The relationship between the chemical composition of the carcass and the fatty acid composition of intramuscular fat and backfat of several pig breeds slaughtered at different weights

Pigs of Belgian Landrace (B), Duroc (D), Hampshire (H), and Pietrain (P) breeds were slaughtered at 90, 110 and 130 kg body weight (BW) and the carcass chemical composition and fatty acid profiles of intramuscular fat of loin and backfat were determined. The carcass of Pietrain pigs had a higher concentration of protein and less fat than of B, D and H breeds. In tissues, the PUFA:SFA ratio was lower in the heavier (130 kg BW) than in lighter pigs (90 and 110 kg BW). This feature was higher in P pigs compared with the other breeds. The backfat had a higher concentration of PUFA:SFA ratio than intramuscular fat. The PUFA n− 6:n− 3 ratio was not affected by the breed and weight of pigs, but it was lower in backfat than in longissimus muscle fat. The protein concentration in the carcass was positively related to PUFA and negatively to SFA concentration in tissues.     

Relationships between bacon grade schedules and carcass characteristics

A computer model was used to compare alternative bacon grade schedules in terms of the carcass composition, joint proportions and simple meat quality characteristics (muscle pH and light reflectance) of pigs in different grades. The data used were for 350 side-dissected carcasses from years 6 to 8 of the Meat and Livestock Commission's Commercial Pig Evaluation. Analyses were carried out separately for restricted-fed and ad libitum-fed pigs. Overall means and standard deviations for carcass weight and lean percentage were 64·4 ± 3·19 and 51·5 ± 3·98 (restricted) and 65·1 ± 3·57 and 49·9 ± 4·09 (ad libitum). Alternative schedules were compared against a base schedule, typical of commercial practice in Great Britain and involving the following requirements for the principal grade: a maximum P(2) measurement (taken laterally over the M. longissimus) of 15 mm, maximum mid-line fat measurements (shoulder/loin) of 42 22 mm and a minimum side length of 770 mm. Removal of the shoulder/loin and length requirements increased the proportion of pigs in the principal grade by seven percentage units with little effect on the mean carcass characteristics of pigs in the grade. An extreme tightening of the maximum shoulder/loin measurements to 35 15 mm removed half the pigs from the principal grade and increased the mean carcass lean content and the lean content of individual joints for pigs in the grade by one to two percentage units. Introduction of a minimum muscle thickness measurement of 55 mm had a similar effect. In both cases the effect was partially mediated through a general reduction in fatness and could be achieved by tightening the maximum P(2) fat thickness. None of the changes in grade schedules examined materially altered the mean meat quality characteristics of pigs in the principal grade. The analysis illustrates the complexities involved in using grade thresholds based on a number of correlated measurements. The use of a multiple regression approach, in which carcass lean content and commercial value are estimated from measurements known to contribute significantly to the regression, would simplify the situation considerably.     

Relationships between carcass quality parameters and genetic types

It is important for the meat industry, including pig farmers and breeding companies, to know the composition of the carcass including the proportions of the different commercial cuts when making decisions on the type of pigs to be produced and marketed. Carcass composition is influenced significantly by the genotype of the animals. The aim of this work was to characterise carcasses from five different pig genotypes, by means of the quantification and comparison of their physical composition. Carcasses from 500 gilts from five different genetic types were studied. These lines were based on the following breeds: Large White, Landrace, Duroc, Piétrain and a Meishan synthetic population developed from a cross with a Large White based line. Measurements were taken in the carcasses directly with a ruler and with the Fat-O-Meat'er. The carcasses were cut following the European reference method and the four main joints were dissected. Carcasses from the Piétrain based line, which was halothane negative, presented the highest killing-out (83.34%) and were the shortest (81.81cm). The Piétrain based line was also the leanest and the Meishan based line the fattest. The highest proportion of ham (270.9g/kg) and the lowest proportion of belly (97.97g/kg) were found in the Piétrain line. The proportion of lean in all of the dissected cuts was higher in carcasses from this line while the Meishan line presented the highest proportions of intermuscular fat in all of the pieces. Carcasses came from the Piétrain line received the highest conformation scores and they were leaner and with better ham yield.     

