Enhancing shelf life of bison meat using CO2/N2 modified atmosphere master bag packaging system with oxygen scavengers

This study aimed to assess the impact of CO2/N2 modified atmosphere master bags (MB) and the incorporation of oxygen scavengers on color stability, oxidation development, and microbial growth in bison meat during storage and retail exposition. The utilization of MBs with oxygen scavengers (MBOSC) led to a substantial decrease in residual oxygen levels to 0.11 % over a 14-d storage period, compared to MBs with no oxygen scavengers (2.45 %; MBNoSC) (P < 0.01). Throughout the storage and retail display simulation, MBOSC consistently increased a*, b*, and Chroma values, and with diminished Hue values compared to MBNoSC (P < 0.01). Also, MBOSC showed lower levels of lipid and protein oxidation compared to the MBNoSC samples during storage (P < 0.01). Except for the psychrophilic, other bacteria indicators remained unaffected by the MB type. Thus, MBOSC proved more effective than MBNoSC in extending the shelf life of bison meat during storage and retail display.

An exploratory study on the quality of the Longissimus thoracis et lumborum muscle of impala (Aepyceros melampus), mountain reedbuck (Redunca fulvorufula) and springbok (Antidorcas marsupialis) in South Africa

Physicochemical quality, fatty acids, volatile compounds and shelf-life profiles of the longissimus thoracis et lumborum muscle of three game species: impala, mountain reedbuck and springbok harvested from a private game estate were measured. Average live weight at slaughter that ranged from 28 to 36 kg was included in the study. The carcass weights were recorded 24 h after slaughter. The longissimus thoracis et lumborum (LTL) muscle was sampled for meat analyses. Impala and springbok LTL had higher (P ≤ 0.05) pH24 and cooking loss values than the mountain reedbuck. In addition, the springbok had more tender (P ≤ 0.05) meat than the impala and mountain reedbuck. The mountain reedbuck and springbok had higher (P ≤ 0.05) proportions of oleic acid, total monounsaturated fatty acids (FA), linoleic acid, omega (n)-6 polyunsaturated FA, and alpha-linolenic acid compared to impala. During retail display, redness and chroma decreased over time, while yellowness and hue showed an upward trend for all species (P ≤ 0.05). It was observed that species affected meat quality, total proportions of fatty acids and volatile compounds.

Fibre Sources on Performance and Carcass and Meat Characteristics of Feedlot Nellore Young Bulls

We evaluated the replacement of neutral detergent fibre levels from forage (NDFfor) by cottonseed cake on the performance, and carcass and meat traits of Nellore young bulls finished in a feedlot. Individual data from 24 Nellore young bulls with 330 ± 4.54 kg of body weight (BW) and 18 ± 1 months old were used. The animals were randomly distributed in four nutritional treatments containing 9.5%; 5.5%; 2.5%; and 0.0% NDF from whole corn plant silage (forage source), replaced by cottonseed cake, in the total diet. Animal performance and carcass and meat characteristics were analysed by orthogonal polynomial regression. A positive quadratic effect was observed for DM, CP, EE, NDF, and physically effective NDF intake (peNDFI8 mm, and peNDFI1.18 mm). There was no NDFfor-level effect for final weight, hot carcass weight, carcass yield, internal and external depth, carcass length, pH, subcutaneous fat thickness, and loin eye area. A positive quadratic effect was detected for average daily gain. Feed efficiency demonstrated a positive quadratic trend, reaching an optimum peak level when young bulls 4.01% of NDFfor. There was no NDFfor-level effect for meat and fat colour variables. The NDFfor-level with the highest DM intake (2.01% BW) was 5.15%, and the highest ADG (1.54 kg/day) was 4.91% of NDFfor. Thus, although NDFfor levels did not affect carcass characteristics, fat, and meat colour, levels between 4.50% and 5.15% NDF from forage replaced by cottonseed cake are recommended to enhance the productive performance of feedlot Nellore young bulls. Cottonseed cake as a source of fibre can partially or totally replace corn plant silage.

Influence of Loading Density and Gender on the Welfare and Meat Quality of Horses During Transport for Slaughter

The aim of this study was to determine the effects of loading density and gender on blood welfare indicators, carcass bruises and horsemeat quality. Data were collected from twelve transports of 89 slaughter horses originating from the same collection centre. The transportation of slaughter horses at high loading densities (>200 kg/m2), especially stallions, resulted in increased levels of lactate (p = 0.021), glucose (p < 0.0001), ceruloplasmin (p < 0.0001) and AOPP (p < 0.0001), but lower GSH levels (p < 0.0001). Compared to stallions and mares, geldings subjected to high loading density (>200 kg/m2) during transport had lower levels of the aforementioned blood metabolites. In addition, stallions exposed to a high load density (>200 kg/m2) had the highest frequency of severe (p = 0.0002), large (p < 0.0001) and circular (p = 0.0001) carcass bruises, which were predominantly located on the abdominal (p = 0.0056) and thoracic (p = 0.0004) wall. In contrast, a higher percentage (p < 0.0001) of undamaged carcasses was found in slaughter horses exposed to a low loading density (≤200 kg/m2) during transport. Stallions exposed to high loading densities (>200 kg/m2) during transport had the highest initial pH (p < 0.0001) and ultimate pH (p = 0.005) in terms of m. longissimus lumborum and redness (p = 0.017), but the lowest drip loss (p = 0.050) and lightness (p < 0.0001), which, consequently, led to the highest (p = 0.0045) proportion of DFD-like defects in the meat quality. In conclusion, the results of this study showed that high loading densities (>200 kg/m2), regardless of gender, negatively affect horse welfare during transport. In addition, stallions were more sensitive to poor pre-slaughter conditions and produced the lowest meat quality, while geldings were the most resistant. To determine the optimal transport density, further research is needed to determine the effects of different loading densities on the behaviour, physiology, carcass and meat quality of slaughter horses.

Effect of partial mutton meat substitution with Bambara groundnut (Vigna subterranea (L.) Verdc.) flour on physicochemical properties, lipid oxidation, and sensory acceptability of low-fat patties

Health concerns regarding fat consumption, as well as shifts in customer preference, have prompted substantial studies into low-fat products. This study examined the nutritional, color, functional, and antioxidant properties of Bambara groundnut (BGN) flour varieties (cream, brown, and red-coated) grains as well as their influence on the physicochemical properties, lipid oxidation, and sensory acceptability of low-fat mutton patties. The patties were formulated with 2.5%, 5%, 7.5%, and 10% of BGN flour for each variety, and 100% mutton patties were used as a control. The BGN flours showed significant (p < .05) differences in their nutritional composition (except for ash content), color, functional (excluding emulsion stability), and antioxidant properties. The increase in the percentage of substitution of BGN flours significantly increased the fiber (0.00% to 0.79%), ash (1.16% to 1.99%), and carbohydrates (2.14% to 1.99%) contents of the formulated mutton patties. However, moisture and protein contents decreased. The cooking yield of the formulated patties significantly increased with the increase in the percentage substitution of BGN flours (2.5%-10%), with values ranging from 76.39% to 86.80%, but the diameter reduction was limited. The increase in the inclusion of BGN flours significantly increased the lightness, hue angle, color difference, and whiteness of patties. Nevertheless, the redness, yellowness, chroma, and yellowness index of the patties decreased. The hardness and resilience of formulated patties significantly increased, with values varying from 16.41 to 17.66 N, and from 0.35 to 0.48 J/J, respectively, whereas the springiness, cohesiveness, and chewiness decreased. The lipid oxidation of formulated mutton patties significantly increased from Days 7 to 21, but was still less than that of the control sample within storage days. The sensory properties of formulated patties were not significantly different from the control sample and were above the acceptable score of five. All BGN varieties had positive effects on the mutton patties, more especially red, followed by brown, and cream, respectively. The inclusion of a 10% red BGN flour variety is highly recommended due to its significant impact on mutton patties. Nevertheless, different types of BGN varieties can each be used as additives in mutton patties without having detrimental effects on the quality parameters of the patties.

