Muscle traits for long matured dried meats

Zinc-protoporphyrin formation in nitrite-free Parma Ham and its relationship with intrinsic parameters and red color profile of processed hams

A total of 134 fresh hams, assayed for Ferrochelatase (FeCH) activity and ultimate pH (pH48), were processed in compliance with the procedures established for PDO Parma ham and finally, analyzed for salt, moisture, Zinc Protoporphyrin IX (ZnPP), heme, iron and zinc contents, and proteolysis index (PI). The variation in ZnPP content was related to the intrinsic parameters of fresh and matured hams by a Partial Least Square Regression model. The most favorable factors on the formation of ZnPP were total iron content (representative of the initial hemoprotein content), and FeCH activity, demonstrating the main role played by these raw matter-specific predictors in the long matured dry-cured hams. To a lesser extent, zinc content and pH48 were involved with a positive and negative role, respectively. Salt content and PI of matured hams showed an inhibitory and a favorable influence, respectively, toward the ZnPP formation. Principal Component Analysis showed the associations between the sensory red color profile and the physicochemical traits of matured hams. The red color intensity increased in agreement with the red-violet and red-pink hues scores. The formation of a high amount of ZnPP was associated with the increased perception of the red-violet shade, with a lower lightness (L*) and Hue angle (h°). Moisture increase contributed to the shift in color perception to red-pink, while marked progress in PI strengthened the perception of the red-brown shade. ZnPP and final heme favored the red color of matured hams, although a high concentration of these pigments increased in particular the red-violet perception.

Impact of innovative rearing strategies for the Italian heavy pigs: Technological traits and chemical composition of dry-cured hams

To explore the influence of 4 feeding strategies on dry-cured ham quality, 336 barrows and gilts (3 batches, 112 pigs/batch) of 90 kg body weight (BW), were divided into 4 groups and housed in 8 pens with automated feeders. In the control group (C), the pigs were fed restrictively medium-protein feeds and slaughtered at 170 kg BW (SW) and 265 d of slaughter age (SA). With the older age (OA) treatment, the pigs were restrictively fed low protein feeds and slaughtered at 170 kg SW and 278 d SA. The other two groups were fed ad libitum high protein feeds, the younger age (YA) group was slaughtered at 170 kg SW and 237 d SA, the greater weight (GW) at 265 d of SA and 194 kg SW. The hams were dry-cured and seasoned for 607 d, weighed before and after seasoning and deboning. Sixty hams were sampled and sliced. The lean and the fat tissues were separated and analyzed for proximate composition and fatty acid profile. The model of analysis considered sex and treatment as fixed factors. With respect to C: i) OA lowered the ham weight, the lean protein content, increased marbling and decreased the PUFA proportion in intramuscular and subcutaneous fat; ii) YA hams had thicker fat cover with lower PUFA in intramuscular and subcutaneous fat; iii) GW increased the deboned ham weight, fat cover depth and marbling, reduced PUFA in intramuscular and subcutaneous fat, without alteration of the lean moisture content. Sex had a negligible impact.

Application of a non-invasive tool and identification of genetic markers in swine to enhance ham quality: a preliminary study

A genome-wide association study (GWAS) was performed as a preliminary step to identify regions potentially related to ham quality traits. In this research, genomic information was obtained from 238 commercial hybrid pigs utilising the GeneSeek® Genomic Profiler genome-wide porcine genotyping array. Carcasses were tested for hot weight, the thickness of backfat and loin, and lean meat percentage. The corresponding fresh hams were assayed for weight and ultimate pH; the activities of Cathepsin B and Ferrochelatase of Semimembranosus muscle were determined through fluorimetric methods. The lean meat percentage of fresh ham (LMPH), salt absorbed after first (SALT1) and overall salting stages (SALT) were estimated online by the Ham Inspector™ apparatus. Hams were processed in compliance with the procedures established for Protected Designation of Origin Parma ham, and ham weight losses were measured at the main processing stages. Hot carcass weights showed a significant negative correlation with their lean meat percentage and LMPH, while LMPH was correlated positively with carcass lean meat, SALT1, SALT, and weight losses. The GWAS detected genome-wide association for 12 single nucleotide polymorphisms with Ferrochelatase activity. The results obtained in this preliminary study were achieved by combining innovative and non-destructive technologies for screening hams under processing, measures of enzymatic muscle properties relevant to dry-cured ham quality, and genomic information obtained through a GWAS. Additional studies carried out in a larger number of pigs have been planned to investigate the effect of gene variants of Ferrochelatase activity in the dry-cured ham's quality with main reference to colour development and to confirm the GWAS results obtained in this study.

