Physicochemical Properties Of Meat Research Articles

Valorization of Dairy and Fruit/Berry Industry By-Products to Sustainable Marinades for Broilers' Wooden Breast Meat Quality Improvement.

The study aims to improve the quality of wooden breast meat (WBM) via the use of newly developed marinades based on selected strains of lactic acid bacteria (LAB) in combination with the by-products of the dairy and fruit/berry industries. Six distinct marinades were produced based on milk permeate (MP) fermented with Lacticaseibacillus casei (Lc) and Liquorilactobacillus uvarum (Lu) with the addition of apple (ApBp) and blackcurrant (BcBp) processing by-products. The microbiological and acidity parameters of the fermented marinades were evaluated. The effects of marinades on the microbiological, technical, and physicochemical properties of meat were assessed following 24 and 48 h of WBM treatment. It was established that LAB viable counts in marinades were higher than 7.00 log10 colony-forming units (CFU)/mL and, after 48 h of marination, enterobacteria and molds/yeasts in WBM were absent. Marinated (24 and 48 h) WBM showed lower dry-matter and protein content, as well as water holding capacity, and exhibited higher drip loss (by 8.76%) and cooking loss (by 12.3%) in comparison with controls. After WBM treatment, biogenic amines decreased; besides, the absence of spermidine and phenylethylamine was observed in meat marinated for 48 h with a marinade prepared with Lu. Overall, this study highlights the potential advantages of the developed sustainable marinades in enhancing the safety and quality attributes of WBM.

Impact of dietary supplementation with cinnamon bark powder on broiler growth and carcass indices, small intestinal measurements, physico-chemical properties of meat and economics of production

Impact of dietary supplementation with cinnamon bark powder on broiler growth and carcass indices, small intestinal measurements, physico-chemical properties of meat and economics of production

Correlation Analysis between Volatile Compounds and Quality Attributes in Pork Tenderloin in Response to Different Stir-Frying Processes.

Volatile compounds and physicochemical properties of meat are significantly changed by cooking processes. This study explored the influence of different stir-frying temperatures and times on the dynamic changes of the physicochemical characteristics and volatiles of pork tenderloin and determined the correlation between them. Results showed that time played more of a role than temperature. At the same temperature, the water content decreased (p < 0.05) and the cooking loss increased (p < 0.05) with stir-frying time extending. The L* value and the b* value showed first an increasing and then decreasing trend (p < 0.05), while the a* value significantly increased (p < 0.05). The higher the cooking temperature of sample, the faster the indexes changed. In stir-fried samples, 50 volatiles were identified. Correlation analysis showed that among the quality attributes, b* value and water content had the strongest impact on volatiles. The water content was negatively correlated with most of the compounds attributed to the desired aroma of stir-fried samples, while the correlation between the b* value and these volatiles was positive. Hence, changes in the types and contents of volatiles in stir-fried pork tenderloin could be predicted by detection of b* value and water content.

Effects of bee pollen inclusion on performance and carcass characteristics of broiler chickens

This study was conducted to determine the effect of bee pollen (BP) inclusion on performance and carcass characteristics in broiler chickens. A total of 240 Ross 308 broiler chicks were allocated to 4 treatments (BP inclusion levels of 0, 4, 8, or 12 g/kg DM feed) in a randomized complete block design with sex as a block having 3 replicates with 10 chickens per replicate. After 21 d, the chickens remained in their treatment groups and fed standard grower diet. The results of the current study revealed that BP inclusion had positively improved (P < 0.05) average weekly feed intake (FI), body weight (BW), body weight gain (BWG), and feed conversion ratio (FCR) in both sexes. However, the apparent nutrient digestibility, metabolizable energy (ME), and nutrient digestibility were not affected by the dietary BP. Furthermore, carcass yield in both sexes was improved (P < 0.05) by BP inclusion levels. In contrast, meat pH, shear force, and sensory evaluation in both sexes were not affected (P > 0.05). The results suggest that the broiler chicks can utilize bioactive compounds in BP when supplemented in the starter diets and subsequently improve their growth parameters throughout the growing period as well as carcass yield at slaughter age. These positive improvements could be due to high quality amino acids, essential oils, vitamins, and minerals of BP. Therefore, it is concluded that BP inclusion level of 12 g/kg or more in the starter diets could have positive effects on growth performance and carcass yield at slaughter age without causing adverse effects on meat physico-chemical properties and sensory evaluation in both male and female broiler chickens.