High-intensity ultrasound improves color and oxidative stability of beef from grain-fed and pasture-fed Nellore cattle

This research aimed to evaluate the influence of high-intensity ultrasound (HIU) levels (control: 0; high: 747.79; ultra-high: 1344.17 Wcm-2) on pH, instrumental color (redness, R630/580, hue angle and chroma) and oxidative stability (lipid and protein oxidation) of Psoas major (PM) muscle from Nellore cattle raised in two feeding systems: grain and pasture. Using a structural equation modeling (SEM) approach, the relations (P > 0.05) between exogenous (HIU levels) and endogenous (pH, color, lipid and protein oxidation) variables were observed. In beef from grain-fed animals the pH was directly and negatively related to lipid oxidation (γ = -0.321), hue angle (γ = -0.847) and chroma (γ = -0.442) and protein oxidation (γ = -0.752). In PM from pasture-fed HIU exhibited a negative relation with lipid (γ = -0.144) and protein (γ = -0.743) oxidation, suggesting a possible positive influence on the oxidative stability of meat and a positive relation with redness (γ = 0.197) and R630/580 (γ = 0.379). The HIU positively influenced the color and oxidative stability of beef from Bos indicus cattle, and a synergistic effect of HIU and feeding system on beef from pasture-fed animals.

Effects of nomadic grazing system and indoor concentrate feeding systems on performance, behavior, blood parameters, and meat quality of finishing lambs

The objective of the study was to evaluate the effects of three production systems on growth performance, behavior, blood parameters, carcass characteristics, and meat quality. A total of 30 lambs (n = 10 lambs/treatment) were randomly assigned to three production systems that included rotational grazing (NG) and two different levels of concentrate (CON), one with medium (roughage/concentrate ratio 50:50% based on DM, MC) and one with high concentrate (roughage/concentrate ratio 30:70% based on DM, HC) during the 90-day fattening period. At the start of the experiment, all lambs averaged 90 ± 4 days of age (mean ± SD) and were slaughtered at an average of 180 ± 3 days (mean ± SD). CON-fed lambs had higher average daily gain and loin thickness than NG-fed lambs. The NG lambs spent more time eating, drinking, and standing, but less time resting and rumination than the CON-fed lambs. In addition, plasma lipid, β-hydroxybutyrate, and urea levels were higher, while phosphorus levels were lower in NG-fed lambs than in CON-fed lambs. CON-fed lambs had better carcass yield, but gastrointestinal tract and rumen weights were lower than NG lambs. CON-fed lambs had higher pH values 0 h post mortem than the NG lambs; however, there was no effect of treatment on pH 24 h post mortem. The post-mortem color of the LD muscle of NG lambs had a higher lightness and yellowness index and a lower redness index than that of the LD muscle of CON-fed lambs. The results of this study showed that lambs fed CON had better carcass yield than lambs fed NG, although feed intake, feed conversion ratio (FCR), growth performance, carcass yield, and meat quality of lambs fed MC and HC were similar.

Physical properties during a 28-day ageing period of blesbok (Damaliscus pygargus phillipsi) Longissimus thoracis et lumborum and Biceps femoris muscles

The study aimed to determine the effect of sex, muscle-type, and ageing on the physical properties of blesbok (Damaliscus pygargus phillipsi) Longissimus thoracis et lumborum (LTL) and Biceps femoris (BF) muscles. Randomly assigned steak samples from twenty mature blesbok (10 of each sex) antelope were vacuum-packed and stored at 4.4 ± 1 °C for 2, 4, 7, 10, 17 and 28 ageing days. Cumulative purge loss, pH, colour (L*, a*, b), cooking loss, and Warner Braztler shear force were determined. Males had meat with higher (P = 0.032) pH values than females, while all other attributes were similar (P > 0.05). The LTL had greater (P < 0.05) purge losses, L* and a* values than the BF muscle, while other quality attributes were greater (P < 0.05) for the BF muscle. Despite fluctuations, there was an overall decrease in shear force with ageing time. According to all quality parameters measured, the optimum ageing period for blesbok would seem to be 10 days.

Exploratory lipidome and metabolome profiling contributes to understanding differences in high and normal ultimate pH beef

The aim of this work was to compare the lipidome and metabolome profiling in the Longissimus thoracis muscle early and late postmortem from high and normal ultimate pH (pHu) beef. Lipid profiling discriminated between high and normal pHu beef based on fatty acid metabolism and mitochondrial beta-oxidation of long chain saturated fatty acids at 30 min postmortem, and phospholipid biosynthesis at 44 h postmortem. Metabolite profiling also discriminated between high and normal pHu beef, mainly through glutathione, purine, arginine and proline, and glycine, serine and threonine metabolisms at 30 min postmortem, and glycolysis, TCA cycle, glutathione, tyrosine, and pyruvate metabolisms at 44 h postmortem. Lipid and metabolite profiles showed reduced glycolysis and increased use of alternative energy metabolic processes that were central to differentiating high and normal pHu beef. Phospholipid biosynthesis modification suggested high pHu beef experienced greater oxidative stress.

Data Mining as a Tool to Infer Chicken Carcass and Meat Cut Quality from Autochthonous Genotypes

The present research aims to develop a carcass quality characterization methodology for minority chicken populations. The clustering patterns described across local chicken genotypes by the meat cuts from the carcass were evaluated via a comprehensive meta-analysis of ninety-one research documents published over the last 20 years. These documents characterized the meat quality of native chicken breeds. After the evaluation of their contents, thirty-nine variables were identified. Variables were sorted into eight clusters as follows; weight-related traits, water-holding capacity, colour-related traits, histological properties, texture-related traits, pH, content of flavour-related nucleotides, and gross nutrients. Multicollinearity analyses (VIF ≤ 5) were run to discard redundancies. Chicken sex, firmness, chewiness, L* meat 72 h post-mortem, a* meat 72 h post-mortem, b* meat 72 h post-mortem, and pH 72 h post-mortem were deemed redundant and discarded from the study. Data-mining chi-squared automatic interaction detection (CHAID)-based algorithms were used to develop a decision-tree-validated tool. Certain variables such as carcass/cut weight, pH, carcass yield, slaughter age, protein, cold weight, and L* meat reported a high explanatory potential. These outcomes act as a reference guide to be followed when designing studies of carcass quality-related traits in local native breeds and market commercialization strategies.