Modifying the Quality of Pig Carcasses, Meat, and Dry Fermented Sausage from Black Slavonian Pigs by Selecting the Final Body Weight and Nutrition

A total of 96 Black Slavonian pigs were subjected to the research, in which they were split into 6 groups. Three groups (100, 120, and 130 kg) were fed a higher level (HL) of crude protein in fodder mixtures (CPFM), and three groups (100, 120, and 130 kg) were fed a lower level (LL) of CPFM. After the pigs were slaughtered, pig carcasses were dissected and the meat and halves quality indicators were determined. According to the influence of the final body weight (BW) and nutrition of pigs on the quality of their halves, meat, and dry fermented sausages (kulens), it was concluded that feeding an HL of CPFM increased the proportion of loin, belly rib part, and chin and increased the muscle tissue in the ham, loin, shoulder, neck, and belly rib parts. However, the chemical composition of the meat and the sensory properties of the kulen were not significantly affected by feeding the pigs an HL of CPFM. It was concluded that, by selecting the final BW and adjusting the feeding strategies for pigs, it is possible to modify the conformation and composition of pig carcasses and the quality of meat and kulens produced from the Black Slavonian pig, which is important because consumers prefer products with certain characteristics and of a standard quality and are ready to pay for them.

Review: Pork quality attributes from farm to fork. Part II. Processed pork products

Pork is often consumed in a very wide variety of products, processed from integral cuts or minced meat using different conservation methods (curing, smoking, cooking, drying, fermenting). Quality of pork products results from a combination between the properties of the raw material and the processing conditions to elaborate the final products. The influence of primary production factors, slaughtering and carcass processing on the quality of fresh pork has been reviewed (part 1), considering quality as an integrative combination of various attributes: commercial, organoleptic, nutritional, technological, convenience, and societal image, the latter denotes cultural, ethical (including animal welfare) and environment dimensions related to the way pork is produced, processed, and its geographical origin. This review (part 2) focuses on the influence of primary production factors and processing techniques on the quality of two important and economically significant processed pork products issued from contrasting processing techniques: cooked ham and dry-cured ham. As with fresh pork, many factors influence the quality of processed products, and one factor can affect several attributes. Moreover, in the case of processed products, numerous factors in both animal production and processing steps interact to determine their quality attributes. The quality of cooked ham depends on the properties of the raw material (in particular pH, colour, water holding capacity, presence of destructured meat defect, etc.) which are determined by pig husbandry practices (especially the genotype), pre-, postslaughter and processing conditions including the composition of curing mixture (ingredients, additives), salting, mixing and heat treatment. Processing techniques of cooked ham aim at homogenising the product quality within a given quality category (e.g. 'standard' or 'superior') or brand. Therefore, the variability of raw material is problematic for the cooked ham processing industry, which generally seeks uniformity and homogeneity of fresh hams. Likewise, pig husbandry conditions exert even greater impact on dry-cured ham quality. Indeed, the properties of raw material (including weight of fresh ham, fat thickness, pH, intramuscular fat and antioxidants content, fatty acid profile, etc.) that result from combined effects of primary production factors (genotype, feeding, production system, etc.) interact with processing conditions (salting, drying, ripening conditions and duration, etc.) to elaborate the quality attributes of the final products. Synergies can be sought between the primary production factors and processing techniques leading to specific organoleptic characteristics (texture, taste, aroma, flavour, etc.) that can be valued by quality labels. Quality of products is thus built along the whole chain from farm to fork.

Describing backfat and Semimembranosus muscle fatty acid variability in heavy pigs: Analysis of non-genetic factors

This study aimed to describe the multivariate structure of Semimembranosus muscle and backfat fatty acid (FA) composition in 798 Italian Large White heavy pigs and to investigate the effects of environmental factors and carcass characteristics on FA variations. The total FA variability in muscle and backfat was characterized by a negative correlation between saturated and polyunsaturated FAs, which strongly depended on the carcass adiposity. Slaughtering season was also relevant, with pigs slaughtered in autumn having more n-6 FAs and eicosadienoic acid in backfat, while pigs slaughtered in winter displayed more saturated FAs. Regarding Semimembranosus muscle, pigs with heavier belly cuts and slaughtered in autumn had higher proportions of cis-vaccenic and palmitoleic acids, while those slaughtered in summer had more saturated FAs. Slaughtering season emerged as a relevant factor shaping both backfat and muscle FA composition, indicating that more studies and attention should be paid to environmental factors, which may have effects on FA metabolism and deposition in finishing pigs.

