This study aimed to evaluate the quality of the longissimus lumborum muscle in PLW × PL pigs fed diets supplemented with a probiotic, a prebiotic and a synbiotic. The study material comprised the longissimus lumborum (LL) muscle sampled from fattening pigs. The animals were fed complete feed rations according to the following scheme: control group (I) – no feed additives; group II – 0.3% EM Bokashi; group III – 3% inulin; and group IV – 0.3% EM Bokashi + 3% inulin. The pigs were fattened until they reached an average body weight of approximately 112 kg. The inclusion of feed additives in the diets did no affect carcass muscularity or fatness (p > 0.05). Supplementation with inulin and EM Bokashi (group IV) significantly reduced muscle pH at 45 min and 2 h post-mortem compared to group II. No significant effect of the feeding strategy was observed on the electrical conductivity, water holding capacity or the LL muscle tenderness. However, the highest drip loss and muscle tenderness were recorded in pigs fed diets supplemented with inulin. The muscles from pigs in groups I and II were darker in colour (L*), but less saturated in red and yellow hues than the LL muscle from pigs in groups III and IV (p ≤ 0.05). A significantly higher intramuscular fat (IMF) content (1.73% and 1.67%) was recorded in the muscles of pigs fed diets with EM Bokashi or inulin, respectively, compared to the control group (1.28%). Simultaneously, the LL muscle from pigs receiving the prebiotic-supplemented diet contained significantly less cholesterol than that from groups II and IV. The higher IMF levels in the LL muscle of pigs fed inulin or EM Bokashi contributed to a significantly (p ≤ 0.05) increased content of oleic, saturated, and monounsaturated fatty acids compared to that of control pigs. Based on these findings, the inclusion of 3% inulin in complete feed rations for fattening pigs is recommended, as it resulted in the lowest cholesterol level and most favourable fatty acid profile in the longissimus lumborum muscle.

The aim of this study was to assess the impact of drip loss (DL) from the Longissimus lumborum (LL) muscle tissue on the quality characteristics of fresh and packaged culinary pork meat derived from fattening pigs from a large-scale production system. The research was conducted during the spring–summer season on a sample of 120 fattening pigs. The animals were raised and handled pre-slaughter under uniform conditions. Slaughter and post-slaughter procedures were carried out in accordance with the standard protocols of the meat processing plant. The analysed material was standardized in terms of hot carcass weight (85.27 4.06 kg) and lean meat content (57.02 3.76%).The considerable variation in DL from the LL muscle tissue at 48 hours post mortem enabled the formation of four experimental groups differentiated by this parameter: Group I ≤ 2.0%, Group II from 2.01% to 4.0%, Group III from 4.01% to 6.0% and Group IV > 6.0%, which constituted the research factor in this study. The packaging system effectively reduced storage losses in both MAP- and VAC-packaged meat, regardless of the DL group at 48 h post mortem. DL from the LL muscle was significantly associated with the intensity of glycolytic changes, as expressed by pH value at 45 minutes post mortem and throughout the whole storage period from 24 to 144 hours post-slaughter. The obtained results indicate the potential use of DL as a determinant for meat selection in accordance with its intended use in the meat industry (culinary meat vs. processing meat).

This study aimed at identifying genomic regions that affect nine pork quality traits in purebred and crossbred fatteners. A total of 259 fatteners represented bysix purebreds/crosses were genotyped for 45556 SNP markers by Illumina Porcine SNP60 BeadChip. The following traits were recorded: glycogen potential (GP), glycogen content (GC), lactate content (LC), pH(35), pH(24), pH(48), drip loss after 48 hours (DL48), color lightness (L*) and lean meat content (LMC). Multi-Locus Mixed Model methodology was applied to find associations between SNPmarkersand recorded traits. Several SNPs were found to besignificantlyassociated with some pork quality traits: four SNPs (located on SSC7, SSC10and SSC14) with GP, three SNPs (SSC10, SSC14) with GC, one SNP (SSC15) with DL(48)and one SNP with pH(48). Genetic variation explained by significant SNPs ranged from 7.6% to 9.1%. Moreover, some genes (e.g. CAPN10, ALDH5A1, PASK, SNITA1 and MYH7B)located in the close vicinity to significant markers are proposed to becandidate genes explaining the genetic background of the traits studied

