Search Results (194)

This study aimed to evaluate the nutritional composition and fermentation quality of feed fermented by Bacillus amyloliquefaciens and Bacillus licheniformis as well as their effects on growth performance, meat quality, blood parameters, and gut microbiota in fattening pigs. A total of 72 healthy Duroc × Landrace × Large White crossbred barrows (68.78 ± 1.41 kg, p > 0.05 for initial body weight among groups) were randomly assigned to three dietary treatments, with four replicates pens per treatment and six pigs per pen. The pigs were fed one of three diets: (1) CK: 100% basal diet; (2) YR1: 50% basal diet + 50% feed fermented with Bacillus amyloliquefaciens YR3.2; and (3) YR2: 50% basal diet + 50% feed fermented with Bacillus licheniformis YR3.1. The experiment consisted of a 7-day adaptation period and a 50-day treatment period. The results showed that the crude protein, starch, lactic acid, acetic acid, and propionic acid contents were significantly higher in the treatment groups than in the control group (p < 0.05). The final body weight of fattening pigs, serum superoxide dismutase activity, and redness value of the longissimus dorsi muscle were significantly higher in the treatment groups than in the control group (p < 0.05). The carcass weight of the YR1 group was significantly higher than that of the other groups (p < 0.05). Moreover, the shear force of pork was significantly lower in the treatment groups than in the control group (p < 0.05). Microbial analysis showed that Firmicutes dominated the jejunum and cecum in all groups (>80%). In the YR1 group, the abundance of Clostridium increased in the jejunum, whereas the abundance of Terrisporobacter decreased. In the YR2 group, the abundances of both Clostridium and Terrisporobacter increased in the jejunum and cecum. In conclusion, fermented feed prepared with Bacillus amyloliquefaciens and Bacillus licheniformis has a positive effect on the growth performance of fattening pigs, but fermented feed prepared by Bacillus amyloliquefaciens YR3.2 has a more significant effect on improving growth performance, feed conversion efficiency and some meat quality indicators. Full article

Intramuscular fat content is a key determinant of pork quality, influencing traits such as tenderness, juiciness, and flavor. However, the molecular mechanisms regulating intramuscular fat deposition in indigenous pig breeds remain incompletely understood. This study aimed to identify genes and regulatory mechanisms associated with intramuscular fat accumulation in Hezuo pigs. Longissimus dorsi muscle samples from Hezuo pigs with extreme high and low intramuscular fat contents were subjected to chromatin accessibility profiling and transcriptome sequencing. Comparative analyses identified 2201 differentially accessible chromatin regions and 588 differentially expressed genes between the two groups. Functional enrichment analyses indicated that these genes were mainly involved in lipid metabolism, focal adhesion, extracellular matrix–receptor interaction, fatty acid metabolism, and adenosine monophosphate-activated protein kinase signaling. Integration of chromatin accessibility and gene expression datasets identified 92 co-regulated genes associated with intramuscular fat deposition, including MYLK3, PDGFC, PAK1, IGF1R, LAMA4, DIAPH1, SDC4, GADD45G, and RXRG. These findings reveal regulatory networks underlying intramuscular fat accumulation in Hezuo pigs and provide candidate genes and molecular resources for improving meat quality through genetic selection and breeding programs. Full article

Enhancing meat quality and optimizing pork-free amino acid profiles can boost the industry competitiveness of pork. Plant-extracted phenolic substances have beneficial effects on meat quality. This study evaluated the effects of dietary supplementation with hesperidin, rosmarinic acid, and their combination on meat quality in finishing pigs. Twenty-four pigs were divided into four dietary treatment groups: CON (basal diet), HES (basal diet supplemented with 600 mg/kg hesperidin), RA (basal diet supplemented with 40 mg/kg rosmarinic acid), and HES-RA (basal diet supplemented with 300 mg/kg hesperidin and 20 mg/kg rosmarinic acid). After 90 days, pigs were slaughtered and sampled following a 12 h fast. Compared with the CON group, the HES-RA group pigs exhibited a significant increase in pH45 min and meat color a*, and had a decrease in meat color L* and drip loss. The combined HES-RA supplementation significantly increased the activities of glutathione peroxidase, total antioxidant capacity, and total superoxide dismutase, while reducing malondialdehyde. Furthermore, the contents of arginine and leucine were elevated in the muscle and serum. This combination treatment also modulated the ileal microbiota composition, notably enriching short-chain fatty acid-producing genera such as Veillonella and Mitsuokella, and increased the concentrations of acetate, propionate, and butyrate in the ileum. Furthermore, the combined supplementation significantly elevated the muscle mRNA expression of GLUT4, mTOR, S6K1, and 4E-BP1. Collectively, the hesperidin and rosmarinic acid supplementation was associated with enhanced meat quality, along with improved antioxidant capacity, modulation of gut microbiota and SCFA production, and upregulation of mTOR-associated gene expression. Full article