Relationship of physically separable lean with chemical lean in pig carcasses

This study was conducted to examine the relationships between 'physically separable lean' (carried out by the Kulmbach reference technique) and 'lean' determined by moisture or lipid analysis (called chemical lean). Five major cuts (ham, shoulder, loin, belly and neck), originating from the Hungarian cross-breed 'Hungahyb', were dissected and the weights recorded. The moisture and lipid contents of three tissue groups (lean, intermuscular fatty tissue and remainder) were determined by common laboratory methods. Adequate estimators (predictors) were then developed for the assessment of standardized or non-standardized lean content in the 'boneless cut' (without skin and subcutaneous fatty tissue). It was shown that the concept of moisture-standardized lean is analogous to that of the fat-standardized one. It appears that unbiased estimators could be obtained if the interdependences between the chemical composition (moisture or lipid content) of the lean, the 'residue' (intermuscular fatty tissue + remainder) and that of the 'boneless cut' are included in the respective equations. If these interdependences are neglected and only the corresponding means are used in these equations, biased estimates have been obtained for the standardized or non-standardized lean content in the 'boneless cut'. Difficulties arising at practical application of these concepts are also discussed in this paper.     

肌内脂肪与背最长肌肉质、脂肪酸组成的关系

研究肌内脂肪（IMF）含量与肉质以及脂肪酸含量和组成比例之间的关系。以北京黑猪背最长肌（n=20）为实验材料,测定肌内脂肪含量、肉质以及脂肪酸含量和组成。结果显示,肌内脂肪含量与滴水损失呈显著正相关（p<0.05）,与蒸煮损失、剪切力、肉色的相关性不显著（p>0.05）。随着肌内脂肪含量升高,除长链多不饱和脂肪酸(C_20:3n6、C_20:4n6)以外的大多数脂肪酸含量增加,相对比例也上升;多不饱和脂肪酸的含量增加,但是相对比例下降;长链多不饱和脂肪酸的含量和相对比例都降低。随着肌内脂肪含量的升高,饱和脂肪酸（SFA）和单不饱和脂肪酸（MUFA）的含量升高,回归方程斜率分别为197.3和248.31,多不饱和脂肪酸（PUFA）增加的幅度不大,回归方程的斜率为11.43。结果提示:肌内脂肪含量较低时（本实验平均值2.86%）,对肉质的影响不显著。随着肌内脂肪含量升高,总脂肪酸含量（TFA）增加,主要归因于SFA和MUFA含量的增加。PUFA的含量相对稳定,受肌内脂肪含量变化的影响较小。      

Relationships between beef carcass shape and muscle to bone ratio

Relationships between muscularity and muscle to bone ratio were investigated for beef carcasses of several breeds and crosses, and three genders using data from Bristol and Alberta. Side dissection data in terms of muscle, fat and bone weights were used to calculate muscle to bone ratios (MtoB) and muscularity indexes (MUSC) for the whole side or for the region around the femur bone. Highly significant breed and gender effects on MtoB and MUSC were shown for both the Bristol and the Alberta data sets, but the group differences for MtoB were not the same as those for MUSC despite the fact that these two characteristics were closely correlated. For both sets of data, for example, MUSC values at a common muscle plus bone weight were significantly higher for carcasses of bulls than heifers, but similarly adjusted MtoB values were generally higher for carcasses of heifers than bulls. Differences among breed groups were mainly in a similar direction for MUSC and MtoB, but the size of the differences varied widely. For example, relative to the Friesian, the Jersey breed had a significantly higher MtoB but a significantly lower MUSC, and carcasses of double-muscled bulls had a femur-region MtoB that was 19.2% greater than that of a group of Shorthorn-cross carcasses, but a MUSC that was only 1.7% higher. These findings show that because of the inconsistent relationships between muscularity and muscle to bone ratio among different classes of beef carcasses, lean meat yield cannot always be predicted without bias if measures of carcass shape are used as indicators of muscle to bone ratio.     