Supranutritional Supplementation of Vitamin E Influences Myoglobin Post-Translational Modifications in Postmortem Beef Longissimus Lumborum Muscle

Post-translational modifications (PTM) in myoglobin (Mb) can influence fresh meat color stability. Dietary supplementation of vitamin E improves beef color stability by delaying lipid oxidation–induced Mb oxidation and influences proteome profile of postmortem beef skeletal muscles. Nonetheless, the influence of vitamin E on Mb PTM in postmortem beef skeletal muscles has yet to be investigated. Therefore, the objective of the current study was to examine the effect of dietary vitamin E on Mb PTM in postmortem beef longissimus lumborum muscle. Beef longissimus lumborum muscle samples (24 h postmortem) were obtained from the carcasses of 9 vitamin E–supplemented (VITE; 1,000 IU vitamin E diet/heifer·d−1for 89 d) and 9 control (CONT; no supplemental vitamin E) heifers. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to separate Mb from other sarcoplasmic proteins of beef longissimus lumborum muscle. Tandem mass spectrometry identified multiple PTM (phosphorylation, acetylation, 4-hydroxynonenalalkylation, methylation, dimethylation, trimethylation, and carboxymethylation) in the protein bands (17 kDa) representing Mb. The amino acids susceptible to phosphorylation were threonine (T) and tyrosine (Y), whereas lysine (K) residues were prone to other PTM. The same sites of phosphorylation (T34, T67, Y103), carboxymethylation (K77, K78), and 4-hydroxynonenal alkylation (K77, K78, K79) were identified in Mb from CONT and VITE samples, indicating that these PTM were not influenced by the vitamin E supplementation in cattle. Nonetheless, differential occurrence of acetylation, methylation, dimethylation, and trimethylation were identified in Mb from CONT and VITE samples. Overall, a greater number of amino acids were modified in CONT than VITE, suggesting that the supplementation of vitamin E decreased thenumbers of post-translationally modified residues in Mb. Additionally, PTM at K87, K96, K98, and K102 were unique to CONT, whereas PTM at K118 were unique to VITE. These findings suggested that dietary supplementation of vitamin E in beef cattle might protect amino acid residues in Mb—especially those located spatially close to proximal histidine—from undergoing PTM, thereby improving Mb redox stability.

Inclusion of Grape Pomace in Finishing Cattle Diets: Carcass Traits, Meat Quality and Fatty Acid Composition

Because of its high content of polyphenolic compounds, dietary inclusion of grape pomace (GP) in finishing cattle diet could possibly enhance product quality and the health value of beef lipids. Therefore, the aim of this study was to evaluate the effects of feeding a high amount of grape pomace in finishing cattle diets on carcass traits, product quality, and fatty acid (FA) composition of beef. Jersey × Holstein crosses (n = 24) were fed either a typical finishing diet (CON) or a finishing diet containing 58% grape pomace (DM basis; HGP). Following the feeding period, animals were harvested, and carcass traits measured. Longissimus lumborum (LL) and semimembranosus (SM) muscle were then collected from each carcass for sensory quality evaluation and FA profile analysis. Hot carcass weight, backfat thickness, and preliminary and final yield grades were greater (p ≤ 0.04) for CON than HGP steers. However, there was no diet effect on rib eye area (REA), kidney, pelvic, and heart (KPH) fat, and marbling. Feeding the HGP compared to CON diet reduced lipid oxidation of LL and SM steaks over time; the malondialdehyde (MDA) concentration, which did not differ on d 0 and 2 of 8-d simulated retail display, was lower on d 4, 6 and 8 for HGP than CON steers (treatment × day of simulated display interaction; p < 0.01). Brightness (L* values) and redness (b*) were greater for LL steaks from HGP than CON steers on most days of simulated display (treatment × day of simulated display interaction; p < 0.01). In addition, the LL and SM muscle content of several FA linked to positive health outcomes in humans including 18:2 n-6, 18:2 c9t11, total conjugated linoleic acid (CLA) and total polyunsaturated fatty acid (PUFA) was also greater (p ≤ 0.02) for steers fed the HGP compared to the CON diet. In summary, current findings suggest that although it could possibly limit growth performance, feeding a high amount of grape pomace to finishing cattle could enhance both the sensory quality and the health value of beef lipids, which are key in increasing consumer acceptability of beef.

Growth Performance, Carcass and Meat Traits of Autochthonous Arouquesa Weaners Raised on Traditional and Improved Feeding Systems

Arouquesa is an autochthonous bovine breed known for its Arouquesa PDO beef labeling. There are several production systems under the definition of PDO labeling. This study aimed to compare the effect of different production systems on carcass and meat traits for the Arouquesa breed. Two trials differing in diet and weaning age were conducted. The first trial included a TF group fed the traditional way and weaned at 9 months; a TF + S1 group, equal to TF, but with a starter supplement; and finally, a S1 + S2 group that was fed with a starter and a growth supplement and weaned at 5 months. The second trial was composed of a TF + S3 group fed like the TF + S1 group but reared until 12 months with a finishing supplement, and finally, the S3 group fed like the S1 + S2 group but reared until 12 months. In the first trial, the TF + S1 and S1 + S2 groups showed higher final live weight and average daily gain. In the second trial, we observed differences in the subcutaneous fat that was higher in the S3 group. Regarding meat traits, we observed differences in exudative and cooking losses in the first trial. In general, supplementation improved meat production without affecting meat quality parameters.

Effects of intramuscular fat on meat quality and its regulation mechanism in Tan sheep

Intramuscular fat (IMF) contributes importantly to various aspects of meat quality, and genetic regulation is an effective pathway to improve IMF deposition in sheep. In this study, we systematically explored the effect of IMF content on meat quality in Tan sheep and investigated the regulatory mechanism of flavor precursors metabolism and IMF deposition. The results revealed that IMF significantly affected meat color, total muscle fiber numbers, and muscle fiber types in Tan sheep. Widely-targeted metabolomic analysis showed that amino acids were the main differential flavor precursors between lambs with different IMF content. Importantly, the comparison of fatty acid profiles revealed that saturated fatty acids and monounsaturated fatty acids are beneficial for IMF deposition. Furthermore, integrated analysis between metabolome and transcriptome indicated that MME is a key gene resulting in the reduction of amino acids in lambs with high IMF content; and the joint analysis between fatty acid profiles and transcript profiles showed that ADIPOQ, FABP4, PLIN1, PPARGC1A, SLC2A1 accelerated IMF deposition through positive regulation of saturated fatty acids and monounsaturated fatty acids metabolism. These results revealed key changes in meat quality affected by IMF content and the corresponding genetic mechanism, which may provide a new insight for understanding the IMF differential deposition and for improving meat quality in Tan sheep.

Physical meat quality characteristics of Angolan giraffe (Giraffa giraffa angolensis) as affected by sex and muscle

Giraffe numbers grow exponentially when farmed, necessitating periodic culling. This study quantified the effect of sex and muscle on the physical quality characteristics of eight giraffe muscles. The Warner-Bratzler shear force (WBSF) was the only parameter to be affected by an interaction between sex and muscle (P < 0.001), although the interaction for the CIE L* values tended towards significance (P = 0.054). Cooking loss (male = 41.6 ± 0.35%; female = 40.7 ± 0.33%; P = 0.024) and CIE L* values (male = 38.8 ± 0.23; female = 37.3 ± 0.27; P = 0.039) were both affected by sex. Muscle had an effect on all physical parameters. The ultimate pH of all muscles was 5.5-5.9; the average WBSF of <43 N for all muscles indicates giraffe meat in this study is tender. This study shows that yield and physical characteristics of giraffe meat are favourable, and the results may be useful for the marketing of giraffe meat.

Consumer Perception of Beef Quality and How to Control, Improve and Predict It? Focus on Eating Quality

Quality refers to the characteristics of products that meet the demands and expectations of the end users. Beef quality is a convergence between product characteristics on one hand and consumers’ experiences and demands on the other. This paper reviews the formation of consumer beef quality perception, the main factors determining beef sensory quality, and how to measure and predict beef eating quality at scientific and industrial levels. Beef quality is of paramount importance to consumers since consumer perception of quality determines the decision to purchase and repeat the purchase. Consumer perception of beef quality undergoes a multi-step process at the time of purchase and consumption in order to achieve an overall value assessment. Beef quality perception is determined by a set of quality attributes, including intrinsic (appearance, safety, technological, sensory and nutritional characteristics, convenience) and extrinsic (price, image, livestock farming systems, commercial strategy, etc.) quality traits. The beef eating qualities that are the most valued by consumers are highly variable and depend mainly on the composition and characteristics of the original muscle and the post-mortem processes involved in the conversion of muscle into meat, the mechanisms of which are summarized in this review. Furthermore, in order to guarantee good quality beef for consumers in advance, the prediction of beef quality by combining different traits in scenarios where the animal, carcass, and muscle cuts can be evaluated is also discussed in the current review.