This study investigated the effects of drying methods, namely freeze-drying and vacuum-drying, and heating plate temperature (20 °C, 40 °C, and 60 °C) on the drying kinetics, specific energy consumption, proximate chemical composition, colour, peroxide value, pH and cutting force of beef eye of round muscle, pork loin, and chicken fillet. Drying time ranged from 360 min for pork loin freeze-dried at 60 °C to 1050 min for beef eye of round muscle vacuum-dried at 20 °C, and freeze-drying was generally faster than vacuum-drying at the corresponding temperature settings. Among the tested models, the logarithmic model provided the best fit to changes in the moisture ratio, with R² values of 0.9972–0.9997 and RMSE values of 0.0053–0.0151. Increasing the drying temperature reduced the specific electrical energy consumption per kilogram of dried product in both drying methods, which was associated with shorter drying times at higher temperatures. Fat and protein contents did not differ significantly in products dried at 20 °C and 40 °C, but decreased at 60 °C, reaching 8.85–12.26 g/100 g d.m. and 76.16–79.86 g/100 g d.m., respectively. Drying also affected lipid oxidation and pH. At 20 °C and 40 °C, changes in peroxide value were moderate, whereas at 60 °C lipid oxidation markedly increased, especially in chicken meat and vacuum-dried samples. Both drying methods reduced pH compared with the raw material, with the greatest decrease observed at 60 °C, particularly after vacuum-drying. The highest L* value among dried samples was recorded for chicken fillet freeze-dried at 20 °C (85.44), whereas the lowest was observed on the surface of beef eye of round muscle vacuum-dried at 60 °C (41.98). Increasing temperature decreased lightness and redness but increased yellowness and cutting force. Cutting force ranged from 35.7 N for chicken fillet freeze-dried at 20 °C and cut across the fibres to 231.4 N for beef eye of round muscle vacuum-dried at 60 °C and cut along the fibres. These results indicate that the drying method and temperature strongly affect the quality attributes of dried meat and should be selected according to the desired product characteristics. Future studies should focus on the optimisation of drying parameters for specific meat types and include a broader quality assessment, particularly microbiological safety and sensory properties. Full article

Processed meat products represent a major challenge for proteomic species identification due to extensive thermal treatment and protein structural changes. In this study, species-specific peptides in pork, chicken, and bovine meat products were identified using a directed fragmentation-assisted de novo sequencing workflow that combines 4-formylbenzene-1,3-disulfonic acid (FBDA) peptide derivatization, dual-polarity data-independent mass spectrometry (DIA-MS), and Protein Acrobat de novo sequencing software. Comparative analysis of non-fractionated and strong cation exchange (SCX)-fractionated pork luncheon samples improved peptide and protein identification after fractionation, with 312 peptides and 115 protein groups detected exclusively in fractionated samples. Species-specific peptides were predominantly assigned to conserved muscle-related proteins, including myosin, troponin, and tropomyosin, while sequence variability enabled reliable species discrimination despite protein conservation across species. To evaluate applicability for food fraud detection, mixed meat samples containing 10% chicken in pork or bovine matrices were analyzed, reflecting potential economically motivated adulteration through substitution with lower-cost meat components. Several chicken-specific peptides remained detectable in both mixtures, demonstrating robustness of the FBDA-assisted peptide sequencing combined with SCX fractionation and DIA-MS for detection of adulteration in complex processed food matrices. These findings establish a mass spectrometry-driven orthogonal method to ELISA testing for fast, reliable and accurate metaproteome analysis of highly processed food. Full article

The application of pulsed electric fields (PEFs) as a pre-treatment in the meat industry offers significant potential for intensifying mass transfer processes. This study investigated the effect of PEF treatment at three energy levels (0.1, 0.3, and 0.5 kJ/kg) on the efficiency of osmotic dehydration of pork loin using two ternary osmotic solutions: 5% NaCl + 40% maltose syrup and 10% NaCl + 40% maltose syrup. Key physicochemical and quality parameters were analyzed, including mass change, muscle tissue shrinkage, water-holding capacity (WHC), moisture content, salt content, and color attributes. The results demonstrated that PEF pre-treatment applied before osmotic dehydration significantly improved water-holding capacity and reduced water activity in pork. Moreover, the effect of the lowest tested energy level (0.1 kJ/kg) on dehydration-related parameters depended on the osmotic solution composition and was most evident in the 10% NaCl system after 6 h of dehydration, while this treatment also limited NaCl uptake by the tissue. A noticeable decrease in lightness (L*) and a shift toward negative b* values were also observed, which may be associated with structural condensation and reduced light scattering on the meat surface. Overall, the findings confirm that PEF pre-treatment combined with ternary osmotic solutions effectively modifies the physicochemical properties of pork, enabling the production of a stable product with distinctive quality characteristics and supporting process efficiency. The obtained results constitute a valuable contribution to the existing knowledge on the combined use of PEF and osmotic dehydration, as studies addressing this integrated approach in pork have not been published to date. Full article

