, and a trained sensory panel evaluated cooked LM chops for juiciness, tenderness, and chewiness. Cooking loss (%) and instrumental measurement of tenderness also were measured on cooked LM chops. Ractopamine treatment increased ADG (P < 0.01) and LM area (P < 0.05), but had no effect (P > 0.05) on LM quality, sensory attributes, or instrumental measures of palatability. Berkshire LM received higher tenderness and juiciness (P < 0.05) scores and had lower cooking losses (P < 0.05) and instrumental tenderness (P < 0.05) than LM from the Duroc and high-lean lines. Loins from barrows were firmer (P < 0.05), had lower drip loss percentages (P < 0.05), and received greater tenderness scores (P < 0.05) than the LM from gilts. Genetic line x treatment and gender x treatment interactions were detected for IMF. The LM of Berkshire pigs fed ractopamine had lower (P < 0.05) IMF than Berkshires fed the control diet, with no interaction in the other lines. Purebred barrows (Berkshire and Duroc) had greater (P < 0.001 and P < 0.05, respectively) IMF than their respective purebred gilts, with no gender difference in IMF in the high-lean line. Results from the present study indicate that feeding ractopamine does not affect most muscle quality and palatability characteristics. However, the genetic line x treatment interaction for loin IMF suggests that feeding ractopamine might reduce IMF within the loin muscle of genetic lines that have a propensity to produce greater levels of IMF.

Sensory meat quality, ultimate pH values, blood parameters and carcass characteristics in reindeer (Rangifer tarandus tarandus L.) grazed on natural pastures or fed a commercial feed mixture

Sensory properties in meat, ultimate muscle pH values, blood metabolites and carcass characteristics from reindeer grazed on natural pasture (n=23) or fed a commercial feed mixture (n=17) were studied. Reindeer fed commercial feed generally had lower ultimate pH values (increased glycogen stores) in all three muscles measured (Mm. triceps brachii, longissimus and biceps femoris) compared with the animals grazing natural pasture. Raised plasma urea concentrations in all reindeer were explained by a relatively high intake of protein for both treatments. Aspartate aminotransferase (ASAT) activities in all animals were low, and did not indicate muscle degeneration due to stress. However, the measured plasma cortisol concentrations showed that all reindeer were affected by the immediate pre-slaughter handling. Sensory evaluation was performed both as a descriptive test using a selected and trained panel, and as a preference test carried out with two groups of consumers (experienced and non-experienced reindeer meat eaters). The trained panel concluded that meat from reindeer fed commercial feed scored higher for liver and sweet flavour intensities and lower for off-flavour compared with meat from reindeer grazing natural pasture. The consumer test showed no effect of consumer age, gender or residence on the preference for meat from reindeer on either feed. The importance for the reindeer industry to acknowledge and use the differences in flavour and consumer preference as a specialised marketing strategy for reindeer meat is discussed.

Effect of electrical stunning on meat and carcass quality in lambs

The effect on meat quality and the presence of haemorrhages were assessed in head-only electrically stunned and non-stunned lambs. Colour ( L∗, a∗, b∗), muscle ultimate pH (pHu), chilling losses and carcass weight at 45 min and 24 h were not significantly different between treatments. However, the amount of blood lost relative to live body weight and the killing-out were significantly higher ( P<0.05) in electrically stunned lambs compared with non-stunned lambs. No carcasses with petechiae, ecchymosis, haematomas and bone fractures were found in either treatment. On the other hand, the incidence of hearts with petechiae was significantly ( P<0.05) higher in electrically stunned lambs compared with lambs slaughtered without prior stunning. It is concluded that meat quality and the incidence of haemorrhages are unaffected by head-only electrical stunning for 3 s at a constant voltage of 250 V.