Chevon production and quality of Kalahari Red goats fed increasing levels of hempseed cake substituted for soybean meal

A 42-d study was conducted to evaluate the effects of replacing soybean meal with increasing levels of hempseed cake (HSC) in goat finishing diets on growth performance, carcass and chevon quality attributes. Thirty-five, 3-month-old Kalahari Red wethers (25 ± 1.5 kg initial body weight) were randomly allocated to one of five dietary treatments with seven animals per treatment. Wethers were fed maize-lucerne based finishing diets with inclusions of 0 (control), 25, 50, 75 and 100 g/kg DM of HSC replacing soybean meal as the main protein source. Diet had no effect (P > 0.05) on daily feed intake, average daily gain, final body weight and income-over-feed costs. Carcass and meat quality attributes were not influenced (P > 0.05) by HSC, except intramuscular fat, which increased linearly (P ≤ 0.05) with HSC inclusion levels. It was concluded that HSC could completely replace soybean meal in goat finishing diets without affecting chevon production and quality.

The Impact of Premortality Stress on Some Quality Parameters of Roe Deer, Wild Boar, and Red Deer Meat

The specifics of meat production from free-ranging animals include the killing of animals in the wild with firearms. This type of uncontrolled killing sometimes leads to the phenomenon that the game does not die immediately but after a certain time from the shot to death, which may ultimately affect the quality of the meat. During one hunting year on free-ranging red deer (Cervus elaphus) (RD), roe deer (Capreolus capreolus) (RoD), and wild boar (Sus scrofa) (WB), the effect of time from shot to death on final pH, water-holding capacity (WHC), water content, and colour (L*, a*, b*) was investigated. All analyses were performed on Musculus biceps femoris (BF). After shooting, the animals were divided into two categories (A = time from shot to death ≤ 1 min; B = time from shot to death > 1 min). In RD, group B had significantly lower (p < 0.05) water content. In RoD, group B had significantly lower (p < 0.05) values of L* and b*. In WB, group B had significantly lower (p < 0.05) L* value and significantly higher (p < 0.05) pH value. The study proves that in BF of the three studied game species, the time extension from shot to death significantly affects the final water content values in RD, L* and b* in RoD and pH and L * in WB.

Ultrasound as a Potential Technology to Improve the Quality of Meat Produced from a Mexican Autochthonous Bovine Breed

The objective of this study was to evaluate the effect of high-intensity ultrasound (HIU) on the physicochemical and textural properties of meat from Rararumi Criollo, a Mexican autochthonous bovine breed. After slaughter, Longissimus dorsi and Triceps brachii muscles were separated from carcasses, cut into 2.5 cm slices and treated with HIU, except the control group, which was not sonicated. After treatment, samples were vacuum-sealed and stored at 4 °C for 0, 3, 6, 9, 12 and 15 d. HIU increased (p < 0.05) the luminosity and yellowness (b*) of meat. Higher b* (p < 0.05) was observed in L. dorsi than in T. brachii muscles. No effect (p > 0.05) of HIU was detected on drip loss, pH, the water holding capacity and the total collagen of meat. The shear force of HIU-treated meat was lower (p < 0.05) than control samples, indicating a tenderizing effect. There were differences between muscles. L. dorsi was more tender (p < 0.05), and it had higher pH and WHC values than T. brachii. Overall, HIU is a potential method for tenderizing Raramuri Criollo cattle meat without negative impacts on other quality characteristics. HIU is an emerging technology that could add value to indigenous breeds and provide a new opportunity for the growing meat market.

Housekeeping Proteins in Meat Quality Research: Are They Reliable Markers for Internal Controls in Western Blot? A Mini Review

Advancements in technology and analytical methods enable researchers to explore the biochemical events that cause variation in meat quality. Among those, western blot techniques have been successfully used in identifying and quantifying the key proteins that have critical functions in the development of meat quality. Housekeeping proteins, like β-actin, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), and tubulins are often used as internal controls in western blots to normalize the abundance of the protein of interest. However, there are increasing concerns about using housekeeping proteins for western blot normalization, as these proteins do not demonstrate any loading differences above the relatively small total protein loading amounts of 10μg. In addition, the interaction between these housekeeping proteins and programmed cell death processes highlights the concerns about using the housekeeping protein as the internal control in meat quality research. Moreover, recent proteomic research has indicated that the abundance of some housekeeping proteins, like β-actin, GAPDH, and tubulin, can be altered by preslaughter stress, dietary supplementation, sex, slaughter method, genotype, breed, aging period, muscle type, and muscle portion. Furthermore, these housekeeping proteins could have differential expression in meat with differing color stability, tenderness, and water holding capacity. Therefore, this review aims to examine the realities of using housekeeping proteins as the loading control in meat quality research and introduce some alternative methods that can be used for western blot normalization.

Pulmonary arterial pressure in fattened Angus steers at moderate altitude influences early postmortem mitochondria functionality and meat color during retail display

Pulmonary hypertension is a noninfectious disease of cattle at altitudes > 1524 m (5,000 ft). Mean pulmonary arterial pressures (PAP) are used as an indicator for pulmonary hypertension in cattle. High PAP cattle (≥50 mmHg) entering the feedlot at moderate elevations have lower feed efficiency as compared to low PAP cattle (< 50 mmHg). The impact of pulmonary arterial pressure on mitochondrial function, oxidative phosphorylation (OXPHOS) protein abundance, and meat color was examined using longissimus lumborum (LL) from high (98 ± 13 mmHg; n = 5) and low (41 ± 3 mmHg; n = 6) PAP fattened Angus steers (live weight of 588 ± 38 kg) during early postmortem period (2 and 48 h) and retail display (days 1 to 9), respectively. High PAP muscle had greater (P = 0.013) OXPHOS-linked respiration and proton leak-associated respiration than low PAP muscles at 2 h postmortem but rapidly declined to be similar (P = 0.145) to low PAP muscle by 48 h postmortem. OXPHOS protein expression was higher (P = 0.045) in low PAP than high PAP muscle. During retail display, redness, chroma, hue, ratio of reflectance at 630 and 580 nm, and metmyoglobin reducing activity decreased faster (P < 0.05) in high PAP steaks than low PAP. Lipid oxidation significantly increased (P < 0.05) in high PAP steaks but not (P > 0.05) in low PAP. The results indicated that high PAP caused a lower OXPHOS efficiency and greater fuel oxidation rates under conditions of low ATP demand in premortem beef LL muscle; this could explain the lower feed efficiency in high PAP feedlot cattle compared to low PAP counterparts. Mitochondrial integral function (membrane integrity or/and protein function) declined faster in high PAP than low PAP muscle at early postmortem. LL steaks from high PAP animals had lower color stability than those from the low PAP animals during simulated retail display, which could be partially attributed to the loss of muscle mitochondrial function at early postmortem by ROS damage in high PAP muscle.