The present work aimed to estimate the usefulness and effectiveness of selected physicochemical indicators in the evaluation of meat quality as well as culinary and processing value using a simple and canonical phenotypic correlation method. Studies were carried out in 495 porkers. The most relationships were obtained for the adenosine triphosphate (ATP) breakdown indicator (R1), electrical conductivity (EC) and glycolytic potential (GP) with meat quality traits that are non-diagnostic criteria, i.e., lipids and protein content, water holding capacity (WHC), technological yield (TY), drip loss (DL) and meat tenderness (MT). The results of this study indicate that about 62% of the variability in meat quality is the result of the initial level of glycogen in muscle tissue. The strong relationship between EC2 and pH24 (acidity of the muscle tissue at 24 h after slaughter) parameters and a wide spectrum of traits of meat quality (sets covering the parameters of the culinary and processing quality of meat and indicating the volume of drip loss), as well as with the pH1 and R1 criteria confirms the possibility to perform a quick and cheap 'on line' classification of qualitative meat properties in meat processing plants.

The current study analysed the combined results of independent research and experiments to quantify the differences between organic and non-organic pork in composition and selected meat quality traits, using a meta-analytical approach. Data from 25 publications with 42 individual experiments were combined using a random-effect model to estimate the effect of organic production on composition of pork (water, protein, intramuscular fat content and fatty acids composition) and selected meat quality traits including initial in 45 min. post-mortem and the ultimate pH, drip loss, colour lightness -L*, redness - a* and yellowness - b* and Warner-Bratzler share force. The overall meta-analysis indicated that organic pork had significantly higher IMF content, lower total saturated fatty acid (SFA) and stearic acid (C18:0) concentrations, higher total polyunsaturated fatty acid (PUFA), n-3 PUFA and n-6 PUFA concentrations and higher yellowness (b*) in comparison with meat from conventional, non-organic production. In sub-groups, trend to increase in total PUFA, n-3 PUFA and n-6 PUFA has been detected in pork from high performing breeds, and from pigs reared indoors. From traditional breeds, organic pork had significantly lower total SFA, C16:0 and C18:0 fatty acids concentrations, but didn’t differ in IMF and PUFA concentrations in comparison to conventional meat. Furthermore, organic pork loins from traditional breeds were more red and yellow than those from non-organic, conventional production. However, these benefits in redness may be diminished by application of indoor rearing.

Stunning is a statutory pre-slaughter process that may affect the quality of pork. The objective of this study was quantification of the effects of stunning (ES vs. CO2 stunning) on selected quality attributes of pork, using a meta-analytical approach. Data from 18 publications with 46 individual experiments were combined using a random-effect model to estimate the effect size of stunning on the initial and ultimate pH (pH1, pHu); drip loss (DL); colour (lightness—L*, redness—a*, yellowness—b*); and tenderness (expressed as Warner–Bratzler shear force, WBSF) of pork. In overall, loins from ES showed significantly lower pH1 (by 0.08 units); greater DL (by 0.68 p.p.); higher L* (by 1.29 units); and a* (by 0.80 units) as they compared to those from CO2 stunning. In subgroups, a greater-than-overall negative change in pH1, pHu, DL, L* and a* was detected with the application of the head-to-back (HB) stunning method. Additionally, alterations in DL and L* may be magnified with the application of conventional chilling (Conv.) to ES pigs. There was no effect of stunning on WBSF but, due to a low number of research in the database, the reliability of these results may be misleading. These results provide evidence that the differences between these two stunning methods in DL and L* may be diminished by the application of the head-only (HO) or head-to-body (HBO) method, followed by the fast chilling of carcasses.

ABSTRACT: The objective of this study was the comparative analysis of selected attributes of nutritional and technological quality of pork from Naïma and DanBred gilts mated with P-76 boars. The research was carried on 50 pigs (25 in each group) reared under the same environmental conditions and slaughtered at about 115±5.0 kg. Both analyzed crossbreds populations were characterized by overall good nutritional and technological quality. However the loins from DanBred×P-76 compared with those from Naïma×P-76 had significantly greater glycogen and less lactate concentration in early post mortem period, higher pH at all measurement points (besides no statistical differences in pH measured 2 hours post mortem), lower thermal drip and drip loss measured 96 and 144 hours post mortem and lower lightness (except no differences measured 48 hours post mortem). Additionally loins from DanBred×P-76 contained more protein and less water. No statistical differences in IMF content between both analysed groups were noted (their average values were below 2%). Aforementioned may suggest that crossing both Naïma and DanBred hybrids with P-76 boars may not improve IMF content or increase marbling scores to the levels preferred for culinary purposes.