Improving tenderness in whole-muscle pork products remains a technological challenge, particularly when natural processing strategies are preferred over conventional additives, as texture is regarded as one of the most important quality attributes influencing consumer perception and acceptance of meat products. This study investigated whether two plant proteases, papain and bromelain, incorporated into a red algae-based brine containing Palmaria palmata could enhance the quality of injected pork loin without compromising microbiological safety or sensory acceptance. Seven batches were produced: a control sample and six enzyme-treated samples containing papain or bromelain at 0.015%, 0.030%, and 0.045%. Overall, the enzymatic treatments had a limited effect on proximate composition. However, a modest decrease in fat content was observed, from 3.09% in the control sample to 2.70–2.82% in the samples treated with the highest concentrations of papain and bromelain (0.045%). In contrast, instrumental color and texture were strongly affected. Enzyme-treated samples became lighter, less red, and less saturated, with redness decreasing from 13.07 in the control to 5.19–6.66 in the highest-dose treatments and total color differences reaching 8.66. The most relevant effect was observed in texture, where papain and bromelain markedly reduced shear force, shear work, hardness, gumminess, and chewiness; shear force decreased from 26.22 N/cm² in the control to 10.78 N/cm² and 9.38 N/cm² in the batches treated with the highest enzyme concentrations. During refrigerated storage, total viable counts increased gradually but remained low, with a maximum of 4.56 × 10² CFU/g, while Escherichia coli, Salmonella spp., and Listeria monocytogenes were not detected. Sensory analysis further showed that enzymatic treatment improved perceived tenderness and juiciness without reducing overall acceptability. These findings indicate that papain and bromelain can be used as natural tenderizing tools in injected pork loin, offering a promising route toward cleaner-label meat products with improved texture and preserved microbiological quality. Full article

This study investigated the effects of ultrasound-assisted marination on NaCl diffusion in pork using multiphysics simulation and evaluated the accuracy of electrical impedance spectroscopy for predicting NaCl content during marination. The results showed that short-term ultrasonic treatment did not significantly enhance moisture diffusion from brine into pork tissue. However, multiphysics simulation demonstrated that ultrasound significantly accelerated NaCl penetration, enabling a reduced brine concentration without compromising the final salt content, as further confirmed by thermogravimetric analysis, which showed higher residual NaCl and mass in treated samples. Electrical impedance properties exhibited systematic changes with increasing ultrasonic marination time, including decreased impedance, increased phase angle, and a reduced Cole–Cole arc radius, reflecting enhanced NaCl diffusion and structural modifications in muscle tissue. A strong linear correlation between impedance parameters and NaCl content was established, and validation results confirmed that impedance spectroscopy can accurately predict NaCl levels during marination. These findings highlight the potential of combining ultrasound-assisted marination with impedance-based techniques for real-time, non-destructive monitoring of salt content in meat processing. Full article

Pork production is closely linked to skeletal muscle growth and anabolic processes. This study investigated the effects of dietary supplementation with a multi-strain probiotic (Lactiplantibacillus plantarum, Streptococcus thermophilus, and Bacillus subtilis) on the growth performance, carcass traits, gut microbiota, and potential signaling pathways in growing pigs. A total of 144 weaning piglets (28 days old) were randomly allocated to two groups and fed diets with or without probiotics (0.1%) for 18 weeks. Pigs fed with probiotics showed significantly improved feed efficiency (p < 0.05) and greater muscle mass in the loin eye, arm shoulder, and blade shoulder regions. Microbiome analysis revealed significant enrichment of short-chain fatty acid (SCFA)-producing taxa, including Acidaminococcus, Allisonella, Dialister, and Megasphaera, alongside an increased cecal butyrate level in pigs fed probiotics. Integrated fecal microbiome and serum metabolomics analysis demonstrated that the metabolite profile was substantially altered by the supplementation of probiotics. Additionally, serum insulin levels, expression of the bile acid receptor tgr5, and upstream genes in the PI3K/Akt/mTOR pathway (igf1r, insr, and pi3k) were significantly upregulated (p < 0.05). Collectively, these results suggest that a multi-strain probiotic supplementation may be a promising strategy for improving muscle deposition and feed efficiency in commercial pig production. Full article