Physicochemical characteristics of meat from capons derived from the crossing of conserved breed hens and meat roosters

The study aimed to determine the effect of castration on physicochemical properties of meat from capons derived from the crossing of Rhode Island Red (R-11) hens and meat roosters. Subjects were 100 crossbred cockerels, which were randomly assigned to 2 groups of 50 each. Group I (control) consisted of intact cockerels and birds from group II were subjected to castration. The castration was performed at 7 wk of age under local anesthesia by a veterinarian. All birds were fed ad libitum with the same feed mixtures and placed on litter under optimal environmental conditions at a stocking density of 5 birds/m2. At the end of fattening (20 wk of age), 10 birds whose body weight was similar to group average, were selected from each group for slaughter. After slaughter, the birds were analyzed for dressing percentage and physicochemical parameters of breast and leg muscles, which were subjected to sensory evaluation. The results demonstrated that compared to intact cockerels, capons were characterized by significantly higher body weight, dressing percentage and carcass muscle content. Both the breast and leg muscles of the capons showed better physicochemical parameters and higher sensory score. It is therefore concluded that the birds derived from the crossing of Rhode Island Red (R-11) hens and meat roosters are good material for capon production, their meat is a product of distinctly higher quality.

The Quality of Duck Meat from the Perspective of Physical Measurements and Expert Judgment

Abstract The aim of this study was to evaluate the relationships between some physicochemical properties and organoleptic assessments of duck meat quality and expert assessment of the general appearance of raw breast and leg muscles. Body, carcass, breast and leg muscle weight were analysed. For both breast and leg muscles the following parameters were recorded: water holding capacity, thermal drip, colour lightness L*, electrical conductivity after 15 minutes and 24 hours post mortem, as well as four traits subject to expert organoleptic evaluation (general appearance, colour, odour and fatness). The dependence was evaluated using the Pearson’s correlation and multiple regression equations (the general appearance was treated as a dependent variable). Three sets of variables were considered as factors influencing the general appearance of the raw breast and leg muscles. First, the influence of jointly selected performance traits and physicochemical properties of meat was analysed. Next, the impact of only the second-mentioned group of discriminants was considered, and then the dependence on other organoleptic attributes. It was shown that for both muscle groups, the following have a significant effect on the general appearance: muscle weight (breast muscle P&lt;0.0001, leg muscle P&lt;0.0001) in the first set, electrical conductivity 15 minutes after slaughter (breast muscle P = 0.023, leg muscle P = 0.042) in the second, and colour (both muscle groups P&lt;0.0001) in the third. Muscle weight, electrical conductivity 15 minutes post mortem and visually assessed colour can be used to make a preliminary assessment of the technological and culinary quality of duck meat. Moreover, measurement with a conductometer is an economical and fast method, possible to carry out in a slaughterhouse.

Use of zinc oxide nanoparticles in the growing rabbit diets to mitigate hot environmental conditions for sustainable production and improved meat quality

BackgroundThis study evaluated the modulatory effects of zinc oxide nanoparticles (ZnO-NPs) supplementations on the productive performance, blood biochemistry, carcass criteria, and meat quality of White New Zealand rabbits reared under hot conditions. A total of 125 White New Zealand male rabbits (body weight, “650 ± 11”, 30 days old) were assigned to five treatment diets: basal diets supplemented with ZnO-NPs at 0, 20, 40, 60, or 80 mg/kg for 60 days. Each treatment was replicated 25 times with one rabbit each.ResultsThe body weight (BW), BW gain, and feed intake linearly increased with zinc oxide nanoparticle supplements. Supplementation of ZnO-NPs at 20, 40, 60, and 80 mg/kg significantly improved (linear, P < 0.05) the feed conversion ratio compared to the control group. Moreover, supplementation of ZnO-NPs at these inclusions 20, 40, 60, and 80 mg/kg significantly (P < 0.05) decreased the serum cholesterol, alanine aminotransferase, and aspartate aminotransferase, creatinine, and urea compared to control group. The lipid oxidation was lower, and the water holding capacity of rabbit meat was improved (P < 0.001) in rabbits fed on 20, 40, 60, and 80 mg/kg ZnO-NPs supplemented diets compared to control.ConclusionThe results suggested that dietary supplementation of ZnO-NPs (20–80 mg/kg) can mitigate the negative impacts of heat stress on rabbit performance and health. Its supplementation improved growth performance and meat physicochemical properties, and blood biochemistry parameters of White New Zealand rabbits.