The aim of this study was to determine the usefulness of single and multiple electrical conductivity measurements done directly in abattoir in pork quality attributes evaluation. 82 commercial hybrid fatteners (41 barrows and 41 gilts) originated from the same breeder and reared under the same environmental conditions were slaughtered at approximately 110 kg live weight. Electrical conductivity was measured at 35 min. (EC35) and 2 (EC2), 3 (EC3) and 24 hours post mortem (EC24). Pork quality was characterised after slaughter by meat acidity (pH) measured at 35 min. and 24 hours, meat colour parameters (CIE-L*a*b* system) at 24 h, drip loss at 48 h (DL48), 96 h (DL96) and 144 h (DL144), water holding capacity (WHC) and tenderness at 48 h and 144 h expressed by shear force (N/cm2). Electrical conductivity was rather weakly correlated with pork quality traits (the highest Pearson’s r, e.g. 0.30 was noted both for EC2 and a* and DL48). Highest Cr and Cr2 values for single and multiple electrical conductivity measurements and sets of pork quality traits were noted for drip loss and water holding capacity (0.42** and 0.29 and 0.57** and 0.32 respectively) while for most of remaining sets no statistical significance were found. It could be presumed then that electrical conductivity are not useful predictor of pork quality attributes that could be performed directly in abattoirs (besides drip loss and water holding capacity to some extent). Therefore it is suggested to revise this parameter use in pork quality evaluation however further examination covering larger population of fatteners should be performed.

The aim of the research was to estimate the effect of straw-based housing on selected quality attributes of pork, using a meta-analytical approach. Meta-analysis is statistical procedure that combines the results of individual, independent studies into one common treatment effect, called the effect size. Data were extracted from 17 independent studies (20 experiments) and analysed using a random-effect model to estimate the effect of straw-based housing on the pH (initial pH at 45 min post mortem and ultimate pH), drip loss, colour (L*, a*, b*) and Warner-Bratzler shear force of pork loins. The meta-analysis of the available results showed that pigs from straw-based systems may produce pork with a faster early post-mortem pH decline (pH45), higher drip loss, and greater lightness than those reared under barren conditions with concrete (slatted) floors. A subgroup analysis showed that greater space allowance for straw-housed pigs had a greater negative effect on initial pH (pH45), drip loss, and lightness than straw housing with normal/minimal floor space requirements.

ABSTRACT: This study compared the diagnostic value of pork quality evaluation methods using different pH threshold values and time-points with muscle metabolites concentration threshold values measured 45 min. post mortem in assessment of meat with lowered drip loss. Samples of 100 longissimus dorsi (LD) (Landrace × Yorkshire) × Duroc fatteners were examined after slaughter for following parameters: muscle acidity in 35 min, 2 h, 3 h, 24 h and 48 h (pH1, pH2, pH3, pH24 and pH48), colour lightness (L*, a*, b*), meat yield after curing and thermal processing in 72 °C (technological yield), water-holding capacity (WHC) and drip loss in 48, 96 and 144 h (DL48, DL96, DL144). To verify the accuracy of analysed methods two groups were distinguished according to DL48, e.g. Low DL (DL48≤4%) and High DL (DL48>4%). In High DL pH1 to pH48 were statistically lower while L*, WHC, DL48, DL96, DL144 were statistically higher (P≤0.05). On the basis of pH-dependent methods classification to RFN (red, firm, normal), PSE (pale, soft, exudative), DFD (dark, firm, dry) and AM (acid meat) was performed and then the percentage share of Low DL and High DL among meat classified as RFN was evaluated. Despite most samples were classified as RFN Low DL share among them did not exceed 50%. If meat sample shows metabolites concentration below threshold value and was assigned to Low DL (or was assigned to High DL above threshold value) it was regarded as correctly classified. The most promising cut-off point (correct classification of 73%) was 45 µmol both for glycogen and lactate.