Impact of frozen storage on oxidation changes of some components in goose meat

The objective of this study was to investigate the oxidation activity and lipid oxidation changes in breast (BM) and leg (LM) muscles from 17-wk-old female White Kołuda geese packaged in a vacuum, and stored in freezing conditions at −20°C. The geese were fed ad libitum during the experimental period (up to 17 wk) on the same complete feed. The samples of LM (n = 18) and BM (n = 18) from the right carcass were stored for 30, 90, 80, 270, and 365 d. Lipid oxidation was described by determining changes in: TBARS value expressing the amount of malondialdehyde (MDA), total antioxidant capacity (TAC) measured by DPPH and ABTS methods and total reduction potential (TRP) measured by FRAP method. Moreover, total heam pigments pigment (THP), relative concentration of myoglobin (Mb), oxymyoglobin (MbO₂), and metmyoglobin (MMb) were determined in this study. Time of storage affected the TAC, TRP, TBARS, and the color stability of BM and LM. The THP concentration and Mb proportion decrease gradually during the 365 d of frozen storage, while the relative concentration of MMb increase in BM and LM. It was noted that the shares of MMb in both analyzed types of muscles stored for 365 d did not exceed 0.4. This value is considered to be the limit, after which the meat takes on an intense gray-brown color not accepted by the consumer. The oxidation processes occurring during frozen storage caused an increase of TBARS and a decrease of DPPH^•, ABTS^•+, FRAP values in both kinds of muscles. The amounts of TBARS during frozen storage of muscles did not exceed 2.0 mg MDA/kg of meat. A higher value of TBARS than 2.0 causes a lack of acceptance by consumers of the flavor profile. Based on the results concerning changes in the heam pigments, as well as changes related to the oxidation of lipids, we cannot unequivocally state in which types of muscles the changes had a more intense course.

Morphological signs of myopathy in pork that show no drastic decrease in pH after slaughter

High pH value 45 minutes after slaughter (рН45) has so far been the most frequently used indicator to select pig carcasses with normal course of autolysis. However, in practice, this does not provide meat quality homogeneity. Therefore, carcasses with рН45 > 6.0 were examined for signs of myopathy, which are characteristic for PSE meat, using the histological method. To perform the study, we randomly selected 320 individuals for slaughter out of 1,059 individuals of mixed swine grown in the same conditions. After slaughter, we selected 18 fresh carcasses that demonstrated low рН45. The results of the examination of the muscular tissue (L. dorsi) samples revealed that pork varied in microstructural characteristics. Only 44% of the samples had no signs of myopathy: no contracture nodes and destructive changes in the muscle fibers were present. A total of 39% of the samples were identified to the muscular tissue with mildly expressed myopathy, 17% of the samples – to the muscular tissue with acute myopathy. Thus, among the carcasses with рН45 > 6.0, 56% of the carcasses had signs of mild and acute myopathy, which explains quality homogeneity of meat selected using this criterion. Statistical analysis of the results suggested that the increase in the diameter of the muscle fibers of glycolytic type was related to appearance of signs of mild and acute myopathy – “giant fibers”. Increase in the weight of animals is not a risk factor. The obtained results allowed us to conclude the necessity of developing new approaches to assessing meat quality immediately after the slaughter with the purpose of increasing efficiency in predicting technological properties of meat. Promising directions of developing quick methods in histology allow us to hope that such approaches may be based on the data on microstructure of fresh muscular tissue.

Phenotypic and genetic correlations of pork myoglobin content with meat colour and other traits in an eight breed-crossed heterogeneous population

Meat colour is one of the most important meat quality traits affecting consumption desire. Genetic improvement for meat colour traits is not so easy because pigs can be phenotyped only after slaughter. Besides the parameters from the optical instrument, other indexes that reflect the material basis of meat colour should be measured accurately and used in the genomic analysis. Myoglobin (Mb) is the main chemical component determining meat colour. However, to what extent the Mb content contributes to meat colour, and whether it can be used as a trait for pig breeding to improve meat colour, and the correlations of Mb content with complex porcine traits are largely unknown. To address these questions, we measured the muscle Mb content in 624 pigs from the 7th generation of a specially designed eight breed-crossed pig heterogeneous population, evaluated its phenotypic and genetic correlations with longissimus thoracis colour score at 24 h after slaughter. More than that, we also systematically phenotyped more than 100 traits on these animals to evaluate the potential correlations between muscle Mb content and economically important traits. Our results showed that the average muscle Mb content in the 624 pigs was 1.00 mg/g, ranging from 0.51 to 2.17 mg/g. We found that higher Mb content usually correlated with favourable meat colour, higher marbling score, less moisture content, and less drip loss. Genetic correlation analysis between muscle Mb content and 101 traits measured in this study shows that Mb content is also significantly correlated with 31 traits, including marbling, shear force, firmness, and juiciness. To our knowledge, this is one of the largest studies about the correlations of muscle Mb content with as many as 100 various traits in a large-scale genetically diversified population. Our results showed that the Mb content could be a selection parameter for the genetic improvement of meat colour. The selection for higher Mb content will also benefit marbling, shear force, firmness, and overall liking but might not affect the growth, carcass, and fat deposition traits.

Carcass Yields and Physical-Chemical Meat Quality Characteristics of Namibian Red Hartebeest (Alcelaphus buselaphus) as Influenced by Sex and Muscle

This study determined the carcass yields of red hartebeest from Namibia and compared the physical-chemical meat quality characteristics of six different muscles (biceps femoris, infraspinatus, longissimus thoracis et lumborum, semimembranosus, semitendinosus, and supraspinatus) for both males and females. Red hartebeest males were heavier (133.92 kg) than females (114.20 kg) but the average dressing percentage did not differ between the two sexes. Muscles from females had a lower mean shear force value of 3.59 kg/1.27 cm ø, compared to males (4.23 kg/1.27 cm ø). The most tender muscle was the infraspinatus of the female treatment group, while the semimembranosus of the male treatment group was the least tender muscle. Drip loss, cooking loss and L* (lightness) values were not affected by sex. The largest hue angle was observed in the semitendinosus muscle of the female treatment group (28.94°), and it was thus the lightest red muscle. The highest chroma values (17.3) were observed in the semimembranosus muscle. Muscle protein content averaged 20.5% over all treatment combinations, and the mean intra-muscular fat content for both male and female muscles was low (2.4%). The shoulder muscles, infraspinatus and supraspinatus, of the females had the highest fat content (2.7%). The results indicate that red hartebeest meat should be market according to specific muscles and that sex of the animals need not be considered during marketing.

Hierarchical clustering as a tool to develop a classification scheme for rabbit meat quality

<p>This study aimed to characterise the quality of meat from commercially-raised rabbits. Animals came from five different producers and were  laughtered in three different plants under provincial or federal inspection jurisdiction. Animal behaviour evaluated by scan sampling prior to feed withdrawal (FW) and transport, as well as blood lactate concentration at exsanguination, did not raise concerns with respect to stress. Stomach pH was higher (<em>P</em>=0.047) when the FW time was short (≤13.5 h), at a mean value of 2.23. All pH values measured 1 h post-mortem from the Biceps femoris (BF) and almost all (97.6%) from the Longissimus lumborum (LL) were higher than 6. Values for ultimate pH measured 24 h postmortem(pH_u) ranged from 5.80 to 6.83 and from 5.70 to 6.70 for BF and LL muscles, respectively. The maximum meat drip loss recorded was 2.6%, while cooking loss reached 30%. Meat lightness (L*) and colour intensity (C*) for the long FW times (≥23 h) were no different from those with short and intermediate (15.5 to 17.3 h) FW times. However, these colour parameters were higher for the short FW time class compared to the intermediate FW time class (<em>P</em>&lt;0.02). A hierarchical cluster analysis based on pH_u, cooking loss and lightness (L*) from 200 rabbit loins was performed. Of the four clusters created, clusters 1 and 2 had the best and second-best meat quality, respectively. Clusters 3 and 4 had the lowest meat quality and presented DFD-like (dark, firm and dry) characteristics. Meat did not exhibit PSE-like (pale, soft, exudative) characteristics, even for the slaughter lot with the minimum mean pH_u. Of the eight slaughter lots evaluated, more than 50% of the meat from three of them fell into clusters 3 and 4; all three were in the intermediate FW time class. Overall, the quality of rabbit meat analysed was acceptable for commercial use, but rather variable. This suggests that there are factors within the value chain that are not yet fully controlled and require further investigation.</p>