Consumer preferences for pork are increasingly prioritizing quality traits such as flavor and tenderness, which are often superior in Chinese indigenous pig breeds. The primary objective of this study was to explore the molecular basis of flavor traits using Rongchang (RR), Yorkshire (YY), and RR × YY (YR) breeds. The investigation focused on meat quality traits, along with untargeted metabolomics, lipidomics, and volatile flavor compound (VOC) profiling of the longissimus dorsi muscle. The results indicated that RR pork exhibited higher pH levels and overall acceptability. Analyses using electronic nose and tongue demonstrated that RR pork elicited stronger responses for W2S, W1S, and W1C sensors, as well as for umami and sourness. A total of 15 VOCs were identified as differing among the breeds. RR pork contained higher levels of benzothiazole and dimethyl sulfoxide, but lower levels of nonane, 2-methylheptane, and 2,4-dimethylheptane. Metabolomic analysis revealed 45 distinct metabolites, with a greater abundance of flavor precursors such as α-ketoglutaric acid in RR pork. Lipidomic analysis identified 22 different lipids, with triglycerides being more enriched in RR pork. Phospholipids, such as phosphatidylcholine (PC) and phosphatidylethanolamine (PE), varied by breed, with PC (e) being lowest and cardiolipin highest in RR pork. Correlation network analysis revealed that nonane, 2-methylheptane was the most connected flavor compound, positively correlating with certain lipids and metabolites, such as PC (18:1_18:1), PE (18:2e_22:6), PC (36:4) and 2-phenylglycine, and negatively correlating with PC (32:0e), SM (d41:1), N-hydroxy-2-acetamidofluorene, and histamine. This multi-omics approach provides a comprehensive view of the molecular signatures associated with pork preference, identifying potential biomarkers for meat quality that can be leveraged for future breeding strategies. Full article

This study investigated the diffusion kinetics of sodium chloride (NaCl), magnesium chloride (MgCl₂), potassium chloride (KCl), and calcium chloride (CaCl₂) during wet salting of pork samples up to equilibrium conditions. Pork rump steaks were submitted to wet salting in saturated solutions of NaCl, KCl, MgCl₂, and CaCl₂ at 1, 5, 10, and 15 °C. The empirical Peleg and Weibull models, as well as a diffusion model, were used to describe the evolution of water content (WC) and salt content (SC) throughout the process. Increasing temperature decreased WC and increased SC, as well as the diffusion coefficients of water and salts in pork samples. The Weibull model provided accurate predictions of WC and SC up to equilibrium conditions. Among the evaluated salts, faster mass transfer rates and higher diffusion coefficients were observed for KCl. In addition, CaCl₂ and MgCl₂ resulted in higher equilibrium salt content compared to NaCl and KCl, which may be attributed to their higher ionic strength and stronger interactions with muscle proteins. These findings provide useful insights for optimizing wet salting processes using alternative salts for sodium reduction. The results of this study may serve as a basis for estimating salting time when using KCl solutions, particularly under similar processing conditions. Full article

This study aimed to assess the occurrence and contamination levels of OTA in edible tissues of slaughtered pigs in Greece using high-performance liquid chromatography with fluorescence detection (HPLC-FD). Kidney, liver, muscle, and fat samples were collected from 1695 healthy slaughtered pigs originating from 113 swine farms across eight geographical regions of Greece and analyzed for OTA. OTA was not detected in muscle or fat samples. In contrast, OTA was detected in 99 of 1695 kidney samples (5.8%), with concentrations ranging from 0.36 to 1.36 μg/kg (mean 0.73 μg/kg; median 0.70 μg/kg). OTA-positive kidney samples were identified in four regions, with the highest prevalence recorded in the regional unit of Karditsa, within the region of Thessaly (75/105 samples; 71.4%), where the maximum OTA concentration in kidneys was observed (1.36 μg/kg). Karditsa was also the only regional unit where OTA was detected in liver samples (40/1695; 2.4%), with concentrations ranging from 0.42 to 1.08 μg/kg (mean 0.61 μg/kg; median 0.53 μg/kg). The lack of detectable OTA levels in muscle and fat indicates minimal consumer exposure through pork; nevertheless, the presence of low-level residues in kidneys and liver emphasizes the necessity for ongoing monitoring using sensitive analytical methods. Overall, OTA contamination in edible tissues was low and unevenly distributed, reflecting localized exposure likely associated with region- or farm-specific feed contamination. Full article

