Dariusz Lisiak

A new simple method for estimating the pork carcass mass of primal cuts and lean meat content of the carcass

The aim of this study was to develop regression equations for estimating lean meat content and the mass of primal cuts (ham, loin, shoulder, belly) based on selected linear measurements. The experiment involved a classification of 141 pigs from the Polish commercial pig population, with hot carcass weight ranging between 60 and 120 kg. The study population was characterised by high variability in terms of analysed measurements. Eight measurements were made including: mass of half-carcass, backfat thickness at different points (over shoulder, over last rib, over the middle of M. gluteus medius), width and thickness of the M. longissimus dorsi measured over the last rib, thickness of the lumbar and the gluteal muscle layer located between the spinal cord and beginning of the M. gluteus medius and waist width – the width of the carcass measured at the narrowest point of the lumbar. A subjective five-point scale was used to score difficulties in obtaining linear measurements (workload rate). The lean meat percentage and mass of cuts were determined by dissection. The study enabled equations to be devised for estimating lean meat content with an accuracy greater than most devices used for carcass classification (estimation error 1.67). Regression coefficients for the mass of primal cuts were: 0.92 for ham, 0.87 for loin, 0.87 for shoulder, and 0.74 for belly. The error of equations used to estimate the mass of primal cuts were: 391 g for ham, 447 g for loin, 263 g for shoulder and 257 g for belly. The workload rate for all the developed regression equations ranged from 1.3 to 1.6 points. The outcome of this study was the development of equations to predict carcass value without the need to use expensive classification equipment.

The estimation of pork carcass primal cuts value based on backfat thickness

The aim of the present study was to determine the effect of pork carcass backfat thickness on the dissection efficiency of four primal cuts (ham, loin, shoulder, belly), including correlation coefficients. The research material consisted of 80 pork carcasses. Backfat thickness (mm) was measured on cold half-carcasses using a vernier caliper at 6 points: at the first cervical vertebra (atlas), over shoulder at the thickest point, on the back, at the beginning, center, end of the gluteus medius muscle (CI, CII, CIII). On the basis of the average backfat thickness, measurements from 6 points were separated into two experimental groups: I (<25 mm); II (≥25 mm). Detailed dissection of the elements was performed to define mass (g): total, intermuscular fat, bones and lean meat. The significant effect of fat thickness on intermuscular fat content regardless of the cut was noted. Correlations between the average backfat thickness of 6 points and the total weight of the four main elements were calculated. In addition, the correlation coefficients were compared between the dissection elements and the average backfat thickness of 6 and 5 points. Higher backfat thickness determined the increase in the total mass of loin, shoulder and belly. A statistically proven correlation was shown between the average backfat thickness and the total mass of the analysed elements (r=0.293). When comparing the correlation coefficients of a different number of measurements a specific tendency was observed. Positive correlation coefficients were slightly higher for an average of 5 points of backfat thickness and negative correlation coefficients were slightly higher for an average of 6 points. Statistical differences between groups were recorded at the same level for the same parameters (P≤0.001 and 0.01

Development of ZP Method for Seurop Pig Carcass Grading in Poland

Abstract In the present study, ZP method for lean meat content (LMC) evaluation in pig carcasses was tested. The experiment was carried out on 141 pigs selected from animals delivered for slaughter to the SKIBA S.A. meat plant located in Chojnice. The selected pigs originated from three country regions, and differed in respect of subcutaneous fat thickness (7-32 mm), carcass weight (60-120 kg) and sex (50% gilts and 50% castrated males). The main result of the study was a rectilinear regression equation for lean meat content assessment. Two linear measurements were used in the equation, i.e. backfat thickness measured on sacral vertebra and thickness of the muscle layer located between the beginning of the cross section of gluteus medius and back edge of the spinal cord. The evaluation error RMSEP was 2.33% and did not exceed the limit defined in EU regulations. Based on the Commission Decision 2011/506/EU the ZP method was approved to be used for pig carcass grading in Poland. A special measuring template was developed for the industrial use of the ZP method.

Methodology of data processing in the process of neural image analysis of pork half carcasses

This article describes data processing in neural analysis of the images of pork half carcass. Parameters of pork halfcarcass obtained from three-dimensional analysis, was processed into form of 130 files. These files has been used as learning sets for the artificial neural network simulator - STATISTICA. Next, we obtained the set of neural models from which the best was chosen. For all data processing activities in this research process were used applications developed in C # in the Visual Studio 2015 development environment.

Unsupervised neural classification of six chosen apple pests using learned vector quantization agorithm

The aim of this work was a neural identification of selected apple tree orchard pests in Poland. The classification was conducted on the basis of graphical information coded in the form of selected geometric characteristics of agrofags, presented on digital images. A neural classification model is presented in this paper, optimized using learning files acquired on the basis of information contained in digital photographs of pests. There has been identified 6 selected apple pests, the most commonly encountered in Polish orchards, has been addressed. In order to classify the chosen agrofags, neural networks type Self-Organizing Feature Map (SOFM) methods supported Learned Vector Quantization (LVQ) algorithm were utilized, using by digital analysis of image techniques.