Effect of Wet Aging on Color Stability, Tenderness, and Sensory Attributes of Longissimus lumborum and Gluteus medius Muscles from Water Buffalo Bulls

Simple Summary

The water buffalo is found in many tropical countries worldwide. In the current world scenario, where meeting the protein requirements of the population is one of the biggest future challenges, buffalo meat could be a good source of protein and other nutrients. Currently, very little information is available regarding buffalo meat quality attributes. Therefore, this study was designed to evaluate the effects of aging time and muscle type on meat quality attributes (pH, color, tenderness, water holding capacity, and sensory acceptance) of buffalo meat. The results showed that color, tenderness, and sensory attributes were improved with aging time; the suitable aging time required to enhance meat quality attributes in Longissimus lumborum and Gluteus medius muscles is 28 and 21 days, respectively.

Abstract

The present study aimed to investigate the effect of wet aging on meat quality characteristics of Longissimus lumborum (LL) and Gluteus medius (GM) muscles of buffalo bulls. Meat samples from six aging periods, i.e., 0 day (d) = control, 7 d, 14 d, 21 d, 28 d, and 35 d, were evaluated for pH, color, metmyoglobin content (MetMb%), cooking loss, water holding capacity (WHC), myofibrillar fragmentation index (MFI), Warner–Bratzler shear force (WBSF), and sensory evaluation. The pH, instrumental color redness (a *), yellowness (b *), chroma (C *), and MetMb% values were increased, while the lightness (L *) and hue angle (h *) values showed non-significant (p > 0.05) differences in both LL and GM muscles in all aging periods. The cooking loss increased while WHC decreased till 35 days of aging. MFI values significantly (p < 0.05) increased, while WBSF values decreased; in addition, sensory characteristics were improved with the increase in the aging period. Overall, the color, tenderness, and sensory characteristics were improved in LL and GM muscles until 28 and 21 days of aging, respectively. Based on the evaluated meat characteristics, 28 days of aging is required to improve the meat quality characteristics of LL, whereas 21 days of aging is suitable for GM muscle.

Myoglobin Post-Translational Modifications Influence Color Stability of Beef Longissimus Lumborum

Post-translational modifications (PTM) of proteins play critical roles in biological processes. PTM of muscle proteins influence meat quality. Nonetheless, myoglobin (Mb) PTM and their impact on fresh beef color stability have not been characterized yet. Therefore, our objectives were to identify Mb PTM in beef longissimus lumborum muscle during postmortem aging and to characterize their influence on color stability. The longissimus lumborum muscles from 9 (n = 9) beef carcasses (24 h postmortem) were subjected to wet aging for 0, 7, 14, and 21 d. At the end of each wet-aging period, steaks were fabricated. One steak for analyses of PTM was immediately frozen at −80°C, whereas other steaks were assigned to refrigerated storage in the darkness under aerobic packaging. Instrumental color and biochemical attributes were evaluated on day 0, 3, or 6 of storage. Mb PTM were analyzed using two-dimensional electrophoresis and tandem mass spectrometry. Surface redness (a* value), color stability, and Mb concentration decreased (P &lt; 0.05) upon aging. Gel image analyses identified 6 Mb spots with similar molecular weight (17 kDa) but different isoelectric pH. Tandem mass spectrometry identified multiple PTM (phosphorylation, methylation, carboxymethylation, acetylation, and 4-hydroxynonenal alkylation) in these 6 isoforms. The amino acids susceptible to phosphorylation were serine (S), threonine (T), and tyrosine, whereas other PTM were detected in lysine (K), arginine (R), and histidine residues. Additionally, distal histidine (position 64), critical to heme stability, was found to be alkylated. Overall, Mb PTM increased with aging. The aging-induced PTM, especially those occurring close to hydrophobic heme pocket, could disrupt Mb tertiary structure, influence heme affinity, and compromise oxygen binding capacity, leading to decreased color stability of fresh beef. Furthermore, PTM at K45, K47, and K87 were unique to Mb from non-aged beef, whereas PTM at R31, T51, K96, K98, S121, R139, and K147 were unique to Mb from aged counterparts, indicating that these Mb PTM could be used as novel biomarkers for fresh beef color stability.

Principal component analysis of lipid and protein oxidation products and their impact on color stability in bison longissimus lumborum and psoas major muscles

The study aims were to compare lipid (malondialdehyde [MDA], 4-hydroxy-2-nonenal [HNE]) and protein (carbonyl content [CAR]) oxidation products between two bison muscles (longissimus lumborum [LL] and psoas major [PM]) at different aging and retail display time and determine their influence on muscle color stability. Regardless of the aging and retail display time, LL showed greater redness (a* value; P = 0.04) and lower surface discoloration (P < 0.01) than PM as well as LL exhibited lower MDA, HNE, and CAR content compared to PM (P < 0.05). In both muscles, MDA showed the highest correlation to a* (r = -0.78; P < 0.01) and discoloration (rs = 0.82; P < 0.01) scores, particularly in PM muscle compared to LL muscle. In conclusion, the principal component analysis revealed 4 distinct color deterioration clusters within steaks displayed at d 4 according to the muscle and aging time, and MDA critically influences color deterioration patterns in bison muscles.

Broiler responses to ferrous sulfate at different time periods: a comprehensive research on qualitative parameters of breast meat

The objective of present study was to study the effects of dietary ferrous sulfate (FeSO4) and time periods on Fe deposition, nutrients composition, color indices, water-holding capacity and oxidative stability of breast meat in broilers. This experiment was performed by 450 broilers in a 3 × 3 factorial design with 3 levels of supplemental Fe (0, 40 and 80 mg/kg) and 3 time periods (total, T: from 1 to 42 days; grower and finisher, GF: from 11 to 42 days and finisher, F: from 25 to 42 days). The results showed that increasing the iron supplementation to 80 mg/kg increased the breast meat crude Protein. Adding 80 mg/kg of FeSO4 during the T period increased the iron content of breast meat compared to other dietary periods. Supplementation of 40 mg/kg FeSO4 during T and GF periods increased quadratically (P < 0.001) the L* value of meat compared to F period. Meat redness significantly increased by adding of 80 mg/kg iron into broiler diet. At 1 and 7 day postmortem, malondialdehyde (MDA) and total antioxidant capacity (T-AOC) of meat were measured for determination of lipid oxidation stability of tissue. Feeding 40 mg/kg Fe caused a higher MDA value at both time points compared to 0 mg/kg Fe (linear response). However, increasing the Fe level to 80 mg/kg decreased MDA of meat (quadratic response). Adding 40 mg/kg Fe increased T-AOC of meat at both time points. It was concluded that dietary supplementation of 80 mg/kg Fe during T period resulted in the higher Fe deposition and better oxidative stability of breast meat in broilers.

