Effect of pre- and post-pubertal castration on Piemontese male cattle. II: Carcass measures and meat yield

The effect of different castration ages on carcass morphological characteristics, meat yield, commercial cuts and bones weight and measures was evaluated on Piemontese steers and bulls. Carcasses (24) obtained from early castrated (EC, 5th month of age), late castrated (LC, 13th month) and intact males (IM, control group) of similar age (about 18 months) and fattening degree, were weighed, measured and dissected following the local commercial method. Very few differences were found in carcass conformation and fatness as in carcass weight and measures. After data adjusting, few meat cuts were heavier in IM compared to EC and LC, and only one cut measure was different, whereas, almost no differences were found in bone measures and weight. IM produced carcasses with more edible meat than LC and more forequarter and 2nd quality meat than LC and EC. Significant differences were found also between total, hindquarter and perinephric fat.     

The use of principal component analysis (PCA) to characterize beef

Principal component analysis was performed to study the relationships between chemical, physical and sensory variables (n=18) measured on longissimus thoracis et lumborum of 79 young bulls from the following ethnic groups: hypertrophied Piemontese, normal Piemontese, Friesian, crossbred hypertrophied Piemontese×Friesian, Belgian Blue and White. The first three PCs explained about 63% of total variability. Sensory characteristics, protein content, shear force and cooking losses resulted the most effective variables for the PC1, while hydroxyproline and ether extract content, as well as hue and lightness were useful to define the PC2. The distribution of the objects on the axes of the first two PCs allowed the identification of two groups, the first one including meats of the hypertrophied animals (Piemontese and Belgian Blue and White) the second one including normal Piemontese and Friesian. However, a considerable variability within groups was noted. The crossbreds were placed between the two previous groups. In conclusion, PCA proved to be a very effective procedure to obtain a synthetic judgement of meat quality.     

Variation of the sensory quality within the m. longissimus thoracis et lumborum of PSE and normal pork

This study evaluated the variation in instrumental and sensory meat quality within the m. longissimus thoracis et lumborum of carcasses with normal and PSE meat. Out of 80 slaughtered pigs, respectively, 9 and 7 carcasses were selected with a pH30 value > or=5.80 (normal pork) and a pH30 value <5.80 (PSE pork). Instrumental and sensory meat quality measurements were performed at three locations on these carcasses: longissimus thoracis (LT), longissimus thoracis et lumborum: (LTL-mid-loin) and longissimus lumborum (LL). Meat of the thoracis site (LT) was paler, but more favourable for pH45, cooking loss, juiciness, tenderness and preference scores than meat of the mid-loin part. The lumborum site (LL) was more or less in between the other two locations for meat quality, but closer to the LTL than the LT site. The meat quality variation within the m. longissimus thoracis et lumborum followed a similar pattern for normal and PSE carcasses. It can be concluded that the mid-loin part is best suited as a reference place for meat quality assessment, if one wants to eliminate carcasses with unacceptable meat.     

Carcass and meat quality in double-muscled Belgian Blue bulls and cows

Carcass and meat quality of 37 bulls and 91 cows of the Belgian Blue breed (double-muscled type) were compared. Age at slaughter averaged 648±73 and 1820±689 days, respectively. Both groups of cattle were finished on maize silage supplemented with concentrate, and were slaughtered at about 750 kg live weight. Females had a lower (P=0.004) cold carcass weight (469.7 kg) in comparison with bulls (500.8 kg), due to a reduced dressing percentage (63.8 vs. 66.6; P <0.001). SEUROP conformation was better for bulls. SEUROP fat covering (P=0.007) and fat content in the carcass (16.4 vs. 12.9%; P <0.001) and in the M. longissimus thoracis (LT) muscle (2.3 vs. 1.1%; P <0.001) were higher for females than for males. The LT of cows was darker (lower L* and higher a*-value; P <0.001), had a better waterholding capacity (P?0.063) and was slightly more tender (P=0.120) than the LT of bulls. Increasing parity reduced dressing percentage and increased LT lightness (L*-value) in cows. Several carcass (SEUROP-grading, composition, LT-area) and meat quality traits (protein and fat contents, drip and cooking losses, a*-value) were better correlated with carcass weight than parity. It is concluded that meat quality of the aged LT of cows is not negatively affected by age, while some carcass quality traits decreased with advancing age. Carcass quality traits adjusted for age at slaughter were better for bulls, but LT meat quality characteristics were at least as good for females as for males.     