我国部分典型植烟区土壤腐殖质组成特征及其与部分土壤因子的关系

分析了我国部分典型植烟区土壤腐殖质组成特征及其与部分土壤因子的关系,结果表明:(1)在所考察的典型烟叶产区中,植烟土壤腐殖质碳量集中分布在10-20 g/kg之间,平均为15.25 g/kg.胡敏酸比例、富里酸比例、胡敏素比例分别分布在11.05%-32.15%、12.00%-36.28%、38.43%-68.23%之间,胡富比值集中分布在0.7-1.3之间.(2)腐殖质碳量以东南烟区显著较高,黄淮烟区显著较低;胡富比以东南烟区显著较高,胡富比值达1.14,其它烟区土壤胡富比小于1.(3)水稻土腐殖质及组分碳量均最高,紫色土、红壤、棕壤次之,褐土最低.水稻土腐殖化程度显著较高,棕壤和红壤腐殖化程度显著较低.(4)土壤pH与腐殖质组成整体呈显著负相关关系.土壤的富里酸比例越低、胡富比越高,土壤碱解氮含量呈升高趋势.     

Dual X-ray absorptiometry accurately predicts carcass composition from live sheep and chemical composition of live and dead sheep

Fifty merino wethers (liveweight range from 44 to 81kg, average of 58.6kg) were lot fed for 42d and scanned through a dual X-ray absorptiometry (DXA) as both a live animal and whole carcass (carcass weight range from 15 to 32kg, average of 22.9kg) producing measures of total tissue, lean, fat and bone content. The carcasses were subsequently boned out into saleable cuts and the weights and yield of boned out muscle, fat and bone recorded. The relationship between chemical lean (protein+water) was highly correlated with DXA carcass lean (r(2)=0.90, RSD=0.674kg) and moderately with DXA live lean (r(2)=0.72, RSD=1.05kg). The relationship between the chemical fat was moderately correlated with DXA carcass fat (r(2)=0.86, RSD=0.42kg) and DXA live fat (r(2)=0.70, RSD=0.71kg). DXA carcass and live animal bone was not well correlated with chemical ash (both r(2)=0.38, RSD=0.3). DXA carcass lean was moderately well predicted from DXA live lean with the inclusion of bodyweight in the regression (r(2)=0.82, RSD=0.87kg). DXA carcass fat was well predicted from DXA live fat (r(2)=0.86, RSD=0.54kg). DXA carcass lean and DXA carcass fat with the inclusion of carcass weight in the regression significantly predicted boned out muscle (r(2)=0.97, RSD=0.32kg) and fat weight, respectively (r(2)=0.92, RSD=0.34kg). The use of DXA live lean and DXA live fat with the inclusion of bodyweight to predict boned out muscle (r(2)=0.83, RSD=0.75kg) and fat (r(2)=0.86, RSD=0.46kg) weight, respectively, was moderate. The use of DXA carcass and live lean and fat to predict boned out muscle and fat yield was not correlated as weight. The future for the DXA will exist in the determination of body composition in live animals and carcasses in research experiments but there is potential for the DXA to be used as an online carcass grading system.     

Texture of cooked potato II.—Relationships between intercellular adhesion and chemical composition of the tuber

In the variety Majestic, statistically significant relationships were found between intercellular adhesion and the levels of tuber starch, amylose, polyuronide, calcium and magnesium. It is suggested that the relationship between intercellular adhesion and a particular constituent may be modified by the levels of the other constituents. a mechanism is proposed for the action of amylose in influencing intercellular adhesion. the differences in intercellular adhesion, and in the levels of the various intrinsic factors, were produced by feeding plants different nutrient solutions (various chloride/nitrate ratios) or by maintaining different moisture regimes.     