Myosin heavy chain isoforms account for variation in pork quality

The objective of this study was to determine the impact of myosin heavy chain (MyHC) isoforms (I, IIB, IIA and IIX) on pork quality traits of halothane (HAL)-negative (NN) and halothane-carrier (Nn) pigs. Gilts ( n=32) were assigned to a 2×2 factorial of genetic population (GP) and slaughter weight (WT; 120 and 135 kg). Classical meat quality characteristics were collected and MyHC content was determined on muscle samples. Regression equations for pork quality and carcass composition traits were determined. Only I/IIB accounted for variation in drip loss of NN gilts ( R 2=0.18), while GP related to drip loss in Nn gilts ( R 2=0.70). Type I MyHC content explained variation in ultimate (24 h) muscle pH of NN gilts ( R 2=0.09), while I/IIB, I/IIX and IIB/IIX were significant for Nn gilts ( R 2=0.99). I/IIA, I/IIX, IIB/IIX and GP accounted for variation in Hunter Color a (redness) values of NN gilts ( R 2=0.69), while IIB, IIA, IIB/IIA and GP were significant for Nn gilts ( R 2=0.97). Overall, fiber type composition accounts for a larger proportion of variation in the quality traits of Nn compared to NN gilts.

The effect of genotype, sex and management strategy on the eating quality of pork

Two hundred and sixteen (Large White×Landrace×Duroc) crossbred pigs were used to determine the influence of genotype, sex, and management strategies on pork quality. The experiment was a 2×3×3 factorial design with the main treatments being genotype (A — 50% and B — <25% Duroc bloodline), sex (females, surgical barrows and immunological barrows) and management strategy (control — C, dietary conjugated linoleic acid supplementation — CLA, and porcine somatotropin administration — pST). Genotype A pigs had less backfat (P2 site), higher intramuscular fat percentage, higher muscle ultimate pH (pH u) and surface exudate, and the pork was tougher and less acceptable compared with Genotype B pigs. Female pigs had lower muscle pH u, higher surface exudate and tougher pork compared with both surgical and immunological barrows. Pigs fed the control diet had lower muscle pH u and higher surface exudate compared with pigs fed the CLA supplemented diet or administered pST. Pigs fed the control diet had higher consumer likeness scores for flavour, tenderness, juiciness and overall acceptability compared with pigs fed the CLA supplemented diet or administered pST. The results from this experiment indicate that pork eating quality is reliant on a complex interaction between genotype and sex. The results also indicate that management strategies such as pST administration and CLA supplementation, while being effective in reducing backfat, have the potential to have a negative impact on pork quality.

Variation in the colour of broiler breast fillets in the UK

1. The normal range in colour of broiler breast muscle was assessed using an objective (instrumental) measure of colour in portioned breast fillets at a commercial processing plant. In addition, the relationship between colour and ultimate muscle pH (pH ult ) was also examined. 2. Considerable variation in colour was evident although minimal inter-flock variation was found. The exceptions were 2 free range flocks which produced breast fillets significantly lighter and less red. 3. Extremes of colour are likely to be discriminated against at the point of purchase. 4. A clear relationship between pH ult and L* values was found which provides more evidence for the existence of a PSE-like condition in broiler breast meat.

Characteristics of Pale, Soft, Exudative Broiler Breast Meat

The objective of the study was to characterize pale breast meat, compare it with normal colored breast meat, and determine whether it should be considered pale, soft, and exudative (PSE). Characteristics of 20 normal and 20 pale broiler breasts, obtained at a commercial slaughter plant, were evaluated. Compared with normal meat, the pale breast meat had a significantly (P < 0.05) lower pH (5.7 vs. 5.9), higher color L* value (60.0 vs. 55.1), higher drip loss (1.34 vs. 0.87%), lower marinade uptake (31.2 vs. 44.3%), and lower cooking yields (95.2 vs. 105.8%). Protein solubility in pale samples was slightly (P < 0.05) lower than in normal samples, which suggests increased protein denaturation in the pale breasts. Correlations between pH and L* value (r = −0.76), pH and marinade uptake (r = 0.64), sarcoplasmic protein solubility and L* value (r = −0.71), and sarcoplasmic protein solubility and moisture uptake (r = 0.66) and cooking yield (r = 0.66) were significant (P < 0.05). Correlations between total protein solubility and moisture uptake or cooking yields were not significant. The low ultimate pH of pale breast muscle appears to be the main determinant of its low water-holding capacity (WHC). This lower pH was unrelated to a higher lactate concentration or glycolytic potential of the pale muscle. Further research is needed to determine the causes of the low pH and possible measures to increase the pH (and functionality) of pale broiler breast muscle. Because the pale breast muscle has a low WHC, it can be considered PSE.