Growth and carcass characteristics of pasture fed LHRH immunocastrated, castrated and intact Bos indicus bulls

The effectiveness of a luteinizing hormone-releasing hormone (LHRH) fusion protein vaccine or surgical castration, at two years of age, on growth and carcass characteristics of Bos indicus bulls was evaluated. Seventy Nelore-cross bulls were divided into three groups: (1) immunized, (2) castrated and (3) intact control. At slaughter (three years of age), intact bulls had higher body weights, ADG, carcass weights, and muscle percentage compared to immunized and surgically castrated animals. Both castrated and immunized animals had greater marbling and percent carcass fat than the intact bulls. Average tenderness scores were inferior for intact bulls compared to immunized and castrated animals, but these differences were not significant (P>0.05). Juiciness, flavor, thawing, nor cooking losses differed significantly among the three groups. Immunocastration was effective in producing carcass traits similar to that of surgical castration. Therefore, immunization with LHRH fusion proteins appears to have practical utility in the management and castration of grazing bulls.     

延迟冷却对牛肉品质及超微结构影响的研究

本文研究了常规冷却与延迟冷却对中国杂交黄牛(鲁西黄牛×西门塔尔)宰后冷却过程中牛胴体pH值、温度变化、胴体冷却失重、肉色及成熟过程中剪切力值、背最长肌汁液损失、蒸煮损失、保水性、肌原纤维结构变化的影响.结果表明延迟冷却能减缓牛胴体温度的下降速率(P＜0.05),加快牛胴体pH值的降低(P＜0.05),提高牛背最长肌的嫩化速率,改善肉色(P＜0.05),但加剧了汁液损失、蒸煮损失,降低了保水性(P＜0.05).延迟冷却对成熟0d、3d时的肌原纤维结构影响显著(P＜0.05),延迟冷却组的肌节长度明显长于对照组的肌节长度.     

EFFECTS OF PHYSIOLOGICAL MATURITY OF BEEF AND MARBLING OF RIB STEAKS ON EATING QUALITY

SUMMARY— Selected characteristics of beef rib steaks representing three physiological maturity levels and two marbling levels were investigated. Paired steaks at the 1lth thoracic vertebra were used to obtain cooking time and losses, palatability scores, Warner-Bratzter shear values, and selected histological data. In addition, steaks from the left 7th and right 8th thoracic vertebrae positions were used to measure cooking time and losses, Warner-Bratzfer shear values, waterholding capacity, pH, color-difference, and total moisture. Ether extract was obtained for raw longissimus dorsi at the 12th thoracic vertebra. Maturity and marbling affected told moisture (P < 0.001), quantity of fat in raw muscle (histological measurement, P < 0.01). ether extract (P < 0.001). and dripping losses (7th and 8th thoracic vertebrae P < 0.001). Other factors were not affected significantly. Maturity and marbling, at levels represented, had little effect on palatability of the steaks, although generally, measurements for fat content were higher and those for moisture lower at the higher marbling level. Most correlation coefficients for overall acceptability and histological measurements were low. Tenderness had more influence on the overall acceptability of the meat than flavor or juiciness. Moderate to high relationships occurred between cooking time and both initial weight of steaks and cooking losses. Generally, waterholding capacity was not related to pH, total moisture, or cooking losses. Correlation coefficients for pH vs. shear value and pH vs. color-difference were low.     

The effect of dietary poultry litter supplementation on beef chemical, cooking, and palatability properties and consumer acceptance

