Pale, Soft, Exudative Research Articles

Microbiological growth in normal and PSE pork stored under refrigeration

The study was conducted to evaluate the microbiological development in PSE pork compared with normal meat and the effect of season of the year on the rate of proliferation of the same. Longissimus dorsi muscle samples from carcasses classified as PSE slaughter (pH45 <5.8) and normal (pH45 > 5.8) were collected after 24 hours of refrigeration, at the time of deboning, in a commercial slaughterhouse, with service federal inspection, located in the Grande Dourados region (MS). The samples (12 normal and 12 PSE) were collected at two different times of the year (fall and winter) for analysis of total and 45ºC coliforms, mesophylls, psychotropic, pseudomonas, yeasts and molds at 0, 5, 10 and 15 days of storage under refrigeration. Microbial growth behaved similarly between the two types of meat throughout the storage period, except for the count of mesophilic aerobic microorganisms, whose development was superior in PSE meat until the 5th day storage, matching between both types of meat later. Was no effect of season on the count of total coliforms and 45ºC, and their proliferation rate higher in meat from the slaughtered animals the warmer season (autumn).

Temperature induced denaturation of myosin: Evidence of structural alterations of myosin subfragment-1

Denaturation of myofibrillar proteins in porcine longissimus thoracis et lumborum muscle was investigated after pre-rigor temperature incubation at 20, 30 and 40°C. At 24h myofibrils were isolated and myosin was further cleaved by chymotrypsin. High temperature pre-rigor induced release of myosin S1 (subfragment-1), less (P < 0.05) Ca2+-ATPase activity and structural alterations of the region of the myosin molecule that harbors S1. Surface hydrophobicity of myofibrils from the 40°C group increased (P<0.001), suggesting a temperature-induced structural rearrangement exposing hydrophobic groups on the surface of myofibrils which in turn may explain the reduced water-holding of PSE meat.

Divergent selection for muscle color in broilers

One consumer-related physiological abnormality that is a recent concern for the poultry industry is atypical meat quality. Currently in the processing plant, meat is characterized on appearance such as tears, bruises, discoloration, or missing parts. Unfortunately, this method ignores physical properties such as palatability, texture, tenderness, taste, color, pH, and water-holding capacity (WHC). The growing demand for a convenient, economical, and palatable product has shifted the market toward value-added poultry products. The effect of a meat's physical properties on its marketability and versatility has become apparent to processors attempting to utilize poor quality meat. After 8 generations of divergent selection for muscle color or lightness (L*) in broilers, muscle quality parameters were investigated. The 2 broiler lines divergently selected for high (HMC) and low (LMC) muscle color along with their randombred control line (RBC) were included in the study. Heritability estimates for L* were 0.47 ± 0.05 and 0.51 ± 0.05 in the HMC and LMC lines, respectively. For generation 8, the mean L* for the HMC, RBC, and LMC lines were 53.91, 49.70, and 46.86, respectively. Selection for increased L* was found to result in increased breast fillet yellowness (b*), whereas selection for decreased L* resulted in an increase in breast fillet redness (a*). Selection for increased L* has resulted in increased rate of pH decline over time, whereas selection for decreased L* has resulted in a decreased rate of pH decline. The HMC line exhibited a higher percentage fillet drip loss than both the LMC and RBC lines, which did not differ from each other. Overall selection for L* was effective in modifying breast muscle color as well as correlated responses associated with atypical poultry meat such as drip loss and postmortem muscle pH. These selected lines can serve as resource populations for the study of PSE and DFD-like meat in poultry and demonstrate that L* selection could be applied to primary breeding programs as a way to improve or manage muscle quality in pedigree elite lines.

The effect of season of transportation on the welfare of broilers and selected parameters of broiler meat quality