Prediction of primal cuts by using an automatic ultrasonic device as a new method for estimating a pig-carcass slaughter and commercial value

The objective of the present work was to develop regression equations to estimate the percentage, weight (in g) and lean meat content (in %) of the primal cuts of a pig carcass by using Auto-Fom and to estimate the commercial value of the carcass on the slaughter line in a meat-processing plant. The research was conducted on 168 pig carcasses. From the whole pork carcass, only the most valuable cuts (i.e. belly, ham, loin, neck and shoulder) and also meat content in ham and shoulder were weighed at a 100 g accuracy and the percentage of each cut in carcass was calculated. Loin ‘eye’ height and belly-muscle thickness were also measured. The regression equations for the prediction of the primal-cut weights and their percentages in the pig carcasses were derived using the partial least-square procedure. The developed equations include 70 variables that are standard measurements taken with an Auto-Fom device. These equations have a satisfactory accuracy rate and are useful in estimating the yield of the elements, especially for loin, ham and belly content. Belly-muscle thickness (R2 = 0.98) and the percentage of meat in the ham (R2 = 0.93) can be estimated with a high precision. It was confirmed that the developed equations may be used in the current Auto-Fom software.

Novel ultrasound approach for measuring marbling in pork

An ultrasound examination was done on the m. longissimus lumborum, between the 10th and the 11th thoracic vertebra, on two sides (inside and outside the thoracic cavity) of the left half-carcasses of 162 fatteners. The carcasses were classified for lean meat percentage using the SEUROP system. The R pig carcasses (47.7% lean) had the thickest backfat (30.6mm; P≤0.01) and the highest content of intramuscular fat (IMF=2.28%; P≤0.01). More artifacts-free images were collected from the inside compared to the outside of the pig carcasses (90.1% vs. 58.6%; P≤0.01). The percent of bright pixels (PBP) was the highest for the inside, for all the lean-meat-content classes (P≤0.01). The correlation between the PBP and the IMF was higher for the images of the inside compared to the outside (r=0.811; P=0.001 vs. r=0.523; P=0.009). The ultrasound images of the inside of the carcasses proved to be the most useful for making an assessment of the marbling.

Meat quality of beef from young bull carcases varying in conformation or fatness according to the EUROP classification system

Abstract A total of 172 bull carcases were studied in order to determine a relation between m. longissimus dorsi (LD) quality and EUROP grades. The carcases were of four conformation grades and three fatness grades. The quality assessment of the m. LD was performed and based on a pH measurement, colour measured with a Minolta CR-400 and marbling estimation. Based on the available research a thesis might be forwarded that both types of carcase classification: conformation and fatness are not related with the meat quality of studied carcase grades. Only share of redness and yellowness values were lower in meat of P carcase grade as well as the lowest marbling was in meat of U carcase grade. It was also stated that bull’s hot carcase weight was higher as the better conformation class and as the higher fatness class. Similar relation in the rib-eye area of LD muscle of different conformation grades was observed.

The effect of crossing the rare Spotted Zlotnicka breed with other pig breeds on the slaughter value of the fatteners and the quality of raw maturing (dry-cured) meat products

Abstract The dry-cured necks and hams produced from the meat of Złotnicka Spotted (ZS) pigs and their crossbreds with Duroc and Polish Large White, were tested. The slaughter value of the fatteners was determined (lean meat content, backfat thickness, area of the loin cross-section). The water, fat, protein and NaCl content was established in the final products. The meat colour (L* a* b*) and pH were measured. The final products were subjected to sensory evaluation and ranked on the scale of 1-5 points. Crossing the Złotnicka Spotted with the PLW resulted in higher lean meat content by approx. 4 percentage points (p.p.) and in thinner back fat thickness by 0.6 cm. Dry-cured ham produced from the meat of different fattener groups did not differ significantly in terms of physico-chemical traits as well as sensory traits. The sensory characteristics of both ham and neck received high scores (on average above 4.5 points). It was found that the tested products differed in terms of chemical content. The dry-cured necks contained approx. 19.45% of fat in the group of the ZS × PLW crossbreds whereas in other groups this figure was 2 to 6 p.p. higher. The dry-cured ham that was produced was based on the meat of purebred pigs containing 3 to 4.6 p.p. less fat compared to the crossbreds with the Duroc. The research proved that crossing the ZS with PLW and Duroc did not make the quality of the dry-cured products deteriorate.

A computer method to analyse the impact of ultrasound frequency on the brightness of USG images of muscle cross-sections

A total number of 270 ultrasound images of m. longissimus behind the 13th thoracic vertebrae were obtained on 90 lamb carcasses. Three different scanning frequencies were used (5.0, 7.5 and 10.0 MHz) in order to analyse how the frequency of the ultrasound wave affects the changes of pixel brightness in the ultrasound image. In the images obtained with 10 MHz probe the brightness of the 1st region was higher by 27% and 25% (P≤0.01) compared to the same region of images obtained with 5 MHz and 7.5 MHz frequency probe. The 3rd region of muscle cross-sections obtained with 10 MHz frequency was very dark, with the brightness lower by 22,5% and 28,3% compared to the same region of images obtained with 5 MHz and 7.5 MHz frequency. In the images obtained with 10 MHz scanning frequency, the decrease of brightness from the 1st to the 3rd region of the image was very sharp. While in the images obtained by means of 5 and 7.5 MHz ultrasound frequency, the brightness changes between the regions were very fluent. To conclude, the results of the presented research reveal that high ultrasound frequency has a negative impact on ultrasound image brightness and may reduce the information value of the image.