Diets Composed of Tifton 85 Grass Hay (Cynodon sp.) and Concentrate on the Quantitative and Qualitative Traits of Carcass and Meat from Lambs

The high intake of fermentable carbohydrates may cause nutritional disorders and negatively affect animal performance. Thus, the research study aimed to determine the better roughage:concentrate ratio to improve the carcass traits and physicochemical quality of meat from feedlot-finished Santa Ines lambs. Diets were composed of Tifton 85 grass hay (Cynodon sp.) and concentrate (soybean meal, corn meal, urea, and mineral mixture) and consisted of five roughage:concentrate ratios of 88:12 (C12), 69:31 (C31), 50:50 (C50), 31:69 (C69), and 12:88 (C88). After 63 days the animals were slaughtered and carcass traits, the yield of commercial cuts, and physicochemical properties of meat were evaluated. The higher percentage of concentrate on roughage provided higher DM intake, better feed conversion, higher conformation, finishing, and carcass yield that resulted in heavier commercial cuts with higher fat content in the meat. The addition of 50% concentrate to the roughage improved the carcass traits, commercial cuts, and physicochemical parameters of the meat in a similar way to the diet with 88% concentrate, but with leaner meats, meeting the demands of the current consumer market.

Dietary Plukenetia conophora seed alters muscle cholesterol, antioxidant enzymes, and fatty acids in growing rabbits

The influence of dietary inclusion of Plukenetia conophora seed (PCS) on growth, carcass, muscle antioxidant enzymes, fatty acids, meat quality, and sensory attributes of Longissimus thoracis et lumburum muscle in rabbits was examined. Seventy-two, 28 d old male New Zealand rabbits (750 ± 20 g) were randomly allotted to diets containing either no PCS (PCS-0), 2.5% PCS (PCS-2.5) or 5% PCS (PCS-5) for eight weeks, and euthanized. PCS-5 rabbits had higher (P < 0.05) body and carcass weights than the PCS-0 rabbits. Dietary PCS improved feed efficiency in rabbits. Muscle antioxidant enzymes activities and total phenols were higher while muscle cholesterol was lower (P < 0.05) in supplemented meat than the PCS-0 meat. The concentration of C22:6n-3, C20:5n-3 and C18:3n-3 was higher (P < 0.05) in the supplemented meat than the PCS-0 meat. Sensory attributes, carbonyl, and TBARS values and physicochemical properties of meat did not differ among diets. Supplementation of PCS-5 enhances muscle n-3 fatty acids without impairing the sensory properties, and oxidative stability of rabbit meat.

Quality of Cattle Meat and Its Compositional Constituents.

Meat is the most valuable livestock product since it is one of the main sources of protein for human consumption. Meat quality can be evaluated according to the following parameters: pH, amount of lactic acid, volatile fatty acids, bounded water, solubility of proteins, color, and tenderness. The meat composition and physical properties of muscles have been characterized for ensuring improved eating quality. Thus, the purpose of this paper was to review the major chemical compositional and physicochemical properties of meat and, at the same time, its quality attributes and factors that affect quality of meat. A number of structural features of meat as connective tissue, muscle fibers, and tendon that attaches the muscle to the bone are visible in joint meat examined through naked eyes. Water is quantitatively the most important component of meat comprising up to 75% of weight. Meat is also composed of amino acids, fatty acids, vitamins, minerals, and other important ingredients. Quality factors perceived by consumers are related to sensory attributes (e.g., color, tenderness, and flavor), nutritional properties (e.g., calories, vitamins' content, and fatty acids' profile), and appearance (e.g., exudation, marbling, and visible amount of fat). However, fresh meat quality can be defined instrumentally including composition, nutrients, color, water-holding capacity, tenderness, functionality, flavors, spoilage, and contamination. Visual inspection based on sensory quality attributes and different chemical methods are used to analyze meat quality. Other methods such as computer vision and imaging spectroscopy, gas chromatographic analysis, near-infrared technology, dual-energy X-ray absorptiometry, and computerized tomography scanning are also used in the meat industry. So, the aim of the present review is to review quality characteristics of cattle meat and its composition constituents.

Influence of Crescentia cujete and Launaea taraxacifolia leaves on growth, immune indices, gut microbiota, blood chemistry, carcass, and meat quality in broilerchickens.