During breeding, especially during transportation from the farm to the slaughterhouse, poultry is exposed to various stressful factors that influence post-mortem muscle metabolism and, consequently, the meat quality. The aim of this study was to investigate the effect of season of transportation on broiler welfare and broiler meat quality parameters: pH, colour and cooking loss t. For the purpose of the experiment, during the summer (July) and winter (November), twelve broilers were tested, reared on the same farm and belonged to the same flock of line hybrid Ross 308. Distance from the farm to the slaughterhouse was 130 km, and transport lasted 3 to 5 hours. Average values of temperature and relative humidity during transport in summer period were 20.60ºC and 65.64%, respectively, and in the winter period 14.42ºC and 69.14%, respectively. It was established that the samples of breast muscle and drumstick muscles of broiler chickens transported in summer had higher average L*(lightness) values. When the L*value of 56L* units, as the limit of PSE (pale, soft, exudative) meat, are applied on the results of the present study, it can be concluded that, in the summer, the share of pale meat in samples of breast and drumsticks was 75%, while in winter it was 33.34% for breasts and 16.67% for drumsticks. After transport, in the summer, pH values of breast and drumstick muscles (5.40 ± 0.20 and 5.71 ± 0.30, respectively) were significantly lower than the pH values measured after transport in winter (5.90 ± 0.18 and 6.46 ± 0.25, respectively). Lower values of cooking loss in the samples of breast muscle and drumstick samples (29.06 ± 2.80 and 29.69 ± 3.47, respectively) were found in broiler chickens transported in November, when exposed to lower temperatures. Between pH and cooking loss, and pH and L*values of samples of breast muscles and drumstick muscles studied after transport in summer and winter periods, negative correlation was determined.

Broiler chicken PSE (Pale, Soft, Exudative) meat and water release during chicken carcass thawing and brazilian legislation

The objective of this work was to investigate the relationship between poultry PSE meat and water loss of frozen chicken carcass in two experiments. The first experiment was carried out in commercial abattoir. Poultry carcass were classified as PSE meat (n=59) (pH 5.8). Water absorption and drip test were performed according to the Brazilian legislation methodologies. The second experiment was carried out with commercial whole five brands frozen carcasses purchased from the local supermarkets (n=30) and analyzed for pH, water holding capacity (WHC) and drip test. PSE poultry meats absorbed 3.59% of water during the processing similar to the control samples; however, released 0.38% more water during thawing of the carcasses. From these five brands evaluated, three presented drip values above 6.0%. The highest drip value was showed by the brand sample that had pH and WHC values characteristics of PSE meat. It could be postulated that PSE meat phenomenon promoted more water release during thawing leading to a misinterpretation in relation to the Brazilian legislation for water carcass liberation during thawing.

POSSIBILITIES OF THE USE OF ELECTROLYZED WATER IN POULTRY BREEDING

Abstract the paper deals with verification of the effects of the electrolyzed NaCl-water solution where a new possibility for an alternative procedure to disinfect water is provided. The experiment was done in two chicken breeding halls where the solution was used to disinfect the stable premises and at the same time it was applied into the feed water. The effects of disinfection were verified directly in the stable premises at the interval of 20, 40, 60 minutes after application. Staphylococci and Streptococci and Enterococci were inactive always after 60 minutes of effect. There was significant decrease in the number of total number of microorganisms. An evaluation of the qualitative features of the produced chicken meat, focused mainly on the PSE meat disorder, was a part of the examination, too. After the research was finished, the chickens were slaughtered at the industrial slaughterhouse and samples of the meat were taken (gradually 157 pieces in total) from the individual halls and analysed. The determined share in water loss by dripping was the most significant of the monitored indicators, which could suggest a possible development of the PSE problem, however, the meat colour and the pH values did not confirmed this. The values of pH, colour and loss of water (dripping) ascertained, processed by the T-test did not confirm the hypothesis of the assumed possible differences in occurrence of critical values of these indicators in both groups observed.

Prediction of cooked ham yields parameters by pork quality measurements (pH, colour and transport loss)

800x600 Producers of pork products are increasingly focusing on fresh meat quality indicators to predict the processing quality of cooked ham. Drip loss, colour and pH, are the most important quality parameters that are used. The aim of this study was to analyse the relationship between fresh pork characteristics and cooked ham quality. A total of 160 hams were randomly taken from pig carcasses in a slaughterhouse at 24 hours post-mortem. The hams were deboned and divided into 2 muscles: the topside ( M. Semimembranosus ) and the silverside ( Biceps femoris ). The muscles were processed into cooked hams. The cooked hams were sorted into 3 groups based on the fresh meat characteristics: pH (ultimate), colour and transport loss. Averaged processing yields of the grouped hams were compared. Also individual processing yields were correlated to the fresh meat characteristics. (colour Minolta L* value, ultimate pH and transport loss). This study confirmed that PSE meat, with a low ultimate pH, had a decreased Water Holding Capacity (WHC) and increased transport loss. During the transportation period the hams from the low pH group lost more fluid than the meat from the other 2 groups with medium and higher pH. During the injection and tumbling processes the group with the low pH, higher transport loss and lighter meat colour, gained more brine than the other 2 groups. All parameters investigated (pH, colour and transport loss) showed that, after the cooking process, the low pH and higher transport loss group was unable to retain the free water (brine solution) resulting in significantly higher cooking losses compared with the other meat quality groups. The final gain of the cooked hams was significant different only for different transport loss groups. The study concluded that pH and transport loss parameters investigated can be used to select raw material for cooked ham process under commercial conditions. The selected hams (with the higher pH or lower transport loss) had a 2.3% higher cooking yield. Normal 0 21 false false false NL X-NONE X-NONE