Effect of some electrical stimulation variables on wing flapping, post-mortem glycolysis and eating quality characteristics of broiler Pectoralis major muscle

1. The influence of different rates of wing flapping on the rate of post-mortem glycolysis in the Pectoralis major (PM) muscles of commercially-processed broilers was investigated. This was achieved by applying 300 pulses of low voltage electrical stimulation (ES) shortly after slaughter at various frequencies and pulse widths. The rate of post-mortem glycolysis was assessed by measuring muscle pH values at 20 min post mortem (pH 20 min ). 2. ES gave a mean pH 20 min value of 6.01, significantly lower than that of the control carcases which had a mean value of 6.45. Within ES treatments, variation in pulse frequency between 1/s and 10/s and in pulse width from 5 to 20 ms had no influence on pH 20 min values as measured by direct probe. However, differences between mean pH 20 min values attributable to pulse frequency were detected when measured by the iodoacetate method. 3. A further experiment was carried out to determine how different rates of wing flapping would affect the eating quality of PM muscles from commercially-processed broilers stored at chill temperatures for 24 h post mortem . This was achieved by using pulse frequencies of 1/s, 5/s and 10/s, all other ES variables being standardised. Pulse frequency had no effect on ultimate pH, sarcomere length, cooking loss or tenderness of PM muscle compared to controls. 4. We concluded that the rate of wing flapping post-slaughter has no effect, per se , on the extent of post-mortem glycolysis in broiler PM muscle or on its subsequent meat quality assessed after holding the carcases under chill storage conditions for 24 h.

Frequency of the Rendement Napole RN- allele in a population of American Hampshire pigs.

A total of 204 purebred Hampshire pigs were obtained from 23 breeders. These animals were the progeny of 41 sires and 123 dams. A sample of purebred Yorkshire (n = 24) pigs were also used in the study. Animals were classified by glycolytic potential determined on a live-animal longissimus muscle biopsy sample. Hampshire pigs (n = 176) with glycolytic potential greater than 185 micromol/g (x = 238.8 micromol/g; SD = 29.54) were classified as heterozygous or homozygous for the dominant RN- allele (RN-rn+ or RN-RN-, respectively), whereas cohorts (n = 28) with glycolytic potential less than 185 micromol/g (x = 141.3 micromol/g; SD = 24.48) were considered as homozygous normal (rn+rn+). All Yorkshire pigs (n = 24) had a mean glycolytic potential level of 146.1 micromol/g (SD = 20.18) and were considered as homozygous normal (rn+rn+). The Hardy-Weinberg equilibrium yielded frequencies of .630 and .370 for the dominant RN- allele and normal rn+ alleles in the Hampshire population, respectively, and genotypic frequencies of .397 (RN-RN-), .466 (RN-rn+), and .137 (rn+rn+). Hampshires with glycolytic potential > or = 185 micromol/g had significantly lower longissimus muscle ultimate pH, intramuscular fat, subjective marbling scores, and percentage of protein (P < .001) and had greater longissimus muscle percentage of moisture (P < .001), drip loss (P < .01), and cooking loss (P < .001) than rn+rn+ Hampshires and Yorkshires. These data suggest the RN- allele exists at a high frequency within the American Hampshire breed. Higher glycolytic potential levels, which accompany the allele, may cause decreased meat quality.