The rising concerns pertaining to the safety of synthetic supplements in livestock production have encouraged the exploration of potential alternatives. This study investigated the growth, gut microbiota, blood chemistry, immune indices, meat quality, and antioxidant status in broiler chickens supplemented with Crescentia cujete leaf (CCL), Launaea taraxacifolia leaf (LTL), and a combination of antibiotic (70% oxytetracycline + 30% neomycin) and tert-Butylhydroxyanisole. One-day-old Ross 308 chicks (n = 420) were randomly assigned to either T-1, basal diet (BD) only; T-2, BD + 0.4g/kg antibiotic + 0.13g/kg tert-butylhydroxyanisole; T-3, BD + 2.5g/kg LTL; T-4, BD + 5g/kg LTL; T-5, BD + 2.5g/kg CCL; or T-6, BD + 5g/kg CCL for 42days. Each dietary group had seven replicates with ten chicks per replicate. Body weight gain and carcass weight were higher (P < 0.05) in the T-2, T-4, T-5, and T-6 birds compared with those of other birds. At 1-21days, the T-2 and T-4 birds consumed more feed than the T-1 and T-3 birds. At 22-42days, the T-4 birds consumed more (P < 0.05) feed than the T-1 and T-3 birds. During 1-42days, the T-1 and T-3 birds consumed less (P < 0.05) feed than other birds. At 22-42days and 1-42days, the T-1 had lower feed efficiency (P < 0.05) than other birds except for the T-3 birds. The CCL and LTL birds had lower (P < 0.05) serum LDL cholesterol and higher HDL cholesterol compared with other birds. Hematology, splenic interleukin-1β, immunoglobulin M, ileal and caecal total aerobic bacteria counts, caecal Lactobacillus spp., and meat physicochemical properties were unaffected by diets. The T-1 birds had higher (P < 0.05) ileal and caecal Clostridium spp., E. coli, and Salmonella spp. compared with birds fed other diets. The CCL and LTL birds had higher ileal Lactobacillus counts. Splenic IL-10 was higher (P < 0.05) in the T-2, T-4, and T-6 birds compared with that in other birds. Dietary supplementation with CCL, LTL, and a combination of antibiotic and tert-butylhydroxyanisole repressed (P < 0.05) splenic tumor necrosis-α and immunoglobulin G. The T-1 breast meat had lower glutathione peroxidase and catalase. The T-4 meat had higher (P < 0.05) superoxide dismutase, glutathione peroxidase, catalase, and total antioxidant capacity compared with other meats. On day 3 postmortem, meats obtained from birds supplemented with CCL, LTL, and a combination of antibiotic and tert-butylhydroxyanisole had lower (P < 0.05) carbonyl and malondialdehyde contents than the meat from the non-supplemented birds. The 5g/kg CCL and 5g/kg LTL could be used as antimicrobial and antioxidant in broiler diets.

Meat Quality and Carcass Characteristics Assessments in Broiler Chickens Subjected to Different Pre-Slaughter Feed Withdrawal Times

The aim of this study was to evaluate the effect of different pre-slaughter feed withdrawal on broiler chickens meat yield and quality. Eighteen 42-d-old broilers were submitted to either 9 hours pre-slaughter feed withdrawal, 12 hours pre-slaughter feed withdrawal or 15 hours pre-slaughter feed withdrawal. At the end of each fasting times, the birds were slaughtered following the halal slaughter procedure to assess carcass and meat quality characteristics. The results indicated no differences (P>0.05) in the physicochemical properties of meat among different pre-slaughter fasting times. However, broiler fasted 15 hours possessed the lowest (P<0.05) carcass yields than others. It can deduce that 9h pre-slaughter feed fasting duration had better efficiency on carcass and quality of meat traits but pre-slaughter feed withdrawal duration can last up to 12 hours. Therefore, more investigations are needed to study 9 or 12 hours pre-slaughter feed fasting times on other factors such as carcass contamination and lipid oxidation.