Commercial preslaughter blue light ambience for controlling broiler stress and meat qualities

The objective of this work was to study the effect of blue light diffuser on the broiler stress control by measuring the occurrence of PSE meat just before slaughtering. Birds were divided into the following two groups before slaughter at the point of being hung on shackles: broiler group under low intensity blue light ambience (475, 17-20 lx) and control group under white light (550-650nm, 321-332 lx). Birds' stressful conditions were measured by the occurrence of PSE meat. Breast fillets were classified as PSE meat based on pH ( 53.0). The fillet samples in the control group had the following characteristics: pHu=5.77, L* = 54.26 and b*= 6.27. The fillet samples from birds under blue light ambience had the following characteristics: pHu=5.81, L* = 52.86 and b* = 5.22 (p < 0.05). These results revealed that the treatment of blue light ambience just before slaughtering contributed to the alleviation of ante mortem stress of the birds, which was observed by a 14% decrease in the occurrence of PSE meat. Exposure to blue light just before slaughtering was shown to have potential to be used in modern slaughterhouses to offer a comfortable atmosphere, thereby maintaining breast meat quality.

Differential gene expression between normal and pale, soft, and exudative turkey meat

In response to high consumer demand, turkeys have been intensively selected for rapid growth rate and breast muscle mass and conformation. The success in breeding selection has coincided with an increasing incidence of pale, soft, and exudative (PSE) meat defect, especially in response to heat stress. We hypothesized that the underlying mechanism responsible for the development of PSE meat arises from differences in expression of several critical genes. The objective of this study was to determine differential gene expression between normal and PSE turkey meat using a 6K turkey skeletal muscle long oligonucleotide microarray. Breast meat samples were collected from Randombred Control Line 2 turkeys at 22 wk of age, and classified as normal or PSE primarily based on marinade uptake (high = normal, low = PSE). Total RNA was isolated from meat samples with the highest (normal, n = 6) and the lowest (PSE, n = 6) marinade uptake. Microarray data confirmation was conducted using quantitative real-time PCR. Selection of differentially expressed genes for pathway analysis was performed using a combination of fold change (FC) ranking (FC < -1.66, FC >1.66) and false discovery rate (<0.35) as criteria. The calcium signaling pathway was highlighted as the top canonical pathway associated with differential gene expression between normal and PSE turkey. Dramatic downregulation of fast-twitch myosin heavy chain coupled with upregulation of slow-twitch myosin and troponin C suggested a switch of skeletal muscle isoforms, which may alter muscle fiber arrangement and formation of actin-myosin complexes. Changes in expression of genes in the actin cytoskeleton signaling pathway also suggest altered structures of actin filaments that may affect cell motility as well as strength and flexibility of muscle cells. Substantial downregulation of pyruvate dehydrogenase kinase, isozyme 4 was observed in PSE samples, suggesting altered regulation of the aerobic metabolic pathway in the birds that developed PSE meat defect.

Effects of transportation time, distance, stocking density, temperature and lairage time on incidences of pale soft exudative (PSE) and the physico-chemical characteristics of pork

The study determined the effects of transportation time, distance, stocking density, temperature and lairage time on incidences of PSE and pork quality. Frequencies of PSE cases in stocking density categories within transport duration classes were determined. General linear models, regression and the principal component (PC) analysis were used to analyse the data. Highest incidences of PSE were recorded in autumn season while lowest incidences were recorded in the spring season. Transportation time and stocking density significantly affected pHu and ultimately PSE incidences although there were no interactive effects. Highest risks of PSE occurrence were observed with more space allowance. The highest incidences of PSE were observed for animals that had travelled for two hours while the PSE cases were lower in animals that travelled for longer times. Distance travelled and transportation time had significant effects (P<0.05) on thawing loss (TL) % of pork. No relationships were reported between the other pre-slaughter variables and pork quality attributes. With the exception of transportation time and distance travelled which had a positive relationship with TL%, variation in other pre-slaughter variables did not affect meat quality variables. The risks of PSE occurrence were dependent on stocking density and transportation time.