Finishing season and feeding resources influence the quality of products from extensive-system Gascon pigs. Part 2: muscle traits and sensory quality of dry-cured ham

The quality of pork products from local breeds in extensive systems depends, among other things, on pig production. In particular, the variability in climatic conditions and feeding resources may influence the properties of tissues at slaughter and the quality of pork and processed products. The present study (part 2) was part of a larger project that assessed the influence of the finishing season and feeding resources on carcass and tissue traits and the quality of meat and dry-cured ham from Gascon pigs in an extensive system. Following the specifications of the Protected Designation of Origin "Noir de Bigorre", castrated Gascon males were reared on rangelands (grassland and forest areas) and received a supplementary diet from 5 to 6 months of age until slaughter at a minimum of 12 months and ca. 170 kg BW. Three finishing seasons were considered: Winter (n = 18), Spring (n = 22) and Autumn (n = 23). To estimate the specific effects of season on quality traits and avoid bias due to effects of genes known to influence these traits, polymorphisms in the RYR1, PRKAG3, MC4R and LEPR genes were included in the analysis models. Compared to Winter pigs, Spring and Autumn pigs had higher ultimate pH in the semimembranosus and gluteus medius (GM) muscles, lower meat lightness (P < 0.05) and tended to have higher GM intramuscular fat (IMF) content (P < 0.10). They also had higher GM contents of saturated, monounsaturated and polyunsaturated fatty acids (FAs) than Winter pigs (P < 0.05). Spring pigs had the lowest n-6:n-3 polyunsaturated FA ratio and the highest GM α-tocopherol content (P < 0.001), indicating pig grazing. The finishing season did not influence the processing yield of dry-cured hams (24-month process). Within each seasonal group, ten hams selected for genetic variability and IMF content were analyzed by a trained sensory panel. The season did not modify the appearance or odor, but influenced texture and taste. Hams from Winter and Spring pigs had higher tenderness and melting fat scores than hams from Autumn pigs (P < 0.01). Hams from Spring pigs had higher taste intensity and salty taste (P < 0.01) but lower positive tastes (e.g. fruits, forest) than hams from the other groups. Overall, finishing season had moderate effects on ham sensory traits. Furthermore, our results reveal high redness, tenderness, taste and odor intensity, and low rancid flavor of hams from Gascon pigs produced in an extensive system.

The effects of curing agents on the proteolysis and lipid oxidation of pastırma produced by the traditional method

In the study, the effects of nitrate and/or nitrite (150 mg/kg KNO₃, 300 mg/kg KNO₃, 150 mg/kg NaNO₂, and 150 mg/kg KNO₃ + 150 mg/kg NaNO₂) on proteolytic changes (free amino acid composition, SDS-PAGE) in pastırma were investigated. Pastırma samples were also analyzed in terms of some qualitative (pH, a_w, TBARS, residual nitrite, salt) properties. The lowest total free amino acid content (1818.3 mg/ 100 g DM) was observed in the combination of 150 mg/kg KNO₃ + 150 mg/kg NaNO₂, while the highest content (2847.49 mg/ 100 g DM) was observed in 150 mg/kg KNO₃. Although the pastırma groups generally exhibited similar SDS-PAGE profiles, differences were detected at some band intensities. The lowest TBARS value (22.24 μmol MDA/kg) was observed in 150 mg/kg KNO₃ + 150 mg/kg NaNO₂. As a result, the use of 150 mg/kg KNO₃ in the pastırma curing process causes more intense proteolysis.

The effect of salting time and sex on chemical and textural properties of dry cured ham

Effect of reduced salting and pig sex on the quality of Slovenian dry-cured ham Kraški pršut was studied. A total of 48 hams from 24 crossbred pigs (12 gilts, 12 castrates) were submitted to two different salting regimes; standard salting for 18 days (HS hams, n = 24) and shortened salting (LS hams, n = 24) for 10 days. Reduced salting time effectively reduced salt content but resulted also in higher extent of proteolysis of LS hams which was associated with differences in texture and colour of biceps femoris muscle. Lower fat oxidative stability was observed in HS hams. With regard to sex effect, the hams originating from gilts were more proteolysed which was associated with differences in texture and colour. Lipid oxidation was similar in gilts and castrates.