Composition, solubility and gel properties of salt soluble proteins from two bovine muscle types

The composition, pH solubility profile and thermal gelation behavior of two bovine muscles, vastus intermedius (VI, predominately red fibers) and semimembranosus (SM, predominantly white fibers) were compared. VI had a higher fat content and pH and lower protein content than SM. Between pH 5.2 and 5.8, the salt soluble proteins (SSP) from SM were more soluble than those from VI at the same pH, whereas solubilities above pH 6.0 were similar. Properties of SSP gels were measured at pH 5.5 and 6.1, the ultimate pH for SM and VI, respectively. Water lost from the VI gels due to syneresis was about 3 times greater than that lost from SM gels. VI gels prepared at pH 5.5 were firmer ( p<0.05) than at pH 6.1, whereas deformability of SM gels at pH 6.1 were greater ( p<0.05) than at pH 5.5. No differences ( p>0.05) were observed between the firmness or deformability of VI or SM gels when compared at the same pH. Results suggest that ultimate muscle pH and fiber type do influence the properties of bovine SSP gels, although the effect is not as great as that previously reported for poultry muscle proteins.

Glycogen metabolism and ultimate pH of muscle in Merino, first-cross, and second-cross wether lambs as affected by stress before slaughter

This experiment compared the metabolism of muscle glycogen and the ultimate pH (pHu) of muscle in Merino and crossbred lambs fed the same diet but subjected to different levels of stress pre-slaughter. Twenty- five Merino, 24 first-cross (Merino dam × Poll Dorset sire), and 23 second-cross (Border Leicester × Merino dam and Poll Dorset sire) wether lambs (6 months old, 30 kg liveweight) were maintained for 8 weeks on a complete pelleted diet based on lupin seed, straw, and barley grain (metabolisable energy, 10.8 MJ/kg; protein, 17.4% in dry matter), with a feed intake of 1.3 kg dry matter /day for each breed. At Week 6, muscle biopsies were taken from 15 lambs of each breed, and at Week 8, 5 animals from each breed were slaughtered at an experimental abattoir 10 min after removal from their pens (low pre-slaughter stress). The remaining lambs, separated into breeds, were transported for 2 h and slaughtered after 24 h lairage at a commercial abattoir. Muscle samples were taken at slaughter, and assayed with the biopsy samples for glycogen concentration (corrected for lactate concentration), myoglobin concentration, and citrate synthase activity. The pHu of muscle was measured 48 h post slaughter. Compared with commercially slaughtered lambs, the muscle tissues of lambs subjected to low pre-slaughter stress had higher glycogen concentrations post mortem, lower pHu, and no significant loss of glycogen between pen and slaughter. Breed had no effect on glycogen, pH, or the colour of muscle under low-stress slaughter conditions or when the muscle biopsy was taken. In contrast, breed had a significant influence under commercial slaughter conditions, the muscle of Merino lambs having the lowest glycogen concentration post portem, and the highest pHu and loss of glycogen between pen and slaughter. Irrespective of stress, second-cross lambs had higher myoglobin concentrations and citrate synthase activities than the Merino lambs, indicating greater pigmentation of muscle in the second-cross animals. We conclude that higher proportions of Merino genes are associated with a greater sensitivity to stress in lambs destined for slaughter.