Atividades de creatina quinase e lactato desidrogenase na identificação de frangos com estresse e filés PSE (pale, soft, exudative)

Porcine Stress Syndrome (PSS) is a syndrome that occurs in pigs. PSS animals are sensitive to the anesthetic halothane, have higher activities of Creatine Kinase (CK) and Lactate Dehydrogenase (LDH) and are predisposed to the development of PSE (Pale, Soft, Exudative) meat, compromising the meat quality. In chickens, little is known about the relationship between sensitivity to and halothane changes in the activities of these enzymes with the occurrence of PSE meat. The aim of this study was to evaluate the CK and LDH activities in sensitive and non-sensitive halothane chickens and for stress susceptibility identification and PSE meat development. Birds were exposed to halothane at a 3.0 % concentration in pure O2 for 5 min. Afterwords, they were classified into groups: sensitive to halothane (HAL +) (stiffening of the lower limbs) and Non-sensitive (HAL-) (no hardening). After 3 h and 48 h to the test, blood was collected from the wing vein gill, serum extracted and stored at –22 °C until analysis of CK and LDH. No differences were observed (p ? 0.05) in CK activity for HAL+ and HAL- groups. However, differences (p ? 0.05) were observed the LDH activity at 3 h and 48 h, and 44.2 % and 66.1 % higher for the group HAL +, respectively. The determination of lactate dehydrogenase activity indicates to be an alternative to identify animals susceptible to stress thus prone to produce PSE meat.

Skeletal muscle calcium channel ryanodine and the development of pale, soft, and exudative meat in poultry

The development of pale, soft, and exudative (PSE) breast fillet meat has become an economic burden for the poultry industry worldwide. PSE meat results in 1.0-1.5% loss in moisture and carcass weight, and a 2010 estimate of the Brazilian annual production put the economic loss due to PSE at over US$30 million. In the USA, PSE has caused an annual loss of up to US$200 million to the poultry industries. The underlying causes of the color abnormality in PSE meat are not fully understood. However, the likely physiological origin of PSE broiler meat is an excessive release of Ca(2+) promoted by a genetic mutation of the ryanodine receptor (RYR), a Ca(2+)-channel protein in the skeletal muscle sarcoplasmic reticulum. In pigs, the genetic cause of PSE meat has been identified as a point mutation in the RYR1 gene at nucleotide 1843, which causes an amino acid substitution (Arg615 to Cys615) in the RYR. This mutation leads to an alteration in Ca(2+) homeostasis, hypermetabolism, intense muscle contraction, and malignant hyperthermia in pigs susceptible to porcine stress syndrome. An understanding of this process represents the basis for breeding strategies aimed at eliminating the RYR1 mutation from global pig populations, a strategy that the poultry industry intends to emulate. The aim of this study was to review the subject, with an emphasis on the most recent developments in the field.

Vplyv transportu, doby odpočinku a teploty na kvalitu bravčového mäsa z rôznych krajín

The aim of the experiment was to assess the pig meat quality in relation to preslaughter conditions and import country. In the experiment, the meat quality of 1980 pigs was evaluated. The animals were divided into three groups according to country of import (Slovakia, Hungary and Netherlands). The following pre-slaughter indicators were evaluated: duration of transport, duration of housing, temperature during housing and transport. The meat quality was judged on the basis of the pH1 value measured 45 minutes after the slaughter in the musculus longissimus dorsi – pH1 MLD and in the musculus semimembranosus – pH1 MSM. The highest frequency of PSE (pale, soft, exudative) meat in the MLD was in the group of pigs imported from Slovakia (24.13 %). These pigs had also statistically significant (P<0.01) the lowest average pH1 MLD (6.05) in comparison with other imports. The incidence of PSE meat in the MSM was in all evaluated groups above 10 %. Group of pigs from Slovakia had the lowest value of pH1 MSM (6.23) in comparison with other groups of pigs (P<0.01). Even though the average length of housing in a slaughterhouse was from 11.26 to 15.43 hours high incidence of PSE meat was recorded. However group of pigs with the longest rest period (15.43 hours - Netherlands) had significantly higher pH1 MLD and pH1 MSM compared to other imports (P<0.01). From these results can be concluded that the incidence of PSE meat in evaluated groups is relatively high. Prolonging rest period and lower temperatures had positively influence on the incidence of PSE meat and pH value.