Differentiation of dry-cured hams from different processing methods by means of volatile compounds, physico-chemical and sensory analysis

The aim of this study was to characterize dry-cured hams from four different processing methods (differences in primary leg treatment, salting and smoking phase). Volatile compounds were isolated by using headspace-solid phase microextraction and analysed by gas chromatography/mass spectrometry (GC/MS). Samples were also evaluated by sensory and physico-chemical characteristics (moisture, protein, fat and NaCl content, a_w, colour). 149 volatile compounds of dry-cured hams were identified and 15 of them were quantified. Identified volatile compounds belonged to several classes of chemical: 25 aldehydes, 18 phenols, 12 alcohols, 16 terpenes, 27 aromatic hydrocarbons, 18 aliphatic hydrocarbons, 17 ketones, 9 esters and 7 acids. Most abundant volatiles in ham samples were aldehydes (34.46-49.78%). Principal component analysis showed a good separation among groups. Smoked dry-cured hams showed a higher content of phenols, aromatic hydrocarbons, and acids and were characterized by smoky aroma, while non-smoked dry-cured hams showed higher content of terpenes, ketones, alcohols, esters, aliphatic hydrocarbons and were characterized with spicy aroma.

Effects of single nucleotide polymorphisms and haplotypes of the protein kinase AMP-activated non-catalytic subunit gamma 3 (PRKAG3) gene on production, meat quality and carcass traits in Italian Large White pigs

PRKAG3 is a major gene for meat quality and production in pigs. In this study, we investigated two single nucleotide polymorphisms (SNPs) of the PRKAG3 promoter region (g.-995A>G and g.-311A>G) in 381 pigs of different breeds. Association between these SNPs and three major haplotypes, constructed including other three substitutions (c.89C>A, c.154A>G and c.595G>A) and different traits (meat quality parameters: pH_2h, pH_u, glycogen and lactate content, glycolytic potential and cathepsin B activity of Semimembranosus muscle; estimated breeding values and random residuals for growth performances and carcass traits) were analysed in 271 Italian Large White performance tested pigs. A significant effect (P=0.043) of the g.-995A>G SNP on cathepsin B activity and a suggestive effect (P=0.067) of the g.-311A>G SNP on pH_u were found. The haplotype [g.-995G:g.-311G:c.89A:c.154G:c.595G] was associated with pH_u (P=0.024), glycolytic potential (P=0.040) and cathepsin B activity (P=0.086). This study on haplotypes, including promoter region SNPs, contribute to explain the effect of this gene on meat quality traits in pigs.

Growth parameters, behavior, and meat and ham quality of heavy pigs subjected to photoperiods of different duration

To attain a good level of animal welfare, pigs require a sufficient environmental illumination. Therefore, minimum levels for light duration and light intensity have been set up by the European legislation (Directive 2008/120). An experimental trial was designed to determine whether an increased duration of the photophase (up to 16 h of light per day) could modify the behavior, productive parameters, and meat and ham quality of Italian heavy pigs. Forty crossbred (Large White × Landrace) castrated males pigs (26 kg initial average BW) intended for Protected Designation of Origin (according to European Union Regulation 1151/2012, ) dry-cured ham production were raised according to Parma ham production rules up to the weight of 160 kg. Pigs were homogeneously allotted to 2 experimental groups, each comprising 20 pigs. The short photoperiod (SP) group received the minimum mandatory number of hours of light per day (corresponding to 8 h/d), whereas the long photoperiod (LP) group was subjected 16 h of light per day during the whole production cycle. Light intensity was maintained at 40 lux (i.e., the minimum mandatory level) for both the experimental groups. Growth and slaughtering parameters, carcass traits, fatty acid composition, meat and dry-cured ham quality, and animal behavior were assessed. Pigs in the LP group showed a greater live weight and carcass weight compared to the SP group ( = 0.005 and = 0.007, respectively). Similarly, hams obtained from the LP group were significantly heavier and their weight losses during the dry-curing period were reduced ( < 0.01) when compared to the SP group. No significant differences were detected between the experimental groups as concerns meat and ham quality or fatty acid composition of the subcutaneous fat. Pigs in the LP group spent more time resting and less time pseudo-rooting ( < 0.01). Our results indicate that, given an appropriate dark period for animal rest, an increased duration of the photoperiod, even at the lower mandatory light intensity level, can favorably affect growth parameters of heavy pigs without any negative effect on animal behavior, carcass traits, or meat or long-cured ham quality. Therefore, rearing pigs in semidarkness should be considered as a baseless practice, contrary to animal welfare.

