The application of biosensors for drip loss analysis and glycolytic potential evaluation

Dietary Taurine Supplementation Improves the Meat Quality, Muscle Fiber Type, and Mitochondrial Function of Finishing Pigs

This study investigated the effects of dietary supplementation with taurine (TAU) on the meat quality, muscle fiber type, and mitochondrial function of finishing pigs. The results demonstrated that TAU significantly increased the a* value while decreasing b*45 min, L*24 h, and drip loss24 h and drip loss48 h in the longissimus dorsi (LD) muscle. Dietary supplemented with TAU reduced the content of lactate and the glycolytic potential (GP) in the LD muscle. Dietary supplemented with TAU enhanced the oxidative fiber-related gene expression as well as increased succinic dehydrogenase and malate dehydrogenase activities while reducing lactate dehydrogenase activity. Furthermore, dietary supplementation with TAU increased the contents of mtDNA and ATP and mitochondrial function-related gene expression. Moreover, TAU enhanced the mRNA expressions of calcineurin (CaN) and nuclear factor of activated T cells c1 (NFATc1) and protein expressions of CNA and NFATc1. The results indicate that dietary TAU supplementation improves meat quality and mitochondrial biogenesis and function and promotes muscle fiber-type conversion from the glycolytic fiber to the oxidative fiber via the CaN/NFATc1 pathway.

Fungal Biostarter Effect on the Quality of Dry-Aged Beef

Meat aging is a process consisting of its storage in specific conditions which leads to an increase in its organoleptic qualities. The most common method of meat aging is the wet vacuum-bag based method, whereas the traditional method, called dry-aging, involves keeping meat at a low temperature for an extended time. However, this process is characterized by low repeatability of the results. Therefore, different approaches to stabilize the process are tested. The aim of this study was to analyze the influence of the Mucor flavus biostarter on the physicochemical characteristics and sensory quality of dry-aged beef (DAB). We hypothesized that a fungal biostarter positively influences the quality of DAB and stabilizes the dry-aging process. Meat control samples (N = 7) and samples inoculated with the Mucor flavus biostarter (N = 7), originating from 14 individuals crossbred from Holstein-Friesian cows with bulls of meat breeds, were put into the dry-aging fridge (DryAger, Bad Saulgau, Germany) for 28 days. The physicochemical parameters (pH, color parameters, WHC, GP (glycolytic potential), chemical composition of muscle, the content of malondialdehyde, shear force), muscular protein proteolysis (SDS-PAGE), sensory quality, and microbial composition of DAB were assessed after aging. The results showed a significant effect of the fungal biostarter on pH increase (0.25 units), and light myosin chain proteolysis (approximately 16%) as well as improvement of sensory quality (e.g., acceptability was improved by one unit in an applied scale 1-9). All together, the M. flavus-based biostarter was shown to increase the quality of DAB.

Comparison of meat quality and glycolysis potential of two hybrid pigs in three-way hybrid model

With the improvement of consumers' requirements for pork quality, the method of crossbreeding with excellent local pig breeds to improve meat quality is popular. Saba pig has high reproduction rate, good meat quality and high utilization rate of roughage, but its excellent characteristics have not been fully developed and utilized. To promote the development and utilization of Saba pigs and production of high-quality pork, the meat quality traits and glycolysis potential of Duroc × (Landrace × Yorkshire) (DLY), Berkshire × (Duroc × Saba) (BDS), and Duroc × (Berkshire × Saba) (DBS) three-way crossbred pigs were compared. The results showed that DLY had the highest live weight, carcass weight, lean meat percentage, drip loss, glycolysis potential, muscle diameter, and relative mRNA expression levels of type IIb muscle fibers as well as the lowest ultimate pH (p < 0.05). The lightness value of DBS was the highest (p < 0.05). Among the three crossbred pigs, myristic, arachidic, palmitoleic, and eicosenoic acids were the highest in BDS. These results indicated that the carcass traits of local crossbred pigs were worse than those of DLY pigs, but meat quality was markedly higher, with BDS showing the best meat quality.