Atividades de fosfolipase A2 secretada e glutationa peroxidase em filés PSE (pale, soft, exudative) de frango

The excessive release of calcium from the sarcoplasmic reticulum during the installation of PSE (Pale, Soft, Exudative) meat, leads to increase of phospholipase A2 (PLA2) activity and consequently causes a higher lipid oxidation. In contrast, glutathione peroxidase (GSH-Px) is a selenium-dependent antioxidant enzyme that prevents the oxidative damage. The aim of this work was to investigate the secreted PLA2 (sPLA2) and GSH-PX activities in PSE poultry meat. Breast meat samples ( Pectoralis major m. ) (n=24) were obtained from commercial slaughterhouse. Samples were classified as PSE and Control Meat based on pH and L* values, fillets with pH1h30? 6.0 and L24h* ?53.0 as PSE and fillets with pH1h30> 6.0 and L24h* 0,05). The GSH-Px activity was approximately 24,4% higher (p?0,05) for Control meat when compared to PSE meat. The sPLA2 activity of PSE fillets did not changed, however PSE fillets present the enzymatic system of antioxidant defense compromised with lower GSH-PX activity.

Atividades de fosfolipase A2 secretada e glutationa peroxidase em filés PSE (pale, soft, exudative) de frango

The excessive release of calcium from the sarcoplasmic reticulum during the installation of PSE (Pale, Soft, Exudative) meat, leads to increase of phospholipase A2 (PLA2) activity and consequently causes a higher lipid oxidation. In contrast, glutathione peroxidase (GSH-Px) is a selenium-dependent antioxidant enzyme that prevents the oxidative damage. The aim of this work was to investigate the secreted PLA2 (sPLA2) and GSH-PX activities in PSE poultry meat. Breast meat samples (Pectoralis major m.) (n=24) were obtained from commercial slaughterhouse. Samples were classified as PSE and Control Meat based on pH and L* values, fillets with pH1h30? 6.0 and L24h* ?53.0 as PSE and fillets with pH1h30&gt; 6.0 and L24h*&lt;53.0 with Control. sPLA2 was analyzed using enzymatic assay kit and GSH-Px was measured a coupled assay procedure recording the NADPH (nicotinamide adenine dinucleotide phosphate reduced) oxidation. The sPLA2 average was 0.295 Umg-1 of protein for PSE meat and 0.380 Umg-1 of protein for Control meat, did not differ significantly (p &gt;0,05). The GSH-Px activity was approximately 24,4% higher (p?0,05) for Control meat when compared to PSE meat. The sPLA2 activity of PSE fillets did not changed, however PSE fillets present the enzymatic system of antioxidant defense compromised with lower GSH-PX activity.

Propriedades físicas e sensoriais da carne suína PSE

Objetivou-se avaliar as características físicas e sensoriais da carne suína PSE, suas correlações e os prejuízos causados para a indústria, em função de sua ocorrência. Em abatedouro comercial aferiu-se o pH das carcaças (n=1601) aos 45 minutos post mortem (pH45), classificou-as em PSE (pH45&lt;5,8) ou normais (pH45≥5,8). Após 24 horas de resfriamento, foram coletadas amostras do músculo Longissimus dorsi de 26 carcaças PSE e 26 normais, que foram avaliadas quanto à coloração (L*, a*, b*), perda de exsudato, perda de peso por cozimento, força de cisalhamento, atributos sensoriais (maciez, suculência e palatabilidade) e composição centesimal. Foram avaliadas as correlações entre parâmetros físicos e sensoriais. A incidência de carnes PSE foi de 10,06%. O pH final, perda de peso por cozimento, força de cisalhamento e composição centesimal não diferiram entre os tipos de carne. A perda de exsudato foi, aproximadamente, 39% maior para carne PSE. O pH45 correlacionou-se, negativamente, com L* (R= -0,331) e b* (R= -0,528). A suculência correlacionou-se, positivamente, com a palatabilidade (R= 0,436) e maciez (R= 0,297) e, negativamente, com a perda de peso por cozimento (R= -0,326). A força de cisalhamento apresentou correlação positiva com perda de exsudato (R= 0,529) e negativa com maciez (R= -0,767). O prejuízo estimado em função da ocorrência de carnes PSE foi da ordem de R$340.800,00 anuais. Carnes PSE apresentam alterações negativas nas propriedades funcionais e sensoriais, relacionadas com a redução de sua capacidade de retenção de água, o que causa perdas consideráveis para a indústria processadora.