Enhancement of physicochemical, microbiological and sensory properties of dry-cured loin by using processed sulfur-fed pigs

The present study showed that processed sulfur supplementation and processing condition affected changes in physicochemical, microbial and sensory properties of dry-cured loin. The pigs were divided into two groups at the fattening phase: non-sulfur-fed pigs (NSFP) and 0.3% processed sulfur-fed pigs (SFP) in fattening phase. The crude fat content of SFP was lower than that of NSFP in raw meat and dry-cured loin. Lipid and pigment oxidation were suppressed in SFP compared with NSFP during whole process. Lightness of SFP was significantly higher than that of NSFP during storage. SFP showed higher colour stability than did NSFP during storage. Moreover, microbial spoilage of dry-cured loin was greatly prevented in SFP compared with NSFP. Free amino acids related to taste in SFP were significantly higher than those in NSFP. Polyunsaturated fatty acid of dry-cured loin from SFP group was higher than that of NSFP, while saturated fatty acid of NSFP was significantly higher than that of SFP. SFP had higher preference and flavour scores than did NSFP in a sensory test. Feeding processed sulfur improved the meat-quality characteristics and extended the shelf-life of meat products.

Factors in pig production that impact the quality of dry-cured ham: a review

This study reviews the factors of pig production that impact the quality of dry-cured ham. When processing is standardized, the quality of the final dry-cured product is primarily determined by the quality of the meat before curing (green ham). This has been defined as the aptitude for seasoning and is determined by the green ham weight, adipose tissue quantity and quality, meat physico-chemical properties and the absence of visual defects. Various ante-mortem factors including pig age and weight, genetic type, diet, feeding strategy and slaughter conditions determine green ham properties such as the dynamics of water loss, salt intake and, as a consequence, proteolysis and lipolysis. Muscle conditions (pH, salt concentration, water content and availability, temperature) influence enzymatic activity and development of characteristic texture and flavor. Generally, hams of older and heavier pigs present better seasoning aptitude because of higher adiposity. Adiposity is also positively correlated with fat saturation, which is desired to avoid rancidity and oiliness. The fatty acid profile of tissue lipids can be manipulated by diet composition. Feeding strategy affects tissue accretion and protein turnover, thus directly impacting proteolysis. With respect to the impact of pig genotype on dry-cured ham quality, local breeds are generally considered more suitable for producing quality dry hams; however, the majority of dry-cured hams on the market today are from modern pig breeds raised in conventional systems, providing lean hams. The importance of all these factors of pig production is discussed and synthesized, with an emphasis on the main difficulties encountered in dry-cured ham production.

Carcass and ham quality characteristics of heavy pigs from different genetic groups intended for the production of dry-cured hams

Carcass and ham quality characteristics of pig populations divided by harvest weights--HW (130 and 160 kg) were evaluated to determine the effects of gender (barrows and gilts) and distinct genetic groups--purebred (DUDU) and crossbred Duroc (DULA, DUWI and DULL) as well as purebred Large White (WIWI) on the suitability for use in dry-cured ham production. At 130kg, DUDU pigs yielded the highest fat thickness of the ham (P<0.01) and an intramuscular fat content (IMF) of 3.15% in Semimembranosus muscle (SM). DUDU pigs also had a SM pH(u) of 5.7. This genetic group met the specifications for dry-cured ham production. No differences could be found in meat quality characteristics between genetic groups harvested at 160 kg. However at this HW, gilts produced significantly (P<0.05) heavier and leaner hams compared to barrows.

Single nucleotide polymorphisms in several porcine cathepsin genes are associated with growth, carcass, and production traits in Italian Large White pigs