The use of olive by-products in livestock farming is a valuable resource, given their high levels of bioactive compounds with antioxidant and health-promoting properties. This preliminary study adopted an integrated approach to evaluate the influence of dietary Olea europaea L. polyphenols on animal welfare, physiological stress response, intestinal morphofunctional traits, and meat quality in Neroametà finishing pigs, a novel Casertana × Large White genetic line (Neroametà). Thirty pigs reared under extensive farming conditions were randomly allocated to two groups (n = 15): a control group fed a standard diet (C) and a treatment group (OL) supplemented with 300 mg/head/day of olive polyphenolic extract for 90 days. The study focused on the systemic correlation between host health and product quality. Meat composition, rheological properties, meat antioxidant activity, stress parameters, and fatty acid profiles of the longissimus lumborum and psoas major muscles were analyzed. Results showed that the OL diet significantly modulated the HPA axis, as evidenced by a marked reduction in plasma ACTH and cortisol levels, alongside improved antioxidant status. These physiological changes were positively associated with a trophic effect on the intestinal mucosa, characterized by increased villus height and a more favorable villus/crypt ratio. Regarding meat quality, the OL group exhibited superior oxidative stability, optimized pH decline, and an improved intramuscular fatty acid profile (increased MUFA and n-3 PUFA, reduced SFA). Despite the pilot scale of 30 animals, these findings provide a solid foundation for characterizing the Neroametà breed. In conclusion, Olea europaea L. polyphenols act as a multi-level modulator, enhancing physiological resilience and meat quality, offering a sustainable strategy for high-quality pork production in line with circular economy and One Health principles. Full article

This study investigated fresh pork and pork subjected to repeated freeze–thaw cycles. The effects of freeze–thaw treatments on water status, WHC, and quality attributes of pork were systematically analyzed, and a nondestructive prediction method for WHC based on magnetic resonance imaging (MRI) was developed. The results showed that increasing freeze–thaw cycles significantly reduced moisture content and increased drip loss, indicating a continuous deterioration of overall WHC. Texture parameters and shear force values decreased markedly, suggesting that muscle structure was progressively damaged by ice crystal formation and recrystallization. T₂-weighted MRI pseudo-color scans clearly reflected changes in internal water distribution, with high-signal regions gradually decreasing as freeze–thaw cycles increased, which was consistent with the experimentally measured trends in moisture content and WHC. Based on MRI features, principal component regression (PCR) and partial least squares regression (PLSR) models were established to predict pork WHC. The PCR model extracted 16 principal components (cumulative contribution rate of 96.394%), with calibration set results of Rc² = 0.8825 and RMSEC = 1.7959, and validation set results of Rp² = 0.8856 and RMSEP = 2.0284. The optimal number of latent variables for the PLSR model was six, yielding calibration set results of Rc² = 0.9634 and RMSEC = 1.0026, and validation set results of Rp² = 0.9656 and RMSEP = 1.1119, with all residuals less than 1. Overall, the combination of MRI and chemometric methods, particularly the PLSR model, enables rapid, nondestructive, and accurate prediction of pork WHC, providing a useful tool for quality evaluation under repeated freeze–thaw conditions and for quality control in pork processing, storage, and cold-chain management. Full article

In recent years, with changes in dietary structure, beef has become the third most consumed meat in China after pork and chicken, with its consumption increasing by approximately 50%. The quality and commercial value of beef vary considerably across different muscles. However, due to the high similarity in the appearance of beef cuts and strong background interference, traditional image features are often insufficient for accurate classification. In this study, an improved convolutional neural network based on YOLOv11 was proposed. Four beef muscles were categorized: sirloin (longissimus dorsi), fillet/tenderloin (psoas major), oyster blade (infraspinatus), and ribeye (longissimus thoracis). A dataset comprising 3598 images was established to support model training and validation. We divided the dataset into training, testing, and validation sets in a 6:2:2 ratio. To enhance model performance, wavelet convolution (WTConv) was employed to effectively expand the receptive field and improve image understanding, while a large separable kernel attention (LSKA) module was introduced to strengthen local feature representation and reduce background interference. Comparative experiments were conducted with other deep learning models as well as ablation tests to validate the proposed model’s effectiveness. Experimental results demonstrated that the proposed model achieved a classification accuracy of 98.50%, with Macro-Precision and Macro-Recall reaching 97.38% and 97.38%, respectively, and a detection speed of 147.66 FPS. These findings confirm the potential of the YOLOv11n-cls model for accurate beef classification and its practical application in intelligent meat recognition and processing within the Chinese beef industry. Full article