Consumer attitudes and preferences regarding pale, soft, and exudative broiler breast meat

SUMMARY The objective of this work was to assess the perceptions of Brazilian consumers regarding the color and drip loss of fresh pale, soft, and exudative (PSE) broiler breast fillet meat at the point of sale and subsequently in cooked samples, and to assess its acceptance by panelists. The abnormal fillet samples (PSE meat) were characterized by pH 5.61 and a lightness (L*) value of 59.26, compared with control samples with pH 5.96 and an L* value of 49.24, respectively (P ≤ 0.05). In addition, the water-holding capacity of control samples was 14.50% higher, cooking loss was 30.92% lower, and shear force was 65.41% lower than those values in the PSE samples. The PSE samples were identified by consumers as paler, and consumers preferred the control samples. Among the attributes of cooked samples, such as tenderness, flavor, and juiciness, only flavor was significantly different (P ≤ 0.05), and control samples had higher consumer acceptance values (P ≤ 0.05).

Technological and sensory pork quality in relation to muscle and drip loss protein profiles

Fifteen meat samples collected from pigs (Neckar hybrid line) were selected from 75 animals on the basis of their technological quality traits, and the samples were classified as normal, PSE, and acid meat. Sensory analysis was performed on the three meat categories. Total meat protein and drip loss protein were analyzed by electrophoresis (SDS-PAGE), mass spectrometry, and image analysis. From a sensory point of view, PSE meat was characterized by lower color intensity, and acid meat was characterized by the lowest score of juiciness. Certain soluble proteins derived from the drip loss were associated with meat quality, especially phosphoglucomutase and the B chain of hemoglobin in the case of PSE and acid meat. Low quantities of myofibrillar proteins (myosin LC1, troponin T (TnT) and troponin C (TnC)) in meat with high glycogen levels and low pH levels resulted in a higher rate of proteolysis of myofibrillar proteins due to higher enzymatic proteolysis activity in the meat. The results of this study showed that the TnC/TnI ratio may be a pertinent marker of postmortem muscle metabolism and that this ratio is related to textural properties.

EFFECTS OF pH VALUES AND FAT CONTENT ON SODIUM CHLORIDE DIFFUSION RATE IN PORK

Chloride diffusion was studied in pale, soft, exudative (PSE) pork meat of pH 5.4 to 5.5, normal-quality meat of pH 5.6 to 5.7 and dark, firm, dry (DFD) meat of pH 6.6 to 6.8, as well as in meat-fat batters of 10, 20 and 30% of fat. Cylindrical glass pipes filled with meat or batter were immersed into brine containing 16% NaCl and 0.16% NaNO2. After 24, 48, 72, 96, 120, 144 and 168 h of curing, chloride content in samples was measured and effective diffusion coefficient (Def) was calculated. Along with the decrease of pH of meat, sodium chloride content increased and higher Def was noted. Chloride concentration in the internal layer of PSE meat was about 80% higher compared with the normal-quality meat and about 130% higher than in DFD meat. Chloride Def decreased significantly with the increase of fat content in meat-fat batter. PRACTICAL APPLICATIONS Besides technological benefits of curing process in meat, excessive residues of the reacting curing ingredients can lead to the direct toxicological effects. Thus, there is a need to optimize the curing process in the direction to determine a precise dosage of the curing substances and appropriate time of curing which depends on the chemical composition of raw material as well as its biochemical condition. The results obtained in the study enabled to adjust the curing time of meat of different pH and fat content. Meat of lower pH should be cured shorter than normal-quality meat, whereas dark, firm, dry meat (high pH) should be cured longer. Fat content in raw meat also significantly affects the salt migration rate. With increase of fat content, the time of curing should be longer. The described findings might be helpful in designing the technological process.

Lightness of the color measured by computer image analysis as a factor for assessing the quality of pork meat

The aim of this study was an attempt to use computer image analysis (CIA) to detect PSE (pale, soft, exudative) defect in pork meat. Material for the study was 50 slices obtained from pork longissimus muscles (m. longissimus) from 50 different animals. Based on measurements of pH, electrical conductivity, color lightness (L*), sixteen of the slices were classified as PSE meat. Another sixteen slices showed features of a normal meat. Photos of tested meat slices were taken and analyzed with computer image analysis. The article presents the data in three color models: RGB, HSV/HSB and HSL. Obtained results demonstrate the possibility of using V/B values (HSV/HSB model), L (HSL model) and the R, G, B values with the RGB model to detect PSE defect in pork meat.