The Effect of Point Mutations in the RYR-1 Gene on the Physicochemical Properties of Meat

The impact of gene mutations in the RYR-1 gene on the physicochemical qualities and nutritional value of homozygous and heterozygous stress-resistant NOR carcasses with RSE and DFD defects was studied using molecular genetics methods. NOR, which is meat of homozygous cross-breeding pigs, had a 0.44 higher pH level, 2.62% higher water-holding ability, 2.36 units×103 higher color and 0.37% higher content of organic matter; the tryptophan content and protein-quality index were lower by 0.3 mmol/g and 0.29, respectively. This low acidity caused the denaturation of some sarcoplasmic proteins, which contributed to the loss of the meat’s water-holding ability. A sharp decrease in pH led to partial denaturation of the sarcoplasmic proteins, which determined the pale color of the PSE meat. It was found that, compared to the heterozygous stress-sensitive animals with DFD defects, the NOR pH level was 0.55 lower, the water-holding ability was 4.05% lower, and the color intensity was 4.97 units×103 lower; the protein-quality indicator amounted to 8.24, which was 1.12 higher than that in the heterozygous stress-sensitive animals with DFD defects. The defects had a significant impact on other physicochemical properties of the meat. Defects of PSE meat worsened meat color. The intensity of staining of muscle tissue with PSE defects was lower than in normal pork by 11.5, 8.7 and 6.4 units×103 , respectively. DFD-pork exceeded normal meat in color by 13.7 (P&gt; 0.99), 9.5 (P&gt; 0.99) and 7.4 units×103 .&#x0D; Keywords: stress tolerance, stress sensitivity, genotype, meat defects PSE and DFD-, RYR-1 gene, pH, water-holding ability, meat coloring

Effects of Stocking and Transport Conditions on Physicochemical Properties of Meat and Acute-Phase Proteins in Cattle.

This study’s objective was to evaluate the effects of distance and stocking density on physicochemical properties and oxidative stability of meat and acute-phase proteins in Brahman crossbred cattle transported by road under hot and humid tropical conditions. Sixty Brahman crossbred heifers were subjected to road transport from a cattle feedlot farm located in Universiti Putra Malaysia (UPM), Serdang, to a commercial ruminant abattoir in Shah Alam, Selangor. Animals were assigned to long and short distances and high, medium, and low stocking densities. The results revealed that the intensity of response significantly increased in meat samples from animals subjected to long-distance transportation and higher stocking density. Alpha-1-acid glycoprotein and serum amyloid-A values increased considerably and were different from the baseline values recorded at preload. In conclusion, the current results revealed that the color, pH, shear force values, water holding capacity (WHC), glycogen level, and malondilaldehyde assay (MDA) concentrations in meat and acute-phase proteins (APP) were affected by both distances and stocking densities, as evidenced by the significant changes recorded from the parameters above.

The use of probiotics in the cultivation of turkeys

The specific microclimate of poultry premises contributes to the accumulation of microflora, which may contain pathogenic and opportunistic microorganisms. The concentration of microorganisms in poultry houses increases over time and reduces the resistance of the bird. Researchers have reported very high growth rates of mesophilic aerobic microorganisms, which include most pathogenic bacteria, namely: gram-positive cocci (staphylococci, enterococci) and gram-negative bacteria of the family Enterobacteriaceae (Escherichia coli, Salmonella spp., Salmonella spp.). Proteus spp., Klebsiella spp., and Pseudomonas spp. The goal of our research was to investigate and compare the effectiveness of two probiotics for turkeys, one of which contains recombinant strains of lactic acid microorganisms of intestinal intestinal symbionts, and the other based on a mixture of biologically active substances based on natural components of organo-mineral origin. The task of our work: 1. To study the microflora of the gastrointestinal tract during the use of probiotics after the use of antiparasitic drugs in nematode invasion of turkeys. 2. Compare the growth of young animals with the use of probiotics and provide suggestions on the prospects for the most effective use of probiotics in the cultivation of turkeys. 3. Investigate changes in the physicochemical properties of turkey meat when using probiotics and compare them with controls. To conduct the experiment, three experimental groups of turkeys cross Hybrid converter, 14 days old, each with 10 heads. The first and second experimental groups were given an antiparasitic drug containing levamisole hydrochloride at a dose of 5 ml per 5 liters of water once. After that, probiotics were used for each experimental group of birds. Two types of probiotics were used in the experiments: the first contains recombinant strains of lactic acid microorganisms of intestinal intestinal symbionts: Bifidobacterium bifidum, Bacillus thermophilus, Bacillus coagulance, Bacillus subtilis. Has antimicrobial, antiviral and antioxidant activity; the second preparation contains a mixture of biologically active substances, based on natural ingredients of organo-mineral origin, which includes organic substances – fulvic and humic acids. The third group (control) used only the above antiparasitic drug. After the experiment, at the age of 78 days, poultry was slaughtered and studies of the effect of probiotics on weight, physicochemical parameters of meat. When testing turkeys for helminths. As a result of research, helminths were identified, which were attributed to the causative agent of heterakidosis - Heeterakis gallibarum. After that, it was decided to carry out deworming with levamisole hydrochloride. After a course of treatment, it was found that no deaths were observed in the first experimental group; in the second experimental group, one head died, and in the third control group, which did not use probiotics, the death was two heads. The use of probiotics due to competition reduces the level of total bacterial contamination and coliform bacteria in the experimental groups. And the level of lactic acid bacteria in the experimental groups was higher than in the control. The use of probiotics had a positive effect on weight gain of experimental turkeys, compared with the control group, where probiotics were not used. The difference in the first experimental group compared with the control averaged 618 g, and in the second group – 198 g. Post-mortem examination of turkey carcasses showed that the indicators of the experimental and control groups differ. In terms of external organoleptic characteristics, the meat obtained from the slaughter of experimental birds does not differ from the meat of poultry in the control group. Conclusions and prospects for further research. The use of probiotics based on lactic acid bacteria proved to be the most effective and ensured the complete preservation of livestock. Due to competition, it reduced the level of coliform bacteria by an average of 6.67 % in the experimental groups; the level of lactic acid bacteria in the experimental groups was 4.89 % higher than in the control. The use of probiotics increased the weight gain of poultry by 3.28 %. No significant effect on the organoleptic and physicochemical properties of meat was observed.In the future it is planned to study the microflora of turkey slaughter products.