Using sensors to detect individual responses of lambs during transport and pre-slaughter handling and their relationship with meat quality

Rapid analysis of animal welfare is a crucial component of the assessment of the meat quality supply chain, ensuring management procedures confer optimum standards of welfare. Further, there is increasing interest in monitoring the welfare state of each individual animal. This study looked at transport and pre-slaughter management in terms of meat quality evaluated in two breeds (Biellese and Sambucana) across two different farming systems. Precision Livestock Farming (PLF) technologies were implemented, including accelerometer and rumination activity ear-tag sensors, as potential welfare indicators during transportation and pre-slaughter. Significant correlations were found between sensors' parameters, such as total activity and rumination and physical and chemical meat quality characteristics such as drip loss. Lambs with lower rumination and/or lower total activity were found to have lower drip loss indicating reduced meat quality. Sensors have the potential to help detect those animals particularly sensitive to stressors during transport and pre-slaughter handling and may allow real-time measurement of the impact of transport and handling in abattoirs, enabling better animal management via specific customised strategies.

What Is Left for Real-Life Lactate Monitoring? Current Advances in Electrochemical Lactate (Bio)Sensors for Agrifood and Biomedical Applications

Monitoring of lactate is spreading from the evident clinical environment, where its role as a biomarker is notorious, to the agrifood ambit as well. In the former, lactate concentration can serve as a useful indicator of several diseases (e.g., tumour development and lactic acidosis) and a relevant value in sports performance for athletes, among others. In the latter, the spotlight is placed on the food control, bringing to the table meaningful information such as decaying product detection and stress monitoring of species. No matter what purpose is involved, electrochemical (bio)sensors stand as a solid and suitable choice. However, for the time being, this statement seems to be true only for discrete measurements. The reality exposes that real and continuous lactate monitoring is still a troublesome goal. In this review, a critical overview of electrochemical lactate (bio)sensors for clinical and agrifood situations is performed. Additionally, the transduction possibilities and different sensor designs approaches are also discussed. The main aim is to reflect the current state of the art and to indicate relevant advances (and bottlenecks) to keep in mind for further development and the final achievement of this highly worthy objective.

Effect of Gardenia Pomace Supplementation on Growth Performance, Blood Metabolites, Immune and Antioxidant Indices, and Meat Quality in Xiangcun Pigs

To investigate the effect of gardenia pomace (GP) as an unconventional feed of antioxidants, 180 Xiangcun pigs were randomly divided into 3 groups during the finishing period, with 6 replicates per group and 10 pigs per replicate. During the 47-day feeding period, the pigs were fed either a control diet based on corn and soybean meal (control group), or the control diet added with 50 g/kg or 100 g/kg GP (groups GP5 and GP10, respectively). Feed and water were provided ad libitum. One pig per replicate was slaughtered and sampled. The effects on growth performance, meat quality, digestibility, metabolism, and immunity and antioxidant properties of the pigs were investigated. The results showed that GP had no significant effect on the growth performance of Xiangcun pigs. Compared with the control group, the digestibility of crude ash, phosphorus, and crude fibre of pigs in the GP groups improved (p < 0.01), and the content of inosinic acid in the longissimus dorsi muscle increased (p < 0.05). The addition of GP to the diet significantly increased superoxide dismutase (SOD) levels in the liver and spleen, and glutathione peroxidase (GSH-Px) activity in the longissimus dorsi muscle and spleen (p < 0.05). Additionally, it significantly reduced the contents of malondialdehyde (MDA) in the liver and spleen (p < 0.05). The GP5 group had a higher inosinic acid content in the longissimus dorsi and lower levels of the inflammatory factor interleukin-2 and interleukin-8 than those in the other groups (p < 0.05). The GP10 group had a higher IgA level (p < 0.05). Adding different proportions of GP to the diet improved the a* and b* of the longissimus dorsi muscles of Xiangcun pigs (p < 0.05). In summary, GP, as an unconventional feed, improved the apparent digestibility of the diet and body antioxidant capacity in Xiangcun pigs during the finishing period and did not negatively affect the growth performance or meat quality.