Muscle metabolites greatly determine pork quality. However, precise threshold values which indicate its deterioration or improvement are not fully known. This study aimed to determine the influences of pork Longissimus lumborum (LL) glycogen and lactate concentrations measured at 45 min post mortem on pH, colour (L*a*b*) and drip loss (DL) measured during 144 hours post mortem in order to prescribe appropriate threshold values. The investigation used 30 gilts and 30 barrows being fattened for slaughter. After slaughter, the carcasses were assigned to groups based on the observed levels of glycogen and lactate: low GlyL with glycogen ≤35 μmol/g, GlyM with glycogen between 35 and 55 μmol/g, GlyH with glycogen >55 μmol/g; LacL with lactate ≤40 μmol/g and LacH with lactate >40 μmol/g. Lower muscle pH was noted up to 24 h post mortem in the LacH group compared to LacL (P ≤0.01). 24 h post mortem higher pH was found in GlyL than in GlyM and GlyH (P ≤0.01), which were similar. Similarly no statistical differences were noted between The GlyM and GlyH groups were also similar in L*, DL96 and DL144, with lower values found for GlyL (P ≤0.01). Compared to LacH, LacL had lower L*, DL48, DL96 and DL144 (P ≤0.01) and higher a* and b* values. Muscle pH, drip loss, L* and a* values were more affected by lactate concentration if the glycogen concentration ≥35 μmol/g muscle tissue. Thus, metabolite concentration may be a useful and valuable indicator of pork quality. Keywords: drip loss, glycolytic resources, pork colour, post-mortem muscle metabolism

The objective of this study was to examine the effect of accelerated chilling (AC) on selected attributes of LLWH (Landrace x Large White) x Hampshire pork with elevated glycogen stores. Investigation showed that application of accelerated chilling compared to conventional chilling reduced the temperature oflongissimusmuscle, increased ultimate pH (pH(48)), and significantly decreased lightness (L*) and yellowness (b*) of meat at 48 hrpostmortemwithout any effect on drip loss. Muscles with high (GP >= 180 mu mol/g) glycogen stores from AC treatment produced less lactate than those from CC (conventional chilling) treatment. However,longissimusmuscles exhibited low ultimate pH and elevated drip loss regardless of the type of the chilling treatments. Practical applications The investigation has shown that application of accelerated chilling (regardless of glycogen stores) has however a very limited ability to improve the quality of LLWH fatteners. The application of AC may reduce lactate production in muscles with high glycogen stores, but cannot prevent negative alterations in meat quality. Thus, the use of this treatment for pork with elevated glycogen stores seems negligible and commercially unjustified.

The aim of the study was to evaluate the frequencies of meat quality classes in pigs from the mass population. The study was carried out in the spring/summer season on 220 fatteners. The rearing and pre-slaughter handling conditions were the same for all animals. Slaughter and carcass handling were carried out according to the procedures used at the meat plant. The research material was similar in terms of hot carcass weight (85.27 ±3.06 kg) and lean meat content (58.02 ±2.76%). The results have shown that significant issues for the pork meat industry are acid meat (AM, with low suitability for processing) and exudative meat. The percentage of AM meat was as high as 25%, while 68% was exudative meat within the category of meat assessed as RFN (red, firm, normal). For accurate and detailed conclusions, studies must be conducted in fatteners of known origin (genotype).

The purpose of this study was to examine the high pressure processing (HPP) on four pork meat quality traits, for example, pH(u), DL, WBSF, and L* with meta-analytical approach. Three different sub-groups were included, for example, moderate (100-250 MPa) and high pressure (>250 MPa), low to ambient (0-20 degrees C) and medium to high (33-80 degrees C) temperature, and unaged (pre-rigor) and aged (post-rigor) meat. Meta-analysis demonstrated, that HPP treatment results in significant increase in pH(u) by 0.18 units, regardless of applied pressure. No effect of HPP on drip loss was observed. The greatest effect on tenderness was obtained when muscles were pressurized at moderate to high temperatures (1.04 kg in WBSF reduction). Significant increase in longissimus dorsi lightness (17.55 units) was observed-pressurization of pork loins at medium to high temperatures resulted in an increase in lightness by 2.04 units, whereas at low to ambient temperatures the overall effect achieved was 22.59. Practical applications The study shown, that high pressure processing (HPP) has an ability to prevent pH declines without a negative effect on drip loss and improves tenderness of fresh pork meat with a minimum negative effect on the color. The best results were achieved when fresh pork loins were pressurized at medium pressures (100-250 MPa). Due to raising demands of consumers toward meat quality, HPP has a potential to become a remarkable technology in pork meat industry. Its application could notably improve the efficiency of production and the resources use, which could eventually translate to lower financial losses.