Twenty Holstein steers were randomly and equally allocated to two groups (treatment and control) at a mean weight of 334.3 kg and were backgrounded for 133 days and fed a finishing diet for 99 days under commercial conditions. Control animals received 97.1% corn silage, 2.6% canola meal, and 0.3% mineral mix during backgrounding and 72.6% corn silage, 3.9% canola meat, 23% barley and 0.2% mineral mix during finishing. Treated animals received 95.3% corn silage, 4.4% poultry litter, and 0.3% mineral mix during backgrounding and 62.1% corn silage, 5.6% poultry litter, 22% barley, and 0.2% mineral mix during finishing. The poultry litter was provided as a pelleted. At the end of the finishing period, all animals were harvested. After 144 h at 2 °C, the boneless longissimus thoracis et lumborum muscles were removed, cut into steaks (1.9 cm thick) and roasts, vacuum packaged, and frozen. A steak adjacent to the 13th thoracis vertebra of alternate carcass sides was displayed under simulated retail conditions for 4 days and then analyzed for moisture and fat content. A steak immediately posterior to the 13th thoracis vertebra of alternate carcass sides was evaluated by an experienced trained six-member laboratory panel for palatability attributes. The steak immediately posterior to the steak used for sensory evaluation was used for shear force evaluation. A roast constituting the reminder of the longissimus lumborum muscle was used to obtain complete flavour and texture profiles. Total cooking losses were determined and cooking times were recorded for both steaks and roasts. All remaining steaks (1180) were distributed at random to households to determine consumer acceptance. Treated samples were essentially indistinguishable from control samples in both palatability and consumer acceptance, indicating poultry litter supplements can be utilized in feedlot rations for cattle without compromising either palatability or consumer acceptance.     

Influence of maturation and cooking treatments on the nutritional value of bovine meats: Water losses and vitamin B12

The aim of the study was to determine the influence of maturation and of cooking processes on water losses and on the vitamin B12 content of meat. Three types of muscle (Longissimus lumborum, Longissimus thoracis and Triceps brachii) were sampled from a total of 16 animals, representative of animals raised for meat production in France. Three durations of maturation were compared: 1, 3 and 14 days. Different cooking processes were applied: Longissimus lumborum was deep-fat fried or roasted, Longissimus thoracis was pan fried or grilled and Triceps brachii was braised. The cooking yield averaged 55-56% for Triceps brachii, 73-77% for Longissimus lumborum and 85-87% for Longissimus thoracis. Vitamin B12 concentration in raw meat was significantly higher in Triceps brachii than in Longissimus lumborum and Longissimus thoracis (20.86, 11.53 and 9.21ng/g wet tissue, in the same respective order). When expressed on a wet weight basis, all concentrations were significantly increased by cooking. When expressed on a lipid-free dry basis, significant losses in vitamin B12 were measured only in the braised Triceps brachii (-25%) and in the deep-fat fried Longissimus lumborum (-5.5%) as a result of long duration and high temperature of cooking, respectively. Maturation did not affect the vitamin B12 content of meat, whether raw or cooked.     

EFFECTS OF LATE CASTRATION AND FEEDING TIME ON BOVINE MUSCLE QUALITY

Hereford bulls were late castrated by emasculation at approximately 1 year old or left intact, and fed for 0, 60 or 90 days before slaughter to evaluate various traits of the M. longissimus. More days on feed resulted in increased carcass weight, fat thickness, USDA quality grade, ribeye area and percentage kidney, pelvic and heart fat, with no difference from late castration. Percentage of soluble collagen was highest for M. longissimus steaks from the 60 day feeding group, and lowest among those fed 90 days. Steaks from the controls were lighter colored while those from steers fed 60 days were the most red. No sensory differences occurred except for off-flavor.     

延迟冷却对牛肉品质影响的研究

研究了常规冷却和延迟冷却对中国杂交黄牛(鲁西黄牛×西门塔尔)宰后冷却过程中牛胴体pH、温度的变化、胴体冷却失重、背最长肌汁液损失、蒸煮损失、保水性、肉色及成熟过程中剪切力值的变化。结果表明:延迟冷却减缓了牛胴体温度的降低速率(P<0.05),加快了牛胴体pH的降低(P<0.05);延迟冷却提高了牛背最长肌的嫩化速度,改善了肉色(P<0.05),但增加了汁液损失和蒸煮损失,降低了保水性(P<0.05)。因此,优化延迟冷却程序是必要的。     

Higher drip loss is associated with protein oxidation

The study aimed to investigate the mechanisms underlying drip loss in meat other than those related to post mortem energy metabolism. The study was carried out on M. longissimus thoracis assessing carcass and meat quality traits plus metabolic parameters and drip loss. Based on the data obtained, three drip loss groups were established: low, medium and high. Heat treatments were performed at 100 °C for 30 min. Physicochemical protein modifications were assessed before and after cooking. IMF and L* were higher in the high drip loss group, whereas b* was higher in the medium drip loss group. Residual glycogen, glucose and glycolytic potential were higher in LT muscle from the high drip loss group. Before cooking, protein surface hydrophobicity and carbonyl levels were similar in the three groups. However, after cooking, carbonyl, oxidized actin and oxidized aggregates were higher in the high drip loss group, suggesting that protein oxidation may affect the water holding capacity of meat.     