Metabolomic analysis indicates that higher drip loss may be related to the production of methylglyoxal as a by-product of glycolysis

The aim of the present study was to assess applicability of metabolomics analysis of exudate from chicken breast muscle to explanation of differences in drip loss. The research was carried out on the skinless breast fillets sourced from 60 broiler carcasses (7-wk-old male Ross broilers). In the meat samples the pH value, color parameters, drip loss, chemical composition, and sensory quality were evaluated. After measuring, the samples were divided into 2 groups taking into consideration the volume of drip loss (low ≤2% and high >2% drip loss). The muscle juice samples were collected during 24 h muscle storage and metabolomic analysis was performed. The results showed that chickens with higher drip loss were characterized by heavier carcasses. The meat with higher drip loss proved to be more acid, lighter, less red, and more yellow with higher level of glucose as well as glycolytic potential. That meat was also characterized by lower cooking loss, protein content and worse overall sensory quality as well as oxidation of lipids. The metabolomics analyses have shown that in the group with higher drip loss from muscle tissue the increase of metabolism of energy transformations taking place in muscle tissue after slaughter was observed and that differences between groups are related to 11 metabolic pathways, mainly carbohydrate metabolism (glycolysis, gluconeogenesis, pentose phosphate pathway) adenine and adenosine salvage, adenosine nucleotides degradation, arsenate detoxification, methylglyoxal degradation. Finally, the results indicate that in the group with higher drip loss and with deeper glycolysis, more methylglyoxal (as a by-product of carbohydrate metabolism) is produced which may lead to changes of muscle proteins properties and contribute to an increase in drip loss.

Applications of Biosensors for Meat Quality Evaluations

The aim of this study was to apply biosensors in the assessment of meat quality. The research was carried out on 20 samples of the Longissimus muscle obtained from pork of Polish Landrace and Polish Large White hybrids of fattening pigs. In the samples, 48 h after slaughter pH values, color parameters in the CIE system (L* a* b*), the volume of natural drip loss and intramuscular fat content were measured. The commercially available biosensor Accutrend Plus was used to measure glucose, triglycerides and lactic acid in meat juice. Significant (p ≤ 0.05) relationships between glucose, triglycerides, lactic acid levels and pork quality characteristics, i.e., pH (r = -0.62; r = -0.78; r = -0.68 respectively), natural drip loss and (r = 0.57; r = 0.58; r = 0.49), color parameters as L*, a* and b* (r = from 0.47 to 0.79) were demonstrated. The study showed a negative correlation between the intramuscular fat content and acidification of muscle tissue (r = -0.49), and a positive one with the brightness of color (r = 0.46). The results of the canonical analysis show that the measurement of all three metabolites in muscle juice allows the evaluation of the technological quality of meat with an accuracy of 86.54% (Rc = 0.93, p < 0.01).

Cold Exposure Affects Lipid Metabolism, Fatty Acids Composition and Transcription in Pig Skeletal Muscle

Cold exposure promotes glucose oxidation and modulates the lipid metabolism in adipose tissue, but it is still not fully clear whether cold exposure could affect meat quality and fatty acid metabolism in skeletal muscle of pig in vivo. Here, we kept finishing pigs under cold or room temperature overnight and determined the effects of cold exposure on meat quality, fatty acids composition and transcriptional changes in skeletal muscle of pigs. We found that cold exposure significantly reduced the meat colour_{24 h} and pH_{24 h}, without affecting carcass characteristics and other meat quality traits. Considerable changes were found in the proportions of individual fatty acids and the total content of saturated fatty acid, polyunsaturated fatty acids, monounsaturated fatty acid and n3-fatty acids. RNA-seq results showed upregulated fatty acid biosynthesis genes and downregulated mitochondrial beta-oxidation genes. The lipid metabolism in cold-treated longissimus dorsi muscle might be regulated by functions of the lipoprotein particle, the extracellular matrix, and the PPAR signaling pathways. Our study revealed the potential of cold exposure to regulate the lipid metabolism and fatty acid composition in skeletal muscle of farmed animals.