The aim of this study was to compare the diagnostic values of two methods in pork meat quality evaluation, that is, Method I: pH(1) and pH(24) and Method II: electrical conductivity (EC2) and pH(24), which included pH(24), and their modifications, that is, Method III: pH(1) and pH(48) and Method IV: EC2 and pH(48), which included pH(48) measurement. Five meat quality classes, namely reddish-pink, firm and non-exudative (RFN), high quality (HQ), pale, soft and exudative (PSE), dark, firm and dry (DFD) and acid meat (AM) were assessed in four even-numbered genetic groups of 40 fatteners each, namely (LxY)xD-A, (LxY)xD-B, (LxY)xH and (LxY)x(DxP). The change of diagnostic method and therefore pH time measurement from 24 hours to 48 hours post mortem caused a major increase in the percentage of acid meat (AM) that was diagnosed. Most differences were observed in (LxY)xH fatteners, namely 77.5% between Methods I and III and 75% between Methods II and IV. This increase in AM frequency indicates that as a result of significant changes in the post-mortem metabolism that occur in the meat ageing process pH(48) should be regarded as ultimate pH (pH(u)).

The objective of this study was to examine the effect of accelerated chilling on ultimate pH (pH(u)), drip loss, color (L*a*b*), and Warner-Bratzler shear force (WBSF) of fresh pork using a meta-analytical approach. Additionally, two subgroups differentiated by stunning method (electrical vs. CO2) were included. The meta-analysis shown that accelerated chilling has an ability to improve quality of fresh pork, however, not all benefits were obviously evident. The overall effects with no overlapping zero CI provide that accelerated chilling can increase ultimate pH and prevent negative alterations in drip loss and color of pork with the evidence of heterogeneity (except pHu). Moreover, CO2 stunning favors fast chilling in development of fresh pork but undesired changes in lightness, redness, and yellowness may occur as well as relatively low shear force increase (probably not detectable by average consumer). Also, fast chilling followed by CO2 stunning has no effect on drip loss. Practical applications The study demonstrated, that accelerated chilling regime has an ability to improve quality of fresh pork, due to increase in ultimate pH and prevention of negative changes in drip loss and color. Additionally, it has been stated, that use of CO2 stunning favors accelerated chilling, however, undesired changes in lightness, redness, yellowness, and shear force may occur. The abovementioned results could provide possibility of chilling processes optimization, which should benefits development of high quality fresh pork in meat industry.

The aim of the study was to determine the usefulness of criteria (pH, R1 and EC) used to determine pork quality classes ���N, P�E, ��� and AM� in assessin� culinary �alue characteristics of pork. The study was carried out on 320 fatteners from the mass population in the sprin�-autumn season. �earin� conditions, pre-slau�hter handlin� and carcass handlin� were the same for all animals. The fatteners were similar in terms of hot carcass wei�ht �87.09 ±4.05 k�� and lean meat content �56.68 ±3.01%�. The statistically si�nificant correlations found confirmed that basic pork quality criteria are suitable for assessment of selected parameters of culinary �alue that are important to the consumer. To obtain more precise conclusions re�ardin� the suitability of basic pork quality criteria �pH1, pH24, pH48, R1, EC2 and EC24� for estimation of characteristics of culinary �alue, canonical analysis should be used to determine the relationships between two sets of �ariables: independent �basic criteria of pork quality classes) and dependent (basic culinary values of pork).

The aim of the study was to evaluate the culinary and technological value of meat obtained from three-way cross fattening pigs, i.e. [Landrace (L) x Yorkshire (Y)] x Duroc (D) and [Landrace (L) x Yorkshire (Y)] x Hampshire (H). The study was carried out in spring and summer on 60 pigs divided in 2 genetic groups: (LxY) x D and (LxY) x H. The rearing and pre- and post-slaughter conditions were the same for all animals. Slaughter and post-slaughter handling of the carcasses was in accordance with the procedure in use at the meat plant. The research material was similar in terms of hot carcass weight (85.14 ±2.90 kg and 85.31 ±3.29 kg) and lean meat content (56.50 ±2.71% and 56.98 ±1.99%) within each genetic group, i.e. (LxY) x D and (LxY) x H. The significant, highly unfavourable means obtained for meat quality traits in the case of the (LxY) x H pigs, in terms of both culinary and technological suitability for processing, clearly indicates that the Hampshire breed should not be used as a paternal component in mass production of fatteners. In the case of the (LxY) x D fatteners, the highly favourable values for meat quality traits, of importance to both the consumer and the meat industry, clearly support the use of the Duroc breed as a paternal component.