The effects of gender and castration of females on performance and carcass and meat quality of heavy pigs destined to the dry-cured industry

The effects of gender and castration of females (IF, intact females; CF, castrated females; CM, castrated males) on performance and carcass and meat quality were studied in crossbred pigs (Landrace × Large White dams × Duroc sires) slaughtered at 119.2 (experiment 1) or 131.6 (experiment 2) kg body weight. Intact females had better feed conversion and less carcass fat than CF and CM. Trimmed shoulder yield was higher for CM than for CF with IF being intermediate. Primal cut yield and meat quality were similar for all treatments. Proportion of linoleic acid in backfat was lower in CF than in IF or CM and the differences were significant when pigs were slaughtered at 131.6 kg. The higher fat content and the fatty acid profile favor the use of castrated females and males over intact females for the production of heavy pigs destined to the dry-cured industry.     

Castration and slaughter age effects on nutritive value of the "mestiço" goat meat

Groups of castrated male and intact "mesti?o" goats were slaughtered at 175, 220, 265 and 310 days of age. After slaughter the carcasses were chilled for 24 h at 2°C, and pH, Aw, Ca, Fe, P, moisture, ash, protein and fat were determined on the total lean. Slaughter age had a significant (p<0.01) effect on moisture, protein, iron, calcium and pH. Calcium content was influenced by castration and the slaughter age×castration interaction was significant (p<0.01) for iron content. Meat from castrated males contained less moisture and protein and more fat, ash, iron and calcium than did meat from intact males. The fat, protein and iron content increased with increasing slaughter age, while moisture decreased. Composite results indicate slaughtering "mesti?o" goats at 310 days exert favourable effects on the parameters investigated. ?     

Effects of chilling rate and spray-chilling on weight loss and tenderness in beef strip loin steaks

We evaluated the effects of chilling rate and the use of a spray-chilling system on the weight loss by evaporation on carcasses. We also evaluated the effects on meat purge in vacuum package, cooking losses, and on parameters related to the tenderness of strip loin steaks (M. longissimus lumborum). Forty non-castrated males of approximately 12 months old, finished in feed-lot were harvested in 16 Montana cattle (a composite breed), and 24 Simmental × Nellore crossbred cattle. After bleeding, the bodies were electrically stimulated and assigned to one of the four treatments: conventional air-chilling (CAC), conventional spray-chilling (CSC), slow air-chilling (SAC), and slow spray-chilling (SSC). Strip loin steaks (M. longissimus lumborum) of approximately 2.5 cm thick were removed, vacuum packed and aged for 7, 14, 30 or 60 days. Samples were analyzed for sarcomere length, myofibrillar fragmentation index, Warner–Bratzler shear force, and weight losses by purge and cooking. Spraying was efficient in reducing weight loss by evaporation (P < 0.05). Effects of treatments and aging period on purge losses were observed, where samples from sprayed carcasses or aged cuts showed higher losses. Cooking losses were not affected either by spraying or aging. The slow chilling, with or without spraying, was more efficient in producing strip loin steaks with lower average shear force and longer sarcomere. The myofibrillar fragmentation index increased with aging time, but was not affected by carcasses spraying.     

CALCIUM CHELATORS AND SALT EXTRACTED MYOFIBRILLAR PROTEIN INJECTION INTO LEAN PRERIGOR BEEF MUSCLE: EFFECTS ON TENDERNESS INDICES

Prerigor beef longissimus muscles were removed within 40 min postmortem and injected 10% (within 2 h postmortem) with either a chelator (alginate, 3%; haametaphosphate, 3%; EDTA, 0.13%; citrate, 0.13%), meat slurry (45%), or a myofibrillar meat extract (3.7% protein) to evaluate the effects of each injection on the physical and chemical properties compared to a control and a water only injected treatment. Gross muscle shortening was not inhibited The water only, meat extract and citrate treatments had shorter (P<0.05) sarcomeres than the control. The meat shy, alginate, phosphate, and EDTA treatments produced sarcomere lengths equivalent to the control. The control had the lowest (P<0. 05) pH and percentage moisture. However, there were no differences in percentage cooking losses. Although variations in sarcomere length were apparent, these treatments did not improve tenderness (P>0.05) as measured by Warner-Bratzler shear.     