Effects of Polyunsaturated Fatty Acids Supplementation on the Meat Quality of Pigs: A Meta-Analysis

Polyunsaturated fatty acids (PUFAs) supplementation has been widely discussed as a strategy for improving meat quality in pig production, but the effects are inconsistent. This meta-analysis was performed to comprehensively evaluate its effects on the meat quality and growth performance of pigs. We searched the PubMed and the Web of Science databases (articles published from January 1, 2000 to October 16, 2020) and compared PUFAs-supplemented diets with control diets. We identified 1,670 studies, of which 14 (with data for 752 pigs) were included in our meta-analysis. The subgroup analysis was classified as PUFA source [conjugated linoleic acid (CLA) or linseed], concentration (high or low concentration), and initial stage (growing or finishing pigs). Our analysis found that PUFA supplementation increased the intramuscular fat (IMF) content (WMD = 0.467%, 95% CI: 0.312–0.621, p < 0.001), decreased the meat color L^* (WMD = −0.636, 95% CI: −1.225 to −0.047, p = 0.034), and pH 24 h (WMD = −0.021, 95% CI: −0.032 to −0.009, p < 0.001) but had no influence on drip loss, meat color a^* and b^*, pH 45 min, and growth performance. CLA supplementation improved IMF content (WMD = 0.542%, 95% CI: 0.343–0.741, p < 0.001) and reduced meat color b^* (WMD = −0.194, 95% CI: −0.344 to −0.044, p = 0.011). Linseed supplementation increased IMF content (WMD = 0.307%, 95% CI: 0.047–0.566, p = 0.021), decreased meat color L^* (WMD = −1.740, 95% CI: −3.267 to −0.213, p = 0.026), and pH 24 h (WMD = 0.034, 95% CI: −0.049 to −0.018, p < 0.001). We discovered an increase on the IMF content in both high and low concentration PUFA supplementation (WMD = 0.461%, 95% CI: −0.344 to −0.044, p < 0.001; WMD = 0.456%, 95% CI: 0.276–0.635, p < 0.001). Furthermore, we also found the effects of PUFA supplementation on meat color L^* and pH 24 h are concentration- and stage-dependent. PUFA supplementation can improve the meat quality of pigs, which mainly emerges in greatly increasing IMF content.

Effect of Heat Treatment by the Sous-Vide Method on the Quality of Poultry Meat

An increase in the consumption of poultry meat has been observed due to its availability, nutritional value, and delicate flavor. These characteristics make it possible to prepare, with the use of spices and other additives, many different dishes and products for increasingly demanding consumers. The sous-vide technique is increasingly being used to give new sensory attributes to dishes in gastronomy. The study aimed to assess the impact of the heat treatment method, i.e., the sous-vide method, as compared to traditional cooking, on the sensory quality of poultry meat, as well as the efficiency of the process with regard to technological quality. The cooking yield with the sous-vide method of processing poultry meat was higher than with the traditional method of cooking in water (88.5% vs. 71.0%, respectively). The meat was also found to be redder (a* = 254 vs. 074) and less yellow (b* = 1512 vs. 1649), as well as more tender. The sensory quality of chicken breast meat obtained by the sous-vide method was higher in terms of attributes such as color tone, tenderness, juiciness, and overall quality. At the same time, it was lower in terms of the odor of cooked meat and the flavor of cooked meat as compared to meat subjected to traditional cooking.

Biosensors in Evaluation of Quality of Meat and Meat Products – A Review

Biosensors can find application in meat and meat products testing for safety, including microbial and other contaminants, and quality, including meat freshness, beef tenderness and pork quality defects. The available biosensors enable the evaluation of freshness, the classification of tenderness of meat products, the evaluation of the glycolysis extent and the presence of the microbial and other contaminants. Since biosensors depend on receptor types, the expansion of knowledge on metabolic transformations occurring in meat contributes to the development of new potential markers and indicators. Examples include assays for glucose, lactates, hypoxanthines, calpastastins, microbial and other contaminants in meat products, augmenting conventional methods. At the same time, biosensors rely on transducers for detection, requiring achievement in many fields including nanotechnology and optics, among others. Biosensors have potential to become a fundamental tool for monitoring and controlling safety and quality of meat products in the future. Hence the aim of the present paper is to present the current state of knowledge on the application of biosensors in meat.