Effect of source of dietary fat on pig performance,carcass characteristics and carcass fat content,distribution and fatty acid composition

Seventy gilts were used to compare the effect of including 10% tallow (T), high-oleic sunflower oil (HOSF), sunflower oil (SFO), linseed oil (LO), a fat blend (FB), or an oil blend (OB) in finishing diets vs. feeding a semi-synthetic diet with no added fat (NF) on pig performance, carcass traits and carcass fatty acid (FA) composition. Carcasses from SFO-fed gilts had greater fat and lower lean compositions than carcasses from T-fed gilts. Gilts fed NF had greater loin fat than FB-fed gilts, and greater flare fat, loin intermuscular fat and fat:lean than T-fed gilts. Bellies from NF-fed gilts had lower lean and higher intermuscular fat and fat:lean than other diets except HOSF. Fat source had minor effects on animal performance, carcass characteristics and carcass fat content and distribution, whereas feeding NF resulted in carcasses and major cuts with higher fat content. Diets rich in polyunsaturated FA (PUFA) did not reduce fat deposition in separable fat depots with respect to monounsaturated FA (MUFA) and saturated FA (SFA). Carcasses from gilts fed NF had a high degree of saturation (40.6% SFA) followed by carcasses of T- and FB-fed gilts. Feeding HOSF, SFO and LO enriched diets elevated the percentages of MUFA (56.7%), n−6 (30.0%) and n−3 (16.6%) PUFA, respectively, whereas carcasses from gilts fed OB had greater percentages of n−3 FA (14.8% n−3, 0.9% EPA, 1.0% DPA, 3.1% DHA) than gilts fed FB (6.72% n−3, 0.1% EPA, 0.4% DPA, 0.1% DHA).     

猪胴体瘦肉率仪器测定值与生猪品种等级的关系研究

使用PG100瘦肉率测定仪,对四种不同品种等级的生猪屠宰后的胴体的瘦肉率进行了测定,并与精确分割试验测定的瘦肉率进行了比较。结果表明使用仪器测定的瘦肉率指标,能够较好地反映生猪品种等级的优劣,可以用于生猪屠宰过程中的智能分级。     

猪胴体加工工艺与设备

根据猪胴体加工工艺,重点介绍在胴体加工过程中的输送、旋毛虫检验、同步检验、劈半等工艺及设备,同时,笔者结合多年的实践经验,提出了一些见解及操作方法.     

The relationship between carcass, meat and eating quality of three pig genotypes

The relation between the intrinsic carcass and meat quality and the organoleptical characteristics of three genotypes of pigs was studied. In total 411 pigs, consisting of 121 BL-genotype pigs, 115 hybrids (Seghers Hybrid) and 175 Large White-genotype pigs, were screened. Slaughter day and genetic background had a great impact on the intrinsic meat quality parameters. The factor 'slaughter day' implies the stunning method besides the total specific transport and slaughter conditions. Whatever the genetic background is, halothane susceptibility is obviously the crucial factor. Selection against the halothane gene positively influences the intrinsic and sensory meat quality parameters. This study also suggests that an increase in the intramuscular fat content, if desirable in the interest of the sensory meat quality, can be achieved without deterioration of the zoo-technical performance and the carcass quality of the pigs.     

Fatty acid composition of Celta pig breed as influenced by sex and location of fat in the carcass

BACKGROUND: The influence of sex and location of fat in the carcass on the fatty acid profile of Celta pigs was studied. Twenty pigs (10 castrated males and 10 females) from the Carballina line were used. RESULTS: The fatty acids composition was predominated by monounsaturated fatty acids (MUFA; approximately 48% of total methyl esters), followed by saturated fatty acids (SFA; approximately 40% of total methyl esters) and, finally, polyunsaturated fatty acids (PUFA; approximately 12% of total methyl esters). The sex and location of fat in the carcass showed significant differences in PUFA and SFA content while both factors were not significantly different with respect to MUFA content. Linoleic, linolenic, eicosatrienoic and arachidonic fatty acids showed the largest difference among the three locations (intramuscular, subcutaneous ventral and subcutaneous dorsal) of the fat in the carcass. CONCLUSION: The fatty acid profile that we observed in the fat of the Celta pigs does not differ greatly from those described by other authors in other autochthonous pig breeds. Principal component analysis offered a good separation of the mean samples according to the sex and location of fat of the pigs. Copyright © 2011 Society of Chemical Industry     