Effects of Caponization on Growth Performance and Meat Physicochemical Properties of Crossbred Chickens

Abstract The aim of the study was to determine the effect of caponizing on body weight and physicochemical properties of meat of the capons – hybrids obtained from the crossing of hens of the Yellowleg Partridge (Ż-33) breed with meat roosters. The study covered 80 hybrid roosters, which were randomly assigned to two groups of 40 animals each (8 boxes of 10 birds in each group). Group I (control) consisted of uncastrated roosters while group II included birds, which were castrated at 8 weeks of age under local anaesthesia by a vet. Birds were fed ad libitum with the same standard diets and kept on litter under optimal environmental conditions with a stocking density of 7 animals/ m2. At the end of fattening, i.e. in the 20th week of life, 8 birds with a body weight close to the group average were selected from each group for slaughter. After slaughter, the effectiveness of the procedure was checked (lack of testicles), then the slaughter performance of birds, physicochemical parameters of the pectoral and leg muscles were determined, and sensory evaluation was performed. The procedure of castration of hybrid roosters had a positive effect on body weight, feed conversion ratio and carcass traits. The pectoral and leg muscles of the capons were characterized by better water absorption, tenderness and sensory evaluation compared to roosters. Among the assessed groups of birds there was also a variation in the colouring of whole carcasses and muscles, which were lighter (L*), more yellow (b*) and less red (a*) in caponized birds. In addition, the castration procedure had a positive effect on the total protein content in both the pectoral and leg muscles, which in turn, with a higher raw fat content, were distinguished by a favourable ratio of n-6/n-3 polyunsaturated fatty acids (PUFA). Based on the results, it can be concluded that the hybrids obtained from the crossbreeding of the Yellowleg Partridge (Ż-33) and Ross 308 meat roosters are good choice for capon production. They can complement poultry meat production with a niche product for consumers looking for products of exceptional quality.

Discrimination of Meat Produced by Bos taurus and Bos indicus Finished under an Intensive or Extensive System.