Effect of mixing boars during lairage and pre-slaughter handling on pork quality

Forty-eight crossbred (Large White × Landrace) boars were used in a 2 × 2 factorial design to determine the effects of mixing unfamiliar pigs during lairage and the use of electric goads just prior to slaughter on muscle glycogenolysis and subsequent pork quality. The treatments included 2 mixing treatments (familiar pigs kept together during lairage and unfamiliar pigs mixed during lairage) and 2 handling treatments [minimal handling and negative (electric goad) handling pre-slaughter]. Pigs mixed during lairage had lower muscle glycogen and lactic acid at 5 min, 40 min, and 24 h post-slaughter than familiar pigs kept together during lairage. Mixing of unfamiliar boars also resulted in higher ultimate muscle pH, a higher incidence of dark, firm, dry (DFD) pork, and a lower incidence of pale, soft, exudative (PSE) pork compared with familiar pigs kept together during lairage. The use of an electric goad prior to slaughter did not affect muscle glycogen in mixed pigs, but in unmixed pigs there were large numerical diffferences in glycogen concentrations. The negatively handled unmixed pigs had a trend for lower glycogen concentrations which did not reach significance. This was probably due to the small sample size. However, pigs negatively handled pre-slaughter had higher lactic acid concentration at 5 min post-slaughter compared with minimally handled pigs. This experiment has demonstrated that mixing of unfamiliar boars can have a major impact on pork quality, resulting in a high incidence of DFD pork and a reduced incidence of PSE.

Design and application of a cusum quality control chart suitable for monitoring effects on ultimate muscle pH

The cumulative sum, or cusum, chart is introduced for on‐farm monitoring of meat quality traits. The average time over which production is satisfactory or in control (average run length) is defined for the cusum chart and the calculation of this statistic discussed. Data from 9958 Angus and Hereford steers slaughtered at Manawatu Beef Packers (AFFCO) between February 1993 and February 1994 were used to calculate fixed effects and a frequency distribution representing uncontrollable variation in ultimate muscle pH. A cusum chart for on‐farm monitoring of ultimate muscle pH is constructed from this information. A procedure is given for correcting the cumulative sums of unequal sample sizes to a measure suitable for on‐farm monitoring of traits of interest. The role of the cusum chart as an objective tool in farm monitoring programs is discussed, especially for applications of improvement in the quality of carcasses supplied by a farmer to a meat processor.

An analysis of data relating to pig carcass quality and indices of stress collected in the European union

Information from about 5500 pigs killed in five European countries was used to examine the relation of different measures of carcass and meat quality to one another and their relation to biochemical indices of stress in blood collected at slaughter. There were large differences in the prevalence of potentially PSE meat in pigs from the five countries and evidence of a wide range of stress encountered at slaughter. Relationships between the same measurements made in different muscles were generally good and consistent between countries. There were no apparent relationships between indices of stress and characteristics associated with PSE meat. In contrast, greater stress tended to be reflected in more DFD meat. Based on the association between the level of skin blemish and increased muscle ultimate pH values a probable factor contributing to this was fighting between mixed groups of unfamiliar animals.

The effect of fat-enriched diets on the perirenal fat quality and sensory characteristics of meat from rabbits

Two hundred and eighty four medium sized young rabbits were fed ad libitum with two fat-enriched experimental diets (V: vegetable fat, A: animal fat) and a control diet (C). Diet had a significant effect on the ultimate pH (pHu) of the Longissimus dorsi muscle and on the colour, weight and fatty acid composition of the perirenal fat. The carcasses from diet C had significantly less perirenal fat (14.2 g) compared to the carcasses from group A and V (24.4 and 23.0 g) using carcass weight and age of the animals as covariables. Supplementing the diet with animal fat produced perirenal fat which was richer in oleic acid (41%) than in groups V (20.9%) and C (27.9%). The P:S ratio was higher in group V (2.45) compared with groups A and C (0.53 and 0.42). Diet also affected the organoleptic quality of the loin meat. The meat from groups V and C was considered to have a more aniseed flavour than that from group A. In contrast the loin meat from group A had more liver flavour. Both groups V and A were considered juicier than group C. No differences were found in hardness, chewiness and fibrousness. These results suggest than from a human health point of view, the use of a diet supplemented with animal fat is useful on the basis of the nutritional index, P:S of the perirenal fat. However the amount of fat added in the diets V and A should be less than used in this study if the carcass is sold whole in order to avoid excessive perirenal fat. From an organoleptic point of view, the greater aniseed and grass flavour of group V compared to group A may give meat of better sensory quality.