Replacement of Sodium Tripolyphosphate with Iota Carrageenan in the Formulation of Restructured Ostrich Ham

The influence of iota carrageenan (iota-CGN) as a partial replacement of sodium tripolyphosphate (STPP) was investigated on the physical (pH, yield, instrumental color, texture profile analysis), chemical (moisture, protein, total fat, ash, phosphate) and sensory (descriptive analysis, acceptance testing) quality of restructured ostrich ham (95% lean meat plus fat). Treatments consisted of five decreasing levels of STPP (0.70%, 0.53%, 0.35%, 0.18% and 0%) that were simultaneously substituted with five increasing levels of iota-CGN (0%, 0.1%, 0.2%, 0.3% and 0.4%). Cooked yield, hardness, cohesiveness, and gumminess of restructured ostrich ham increased (p ≤ 0.05) with decreasing levels of STPP (and increased levels of iota-CGN). No significant trend in instrumental color measurements or springiness were observed between treatments. Ostrich ham with 0.35% STPP and lower had increased ostrich meat aroma and flavor, while spicy aroma and flavor, mealiness and consumer acceptance decreased. Iota carrageenan can be substituted for STPP (up to 0.35% STPP and 0.2% iota-CGN) to produce reduced STPP ham.

Meat quality characteristics of lot-fed Australian Rangeland goats are unaffected by live weight at slaughter

The effects of live weight on carcass characteristics and meat quality of Australian Rangeland goats were determined. Fifty-two intact-male kid goats were fed Mitchell grass hay and finisher pellets ad libitum for 42 days. Prior to slaughter, kids were categorised into live weight groups: 'Heavy' (≈33.1 kg) or 'Light' ≈ 24.3 kg). Fifteen kids per group were randomly selected, slaughtered and carcass characteristics measured. The longissimus lumborum (LL) and the biceps femoris (BF) muscles were removed for quality measurements. The Heavy group had higher dressing, hindquarters, non-carcass component and offal percentages (P < 0.05). Live weight had no effect on proportion of carcass cuts, muscle meat colour, cooking loss, Warner-Bratzler shear force, total fat or ash (P > 0.05), but influenced the moisture and protein content in the LL and the moisture content in the BF (P < 0.05). The findings suggest that live weight of entire male Rangeland goats had no effect on meat quality characteristics.

Effects of protein posttranslational modifications on meat quality: A review

Meat quality plays an important role in the purchase decision of consumers, affecting producers and retailers. The formation mechanisms determining meat quality are intricate, as several endogenous and exogenous factors contribute during antemortem and postmortem periods. Abundant research has been performed on meat quality; however, unexpected variation in meat quality remains an issue in the meat industry. Protein posttranslational modifications (PTMs) regulate structures and functions of proteins in living tissues, and recent reports confirmed their importance in meat quality. The objective of this review was to provide a summary of the research on the effects of PTMs on meat quality. The effects of four common PTMs, namely, protein phosphorylation, acetylation, S-nitrosylation, and ubiquitination, on meat quality were discussed, with emphasis on the effects of protein phosphorylation on meat tenderness, color, and water holding capacity. The mechanisms and factors that may affect the function of protein phosphorylation are also discussed. The current research confirms that meat quality traits are regulated by multiple PTMs. Cross talk between different PTMs and interactions of PTMs with postmortem biochemical processes need to be explored to improve our understanding on factors affecting meat quality.

A comprehensive insight into the effects of microbial spoilage, myoglobin autoxidation, lipid oxidation, and protein oxidation on the discoloration of rabbit meat during retail display

The effects of the retail display temperature (8 °C, 3 °C and - 1 °C) on the discoloration of the Longissimus thoracis et lumborum of rabbits and the associations among such effects with microbial spoilage, myoglobin autoxidation, lipid oxidation, and protein oxidation were investigated. The total aerobic count, total volatile basic nitrogen content, metmyoglobin content, protein carbonyl content, and contents of thiobarbituric acid-reactive substances steadily increased during retail display. Moreover, the lightness and redness of the rabbit meat significantly (P < 0.05) declined over time, whereas the yellowness increased considerably (P < 0.05) with prolonged retail time. Canonical correlation analysis suggested that microbial spoilage, myoglobin autoxidation, lipid oxidation, and protein oxidation jointly affected rabbit meat color. Linear mixed models further revealed that microbial spoilage, myoglobin autoxidation, lipid oxidation and protein oxidation positively affected yellowness, and they inversely impacted lightness and redness.

Effect of Different Combinations of Freezing and Thawing Rates on the Shelf-Life and Oxidative Stability of Ostrich Moon Steaks (M. Femorotibialis medius) under Retail Display Conditions

The aim of this study was to investigate the interaction between different rates of freezing and thawing on whole ostrich moon steaks to establish a combination or singular main effect that minimises thaw loss and maximises the retail display shelf-life regarding moisture loss, colour, lipid oxidation and tenderness. Five characteristic freezing rates (FR: 1, 2, 4, 8, 24 h) were compared with five characteristic thawing rates (TR: 1.5, 3, 6.5, 14, 21 h) in a completely randomised block design. Moon steaks (M. femorotibialis medius) from 125 birds were randomly assigned to a specific treatment combination before being subjected (after thawing) to a 10-day chilled storage at 4 °C shelf-life trial. Thawing rate had no effect (p > 0.05) on any of the quality (colour, drip and cooking losses, shear force, 2-thiobarbituric acid (TBARS)) parameters whilst freezing rate and display time both had significant (p < 0.05) influences. Thaw loss was lowest (p < 0.05) for the FR_1h and FR_2h, followed by FR_4h, FR_8h and FR_24. The FR_1h had the highest (p < 0.05) drip and shear force values during display while the FR_2h and FR_8h had the highest rate of oxidation (TBARS and metmyoglobin formation). FR_24h had the second best (p < 0.05) colour retention after FR_4h and minimal package drip. Overall, FR_4h resulted in the best quality meat over the entire shelf-life with high bloom retention, low TBARS and shear force, and average thaw, drip and cooking loss.

The effect of dietary Marula nut meal on the physical properties, proximate and fatty acid content of Japanese quail meat

Soyabean meal (SBM) is the major dietary protein source for the poultry industry in sub-Saharan Africa. Due to inadequate local soyabean production, alternative protein sources are required. Two hundred 9-day old Japanese quail chicks were randomly allocated to grower diets wherein Marula nut meal (MNM) substituted SBM on a crude protein (CP) basis at 0%, 25%, 50%, 75% and 100% and fed for 4 weeks, followed by being fed on similarly formulated finisher diets for 2 weeks, and thereafter they were humanely slaughtered and dressed. Initial pH (pH_i) and ultimate (pH_u), colour, thawing loss (TL), cooking loss (CL), tenderness, proximate and fatty acid (FA) composition of the breast and thigh meat were determined. The results showed that pH_i and pH_u of meat from carcasses of quail fed diet 1 was lower, but had lighter and less red meat than that from counterparts fed diet 5 (P < 0.01). Dietary MNM had no effect (P>0.05) on TL, CL and tenderness of the meat. The ash content of the meat increased with an increase in dietary MNM, but its CP and fat decreased (P < 0.05). In addition, the total saturated FA content of meat from birds fed diet 4 was lower (P < 0.05) than other counterparts. Meat from birds fed diets 1 and 2 had a lower oleic acid (OA) content in comparison to meat from birds fed diets 3, 4 and 5. MNM can potentially be utilised in quail feeds without compromising the physical and proximate properties of the meat. Also, it can be used to produce lean but OA-rich meat with possible potential health benefits to consumers.