Physiochemical properties, protein and metabolite profiles of muscle exudate of chicken meat affected by wooden breast myopathy

The current study was designed to investigate the physiochemical properties, protein and metabolite profiles of muscle exudate obtained from chicken breast fillets affected by wooden breast (WB) myopathy. Twenty-four fillets were categorized into varying degrees of WB condition including normal, moderate and severe. Results indicated that exudate loss, free hemoglobin concentration, protein and lipid oxidation were affected by WB myopathy. Electrophoresis analysis showed eight distinct protein bands of differential relative abundance in WB samples compared with the normal, and the identified proteins were mostly involved in carbohydrate metabolic process. ¹H nuclear magnetic resonance-based metabolomics identified eleven metabolites including amino acids, nucleotides and organic acid as the most influential metabolites affected by WB myopathy. Overall, this study shows differential molecular profiles of myopathic chicken muscle exudate, and provides a valuable resource for further recognition of WB myopathy.

The effect of inulin supply to high-fat diet rich in saturated fatty acids on pork quality and profile of sarcoplasmic protein in meat exudate

The aim of the study was to evaluate the influence of inulin supply to high-fat diet rich in saturated fatty acids (SFA) on pork quality and profile of sarcoplasmic protein in drip loss. At 50 days of age, twenty cross-bred pigs (gilts) were randomly allotted to four groups: the control (C) group fed a standard diet, and three experimental (D1, D2 and D3) groups fed a high-fat diet rich in SFA. Moreover, pigs from the groups D2 and D3 consumed an extra inulin supply (7% of daily feed intake) from 85 to 120 days of age (for 5 weeks) and from 50 to 120 days of age (for 10 weeks) respectively. The addition of inulin to the diet reduced meaty odour and flavour significantly, improved tenderness and overall sensory quality of pork and additionally influenced ultimate pH, L* colour parameter, lactate level and protein content in meat. The diets also affected the profile of sarcoplasmic proteins. Significant effects were observed for the following enzymes-PK/PGI (pyruvate kinase/phosphoglucose isomerase) and ALD (aldolase), which are related to the intensity of post-mortem glycolysis. Presented data indicate that long-term inulin supply to high-fat diet has a positive effect on technological and sensory quality as well as protein profile of pork.

Meat packaging solutions to current industry challenges: A review

Many advances have occurred in the field of smart meat packaging, and the potential for these to be used as tools that respond to challenges faced by industry is exciting. Here, we review packaging solutions to several immediate concerns, encompassing dark cutting, purge and yield losses, product traceability and provenance, packaging durability, microbial spoilage and safety, colour stability, environmental impacts, and the preservation of eating quality. Different active and intelligent packaging approaches to each of these were identified and are discussed in terms of their usefulness - to processors, retailers and/or consumers. From this, it became apparent that prior to selecting a packaging solution, industry should first define their criteria for success (e.g. How much purge is too much? What is a reasonable shelf-life to facilitate product turnover? Is the customer willing to pay for this?), and understand that packaging is not the sole solution, but acts as part of a holistic response to these issues.

Versatile SPR aptasensor for detection of lysozyme dimer in oligomeric and aggregated mixtures

A Surface Plasmon Resonance (SPR) sensor for the quantitation of lysozyme dimer in monomer-dimer mixtures, reaching a detection limit of 1.4nM dimer, has been developed. The sensor is based on an aptamer which, although developed for the monomeric form, binds also the dimeric form but with a strikingly different kinetics. The aptasensor was calibrated using a dimer obtained by cross-linking. Sensorgrams acquired with the aptasensor in monomer-dimer mixtures were analysed using Principal Components Analysis and Multiple Regression to establish correlations with the dimer content in the mixtures. The method allows the detection of 0.1-1% dimer in monomer solutions without any separation. As an application, the aptasensor was used to qualitatively observe the initial stages of aggregation of lysozyme solutions at 60°C and pH 2, through the variations in lysozyme dimer amounts. Several other methods were used to characterize the lysozyme dimer obtained by cross-linking and confirm the SPR results. This work highlights the versatility of the aptasensor, which can be used, by simply tuning the experimental conditions, for the sensitive detection of either the monomer or the dimer and for the observation of the aggregation process of lysozyme.