Potential effect of vibration during transport onglycogen reserves in broiler chickens

Subjection of broiler chickens to random, narrow band vibration (2, 5, 10 Hz) for 1 h, simulating that experienced during normal road transport, did not significantly influence liver or muscle glycogen concentrations or muscle ultimate pH (pHu). Vibration for 3 h increased body temperature (P<0.05) and decreased (P<0.01) pHu in both 'white' pectoralis superficalis (PS) and 'red' biceps femoris (BF) muscles overall, but did not affect liver or muscle glycogen concentrations. However, higher vibration frequencies resulted in reduced (P<0.05) glycogen concentrations in liver and BF muscle. The conclusion was that vibration was unlikely to be the major cause of muscle glycogen depletion seen in transported broilers, but the reduction in pHu in the PS muscle after vibration may have been related to the similar effect seen in previous studies after normal transport.

The effect of nutrition and exercise in carcass parameters and the level of glycogen in skeletal muscle of Merino sheep

This study investigated the effects in sheep of feed intake and exercise training on (i) the level of glycogen in muscle, and (ii) carcass quality traits including growth rate, carcass weight, fat score, and the ultimate pH of muscle. Merino wethers, 12-months-old and starting body weight 38 kg, were individually penned and housed indoors. The effects of nutrition and exercise were tested for 2 levels of activity (sedentary v. exercised) and 4 levels of feed intake (1, 1.3, 1.5, 2.2 x maintenance) with 8 sheep per group housed individually. Exercise training was for 1 h at 8-9 km/h (approx. 55-65 VO2max), 3 times per week from week 4 to 9 of the experiment. The diet was 20% cereal straw, 26% lupin grain, 53% barley grain, mineral and vitamin premix, and virginiamycin. Animals were slaughtered at an abattoir in week 10. Regular exercise reduced growth rate, carcass weight, and fat score, but did not affect intake. At the highest level of intake, carcass weight was reduced by 0.53 kg and fat depth over the 12th rib (GR fat depth) by 6.3 mm, suggesting that muscle yield was increased. At all sampling times, the level of glycogen in the m. semimembranosis (SM) and m. semitendinosis (ST) increased linearly with increasing feed intake. Regular exercise caused increased glycogen level in SM samples immediately post-slaughter and in the SM, ST, and m. longissimus dorsi (LD) 48 h post-slaughter. The ultimate pH of muscle was reduced as the level of feed intake increased for all muscle groups. Exercise caused a reduction in the ultimate pH of the ST with no change for the SM and LD. The results indicate that glycogen levels in muscle are highly responsive to nutrition and regular exercise. In addition, exercise caused a reduction in subcutaneous fat with no change in feed intake.

Pasture species effects on carcass and meat quality

Increasing concerns about food quality and animal fat in the human diet have promoted research into the effects of different forage species on carcass quality and fat content. This trial investigated the effect on carcass composition and the intensity of sheep meat flavour and odour of five different pure pasture species: Grasslands Lancelot plantain (Plantago lanceolata), Grasslands Puna chicory (Cichorium intybus), Grasslands Huia white clover (Trifolium repens), Grasslands Nui high-endophyte perennial ryegrass (Lolium perenne) and Grasslands Goldie lotus (Lotus corniculatus). Although pasture species did affect meat quality and fat content, there appeared to be an inverse relationship with carcass weight: larger lambs had more fat, which was related to difference in body size and relative maturity rather that pasture species. Pasture species also influenced muscle ultimate pH, sheep meat odour, foreign odours, and flavours, but did not affect sheep meat flavour. Keywords: Cichorium intybus, meat flavour, Lolium perenne, Lotus corniculatus, meat odour, Plantago lanceolata, Trifolium repens