Simple SummaryThis research was carried out to investigate the usefulness and reliability of meat quality traits such as physicochemical properties and fatty acid profiles to discriminate between meat produced by taurine and zebu cattle, finished on pasture or grain. This approach is of utmost importance to assess the authenticity of meat products, particularly when beef is certified based on criteria such as breed and finishing system. Our results using discriminant analyses indicate that meats originating from pasture- or grain-finishing can be discriminated with high reliability, essentially on the basis of their fatty acid profile. The global distinction of meat from the two genetic groups is somewhat more difficult to achieve reliably. Still, prior knowledge of the finishing system used to produce meat from a given genetic group enhances the trustworthiness of the assignment procedure, allowing the reliable allocation of meat samples originating from Bos indicus and Bos taurus finished on pasture or grain, with fatty acid profiles being better discriminating factors than physicochemical properties. These results can be adopted as tools to be used in meat certification programs.Meat obtained under commercial conditions shows considerable variability, mostly due to genetic background and production system. In this study, meat physicochemical properties and fatty acid profiles were analysed to investigate the feasibility of using them as tools to discriminate between meats produced by different genetic groups and finishing systems. Samples of the Longissimus thoracis were collected from 160 commercial bulls of the B. taurus (n = 75) and B. indicus (n = 85) groups, finished either on pasture (n = 46) or with grain supplementation (n = 114) and analysed by standard procedures. Data were analysed by discriminant analysis using a stepwise procedure, to select the meat characteristics that better contribute to discriminate the various groups. Our results indicate that fatty acid profiles of meat had better discriminating ability than physicochemical properties, especially to identify meat from animals finished on grain or pasture. The overall discrimination of meat from different genetic groups was achieved with a slightly lower reliability. Nonetheless, our results show that reliability of allocation to genetic group can be improved if prior information on finishing system is considered. These results are of high importance because they can be incorporated as tools to assess the authenticity of beef, particularly in meat certification programs.

Study on the mechanism of KCl replacement of NaCl on the water retention of salted pork.

The reasons for the change in the water retention capability of salted pork caused by potassium chloride (KCl) instead of sodium chloride (NaCl) were investigated. Accompanied by the gradually increased substitution rate of KCl, the oxidative degradation of protein, water content, water activity (aw), gap, as well as water loss in salted pork were increased, and the results showed significant differences (p<0.05). LF-NMR results indicated that NaCl was replaced by KCl, which can observably increased the mobility of water in the salted pork (p<0.05). All indexes showed excellent correlation. NaCl was replaced by KCl, which affected the water retention capability of salted pork, because K+ promoted changes in the meat's physicochemical properties. The KCl replacement group presented higher water content, while displayed lower water retention capability.

Relationship between protein markers and the sensory/physicochemical parameters of ovine meat during refrigerated storage

Description of the subject. Commercialization requires the storage of meat for a period of time according to the distribution and supply chain, usually under refrigeration and vacuum packaging. During this stage, many biochemical reactions can modify the sensory and physicochemical properties of meat. Proteolysis is one of the most important of these reactions as proteins are the building blocks of muscle, and their degradation affects tenderness. Objectives. The objectives of this study were to use multiple factorial analyses to correlate the physicochemical, sensory, and proteolytic changes in ovine meat during refrigeration. Method. Each loin was separated and randomly assigned to day 3, 5, or 14. Sensory panel evaluated the meat for appearance, odor and texture parameters. Warner-Bratzler shear force and texture profile analysis were evaluated. Similarly, protease activity was evaluated. Samples for 2D-electrophoresis and western blotting were collected at days 3, 5, and 14 post mortem. The results were analyzed by multiple factorial analyses. Results. The relative protein levels of desmin, vinculin, and myosin were found to decrease with time. Multiple factor analysis showed that the Warner-Bratzler shear force (WBSF) was highly correlated with the relative desmin concentration, the relative vinculin concentration, and acidic protease activity. The activities of acidic and neutral proteases were positively correlated with myosin level on day 3, but were negatively correlated with manual tenderness and myosin level on days 5 and 14. Conclusions. Therefore, desmin, myosin and vinculin, which correlate with sensory and physicochemical parameters during refrigerated storage, may prove useful as markers for tenderness.

Microbiological status and oxidation properties of minced chicken breast meat treated with different concentrations of Allyl-isothiocyanate

Due to its biological composition, poultry meat is perishable by nature and susceptible to quality deterioration such as microbial spoilage and oxidation changes. Meat and meat products with healthy, extended shelf-life and good organoleptic properties are highly demanded by consumers. In current study, the antimicrobial and antioxidant effects of allyl-isothiocyanate (AITC) as a natural additive on raw chicken meat during chilling storage were determined. For this purpose, samples of minced were treated with different concentrations of AITC (100, 200, 300 and 500 ppm) and control no AITC added, the samples packaged and stored for 8 days at 4 °C. Fluctuations with no significant effect were noticed in TBARS values during the storage period. Simultaneously, AITC with higher concentration showed lower mesophilic aerobic counts compared to control and meat containing a low concentration of AITC. Moreover, compared to the beginning of storage, AITC decreased water holding capacity (WHC) of meat this can affect other physicochemical properties of meat. Further study needed to determine the effect of AITC on the physicochemical properties of meat and food products.