Evaluation of live and carcass techniques for predicting beef carcass composition

Fifty beef animals varying in size, age and composition were used to determine the most accurate methods for determining beef composition. Separable and chemical composition of the 9-10-11th rib section and measurements of subcutaneous fat thickness were the most useful for explaining observed variability in carcass composition. For predicting percentage fat in fed steers, composition of the 9-10-11th rib section was the most accurate [coefficient of determination (R(2) 0·85)]. The 9-10-11th rib section was the most accurate and precise technique identified in this study to estimate beef carcass composition across and within all age classes. Specific gravity accounted for 68% of the variation in percentage of carcass fat across all age classes combined; however, specific gravity did not account for a significant portion of the variation within each age class. Deuterium oxide dilution was able to account for 77% of the variation in chemical fat percentage across all age classes combined; however, deuterium oxide dilution was not as effective in accounting for the observed variation in fat percentage within each age class. Ultrasound was found to be an accurate live measure of chemical fat percentage within all age classes combined.     

Prediction of carcass composition in the rabbit

Carcass composition of two synthetic rabbit breeds was predicted from retail cuts and external measurements by using regression equations. Breed R has a higher adult weight and reaches slaughter weight 1 week before breed V. Sixty rabbits of each breed were slaughtered when they (approximately) reached the Spanish commercial liveweight of 2kg. The carcasses were measured and retailed according to the norms of the World Rabbit Scientific Association. Rabbit carcass composition is well defined by meat percentage of the commercial carcass and ratio meat bone . External measurements on the carcass, retail cuts and meat of retail cuts or muscular masses are all bad predictors of carcass meat percentage or ratio meat bone (R(2) < 0.53). The ratio meat bone of the hind leg can give reasonable predictions for carcass meat percentage and meat bone ratio (R(2) = 0.60 and 0.69). Dissectible carcass fat weight and dissectible carcass fat percentage can be predicted by the perirenal fat weight (R(2) = 0.77 and 0.69). Fat depots had a low predictive power for fat percentage of the dissected meat in the half carcass.     

卷烟燃烧包灰与烟丝化学成分的关系

为揭示卷烟燃烧包灰与烟丝化学成分的关系,利用卷烟包灰检测仪测定了 84种卷烟样品在ISO抽吸条件下的灰色值、裂口率、缩灰率、炭线宽度、炭线整齐度和燃烧速率,并采用统计分析方法研究了卷烟包灰指标和燃烧速率与烟丝化学成分之间的关系.结果表明:①钾元素质量分数(αK)、钾氯元素质量比(mK/mCl)、钾硫元素质量比(mK/m...     

Prediction of carcass composition and individual carcass cuts of Japanese Black steers

The objective of this study was to develop equations to predict carcass tissue weights and percentages and boneless carcass non-trimmed cut weights by using the cold carcass weight (CCW) and three other traits at the 6–7th rib section, which are routinely collected in carcass markets in Japan. Carcasses from 94 Japanese Black steers were used for the multiple regression analysis with a stepwise procedure and a novel Least Absolute Shrinkage and Selection Operator (LASSO). The accuracies of prediction (R²) and RMSEs for the carcass tissue and cut weights were similar between the two procedures. In contrast, LASSO appeared to be the better procedure for predicting carcass tissue percentages. The longissimus muscle area and subcutaneous fat thickness were the important predictors for the lean percentage in the stepwise procedure, and CCW was additionally selected when the LASSO procedure was used.