To identify DNA markers associated with performance, carcass, and meat production traits including muscle postmortem cathepsin activity, several porcine genes encoding for lysosomal proteinases (cathepsin B, CTSB; cathepsin D, CTSD; cathepsin F, CTSF; cathepsin H, CTSH; cathepsin L, CTSL; and cathepsin Z, CTSZ) and for a cathepsin inhibitor (cystatin B) were investigated. Single nucleotide polymorphisms were identified in CTSD, CTSH, CTSL, and CTSZ genes with a combination of in silico expressed sequence tag database mining and single-strand conformation polymorphism analysis. Sequencing and PCR-RFLP protocols were used to validate the identified polymorphisms. Allele frequencies at these loci were investigated in Italian Large White, Landrace, Duroc, Piétrain, Belgian Landrace, Hampshire, and Meishan breeds. Genotyping CTSD and CTSH markers made it possible to genetically map these genes to SSC 2 and 7, respectively. Markers in CTSD, CTSH, CTSL, and CTSZ genes, together with mutations we previously reported in cystatin B, CTSB, and CTSF genes, were genotyped in an Italian Large White sib-tested population (272 or 482 animals). For these animals, meat quality traits (cathepsin B activity, pH measured at 2 h postmortem, pH measured at 24 h postmortem, glycogen, lactate, and glycolytic potential of semimembranosus muscle) and EBV for ADG, lean cuts (LC), backfat thickness (BFT), ham weight (HW), and feed:gain ratio (FGR) were determined. Analyzed markers did not show any association with muscle cathepsin B activity. Thus, it could be possible that different genes, other than these investigated candidates, affect this trait, which is correlated with the excessive softness defect of dry-cured hams. The results of association analysis confirmed the effects we already reported in another study for CTSF on ADG (P = 0.008), LC (P = 0.001), and BFT (P = 0.02). Moreover, CTSD was associated with ADG, LC (P < 0.0001), BFT, HW, and FGR (P < 0.001); CTSH was associated with FGR (P = 0.026); and CTSZ was associated with ADG (P = 0.006), LC (P = 0.01), HW (P = 0.024), and FGR (P = 0.029). The biochemical and physiological functions of the lysosomal proteinases, together with the results obtained in our investigation, suggest that the cathepsin gene family might play important roles affecting economic traits in pigs.

Effect of extended aging of parma dry-cured ham on the content of oligopeptides and free amino acids

The effect of the dry-curing processing time on the release of oligopeptides and amino acids was evaluated with 158 Parma hams subdivided into three groups: (1) traditional processing (450 days); (2) extended processing (570 days); and (3) extended aging (690 days). Most of the oligopeptides and free amino acids detected increased up to the last deadline (690 days); a sharp increase of peptides below 400 Da was the main change in most aged hams. In particular, gamma-glutamyl dipeptides showed a remarkable increase during ham extended aging, acting like permanent taste-active compounds, being unsuitable for further enzymatic breakdown. The pH of fresh hams showed negative relationships (P < 0.001) with most peptides. With regard to free amino acids, the pattern was modified by different processing lengths, together with their taste categories, so that the amino acids having monosodium glutamate-like and bitter tastes were enhanced in more aged hams.

Computer image analysis for measuring lean and fatty areas in cross-sectioned dry-cured hams

The aims of this study were 1) to apply computer image analysis to obtain measures of lean and fatty areas on the cross section of dry-cured hams, 2) to investigate variation of these measures, and 3) to evaluate reproducibility and repeatability of these techniques. Traits of concern were the cross-sectional area (SA), lean, or muscles, area (LA), and the fatty area (FA) centered on the cross section and surrounded by biceps femoris, semimembranosus, semitendinosus, and quadriceps femoris, as well as the FA-to-SA ratio (FESR). Hams were obtained from crossbred pigs (n = 279) slaughtered at 9 mo of age (mean BW of 169 +/- 17 kg). Digital images of the cross section of dry-cured hams were captured using standardized procedures. Three replicated measures of areas were collected by three operators using three image analysis techniques (automatic, automatic-assisted, and manual). Variance components were estimated using a linear model that included slaughter group, gender, and gender x slaughter group as fixed effects and operators, pig, and operator x pig as random effects. Statistical analyses considered all measures (n = 7,533) or measures collected after reinstruction of all operators for spatial calibration of the analysis system (n = 4,428). Average SA, LA, FA, and FESR were 350 cm2, 220 cm2, 8.7 cm2, and 2.5%, respectively. Variability of FA (CV = 42%) and of FESR (CV = 39%) was four times greater than that of SA and LA. Slaughter group, pig, operator, and operator x pig effects were the most (P < 0.01) important sources of variation of measures. Correlations between measures obtained with different techniques were greater (P < 0.01) than 0.90, with the exception of LA measures. Coefficients of reproducibility for SA and LA ranged from 87 to 94%, whereas those for FA and FESR ranged from 88 to 98%. Coefficients of repeatability ranged from 92 to 99%. Automatic-assisted and manual methods provided more reproducible and repeatable measures than the automatic technique. Spatial calibration of the software system was a key issue affecting reproducibility and repeatability. Reinstructing the analysts for spatial calibration enhanced both reproducibility and repeatability of all methods of analysis. Computer image analysis is a technique suitable for measuring lean and fatty areas in cross-sectioned hams, providing reproducible and repeatable measures, and it might be used in large sample-based studies to investigate causes of defective fatty areas.