Effect of replacing soybean meal by extruded chickpeas in the diets of growing-finishing pigs on meat quality

The main objective of this study was to evaluate the effect of the replacement of soybean meal by extruded chickpeas in diets of growing-finishing pigs on meat quality. In a 17wk study 48 growing-finishing crossbred pigs were fed ad libitum. The experimental design included four treatments, each one of 12 pigs; the ECKP0 treatment was fed with diet containing soybean meal and no chickpeas (control), while treatments ECKP100, ECKP200 and ECKP300 were fed with diets containing 100, 200 and 300kg/t of extruded chickpeas, respectively. The lean meat quality of the longissimus lumborum et thoracis muscle was evaluated by chemical analysis (moisture, protein, fat and ash), fatty acid profile, pH measurement, cooking loss, color evaluation, and sensory evaluation. Odor and taste, tenderness, juiciness, and overall acceptability were scored on 1-10 scales by a group of 10 experienced assessors after a standard cooking regime. Small differences were observed between control and experimental groups in chemical composition (P>0.05). Fatty acid profiles, pH measurements and color evaluation did not differ among treatments (P>0.05), while cooking loss was significantly lower in the control group (P<0.05). The taste panel gave slightly higher scores for the tenderness and juiciness for the control group compared with the chickpea treatments (P<0.05). No differences were observed between control and experimental groups in taste scores (P>0.05). It is concluded that the replacement of soybean meal by extruded chickpeas, when substituted isonitrogenously and isoenergetically at inclusion levels up to 300kg/t of pig, does not influence significantly meat quality.     

Effect of gender and castration of females and slaughter weight on performance and carcass and meat quality of Iberian pigs reared under intensive management systems

A total of 360 Iberian dam × Duroc sire pigs was used to study the influence of gender and castration of females (CM, castrated males; CF, castrated females; IF, intact females) and slaughter weight (SW; 145 and 156 kg body weight, BW) on performance and carcass and meat quality. Each treatment was replicated four times (15 pigs). Intact females ate less, tended to have better feed conversion and had less carcass fat and more primal cuts yield than CM and CF. Pigs slaughtered at 156 kg BW ate more feed and had worse feed conversion than pigs slaughtered at 145 BW. An increase in SW improved carcass yield, but tended to decrease trimmed ham yield. Intact females are an alternative to castrated females for intensive production of Iberian pigs. Also, the reduction in slaughter weight from 156 to 145 kg BW is recommended for this type of production.     

Sensory characterization of meat from pigs vaccinated against gonadotropin releasing factor compared to meat from surgically castrated,entire male and female pigs

Boar taint is a sensory defect mainly due to androstenone and skatole. The most common method to control boar taint is surgical castration at an early age. Vaccination against gonadotropin releasing factor (also known as immunocastration) is an alternative to surgical castration to reduce androstenone content. In this experiment, loins from 24 female (FE), 24 entire male (EM), 24 vaccinated males (IM) and 23 surgically castrated males (CM) were evaluated by eight trained panellists in 24 sessions. Loins were cooked in an oven at 180 °C for 10 min. Furthermore loins were evaluated by consumers and its androstenone and skatole content were also chemically determined. Meat from EM had higher androstenone and skatole odour and flavour than meat from FE, IM and CM and lower sweetness odour scores. High correlations were found between androstenone and skatole levels assessed by trained panelists, chemical analysis and consumers’ acceptability. Moreover meat from EM is mainly related to androstenone and skatole attributes.     

Recommended terminology for the muscle commonly designated 'longissimus dorsi'

Musculus longissimus of the erector spinae is frequently used by meat scientists because of its relative mass, its commercial importance and its variability in quality. Its designation has fluctuated considerably due to confusion over interpretation of accepted anatomical guidelines, some of which have been altered to improve precision. We recommend that meat and muscle scientists refer to the part of the whole muscle they generally use as the Longissimus thoracis et lumborum (LTL) or to either of its two parts, Longissimus thoracis (LT) or longissimus lumborum (LL), depending on which is referenced. The word dorsi should be omitted, the word musculus (or its abbreviation M.) preceding all muscles in Latin should not be used in English, and the longissimus atlantis, capitis and cervicis should not be included except when they are actually used.