Effect of sex on carcass yield and meat quality of guinea pig

The aim of this study was to evaluate the effect of sex on carcass yield and meat quality of guinea pig (Cavia porcellus). Twenty animals (10 males and 10 females) Criollos, with initial body weight of 286 ± 4.26 g and 2 months of age were distributed in a completely randomized design. The guinea pigs fed a diet based on vegetables and concentrate in a roughage:concentrate ratio of 80:20. After 60 days, animals were slaughtered and their carcasses and meat were evaluated. Males had higher slaughter weight, total weight gain, hot carcass weight, cold carcass weight, cold carcass yield, meat weight, meat yield, leg weight, loin + flank weight and front weight (P < 0.05). Females showed higher carcass chilling loss, liver yield, cooking loss and protein and ash content in meat (P < 0.05). The use of male guinea pigs for meat production provides higher yields of carcasses, meat and commercial cuts, and lower losses during carcass chilling and meat cooking.

Recent Updates in Meat Color Research: Integrating Traditional and High-Throughput Approaches

Deviation from a bright cherry-red color of fresh meat results in less consumer acceptance and either discounted or discarded products in the value chain. Tissue homeostasis changes immediately after exsanguination, leading to acidification of muscle. Any alteration in pH drop can influence both muscle structure and enzymatic activity related to oxygen consumption and the redox state of myoglobin. This review focuses on both fundamental and applied approaches to under-stand the effects of pH on biochemical changes, oxygen diffusion, and its impact on meat color. Recent updates utilizing high-throughput “omics” approaches to elucidate the biochemical changes associated with high-pH meat are also dis-cussed. The fundamental aspects affecting fresh meat color are complex and highly interrelated with factors ranging from live animal production to preharvest environmental issues, muscle to meat conversion, and numerous facets along the merchandising chain of marketing meat to consumers.

Physical Changes during Post-Mortem Ageing of High-Value Impala (Aepyceros Melampus) Steaks

Antelope meat production is rapidly growing, not only due to their adaptation to marginal land usage, but also because of its favorable nutritional properties and free-range production. However, limited information is available on the meat quality and processing potential of game meat for commercial consumption. The objective of this study was to determine the ageing period to achieve maximum tenderness of longissimus thoracis et lumborum (LTL) muscles of impala. The LTL muscles of 11 male and 11 female impala were harvested, and divided into eight portions. Each portion was randomly allocated to 1, 2, 4, 6, 8, 10, 12, or 14 days of wet-ageing (4 °C) in vacuum packaging. The meat pH, color, weep loss, cooking loss, and Warner–Bratzler shear force were measured throughout ageing. Initially the ageing profile differed depending on the sex of the animal from which the muscle was harvested; however, after 8 days of ageing, maximum tenderness was reached (13.5 ± 0.91 N) and no further sex differences were seen. Ageing improved the surface color of all meat until day 8, after which discoloration occurred. Therefore, it is recommended that impala LTL steaks should be wet-aged at 4 °C for eight days to achieve maximum tenderness and minimize sex variability.

Effects of Feeding and Maturation System on Qualitative Characteristics of Buffalo Meat (Bubalus bubalis)

We aimed to evaluate the effects of post dry ageing (PDA) period on meat colour and rheological characteristics in 16 buffalo bulls fed two different diets: with (FRS) or without (CTL) rye grass. Animals were randomly divided into two feeding groups and slaughtered at 540 ± 4.7 and 533 ± 7.0 kg of live body weight, respectively, for the CTL and FRS group. After five days post-mortem ageing (T0), Semitendinosus muscle (ST) and Longissimus muscle (LD) underwent a prolonged maturation process in a controlled meat chamber for 30 days (ST) and until 60 days (LD). After 30 days (T1), significant changes (p < 0.01) in meat colour (ΔE) in both muscles of the FRS group was recorded, while no significant change was observed in CTL group. The FRS diet had a positive effect on textural properties of ST muscle compared to CTL diet, as well as hardness, chewiness and gumminess. All qualitative characteristics improved in the first period of PDA but, whereas LD showed to keep improving, extending the post-ageing period by further 30 days, the ST becomes un-processable at 60 days. In conclusion, a combined used of fresh feeding and PDA period could enhance both tenderness and colour in animal fed FSR.

Profile of Back Bacon Produced From the Common Warthog

The common warthog (Phacochoerus africanus) has historically been hunted and consumed by rural communities throughout its distribution range in Africa. This study aims to develop a processed product from warthog meat in the form of back bacon (Longissimus thoracis et lumborum) as a healthy alternative meat product and to determine its chemical and sensory characteristics derived from adult and juvenile boars and sows. The highest scored attributes included typical bacon and smoky aroma and flavor, and salty flavor, as well as tenderness and juiciness. Neither sex nor age influenced the bacon's chemical composition; the bacon was high in protein (~29%) and low in total fat (<2%). Palmitic (C16:0), stearic (C18:0), linoleic (C18:2ω6), oleic (C18:1ω9c), and arachidonic (C20:4ω6) were the dominant fatty acids. There was an interaction between sex and age for the PUFA:SFA ratio (p = 0.01). The differences between sex and age class are considered negligible regarding the overall profile and healthiness of the bacon.

Ante-and post-mortem strategies to improve the meat quality of high-value muscles harvested from farmed male common eland (Taurotragus oryx)

The effects of immunocastration, pelvic suspension and wet ageing on the meat quality of the longissimus lumborum et thoracis (LTL) and biceps femoris (BF) muscles of male common eland were evaluated. Ten subadult males were either immunocastrated (n = 5) or remained intact (n = 5) throughout a four-month growth trial, after which their carcass sides were randomly allocated to either pelvic- or Achilles-suspension. The LTL and BF were further aged for 14 days, measuring changes in the physical quality weekly. The sensory quality of the LTL and BF were determined after ageing (8/9 days, respectively). Immunocastration had minimal effects on the meat quality of male eland, but pelvic suspension decreased the shear force. All muscles reached minimum shear force after seven days of ageing, and the panellists ranked the pelvic-suspended muscles higher for tenderness traits. Incorporating pelvic suspension and wet ageing into the commercial processing of eland carcasses should be considered to improve overall meat quality.

Meat color is determined not only by chromatic heme pigments but also by the physical structure and achromatic light scattering properties of the muscle

Meat color is important for consumer acceptability, with excessively dark meat often associated with consumer rejection. It is determined chromatically by pigment content (measured by hue and chroma) and achromatically by scattering of light by the microstructure (measured by lightness), the latter of which has received minimal research focus. This review discusses the individual components of the meat microstructure that cause differences in achromatic contributions to color. Differences in achromatic light scattering between light and dark extremes of meat color are most likely explained by structural attributes within the muscle cell. These differences are proposed to arise from variations in (a) transverse shrinkage of the structural lattice of the myofilaments, myofibrils, and muscles fibers, (b) longitudinal shrinkage of the sarcomere, and (c) different protein composition of the surrounding medium (sarcoplasm and extracellular space). These are discussed at a mechanistic level, in relation to six parameters of the muscle cell: (a) protein surface charge altering the myofilament spacing, (b) protein solubility, (c) sarcoplasmic protein binding to myofilaments and myofibrils, (d) integrity of the cytoskeleton and cell adhesion proteins, (e) sarcomere integrity and myofibrillar proteins, and (f) myosin denaturation and rigor bond modification. New data are presented to support the proposed role of structural elements in muscle causing achromatic light scattering and their contribution to the surface color of meat. In addition, the relationships between lightness and water holding capacity and pH are explored and the economic impact of dark meat for the meat industry is discussed.

Carbon Chain Length of Lipid Oxidation Products Influence Lactate Dehydrogenase and NADH-Dependent Metmyoglobin Reductase Activity

The biochemical basis of lower metmyoglobin reducing activity (MRA) in high-oxygen modified atmospheric packaged (HiOx-MAP) beef than those in vacuum and polyvinyl chloride (PVC) packaging is not clear. To explore this, the effects of lipid oxidation products with varying carbon chain length on lactate dehydrogenase (LDH) and NADH-dependent metmyoglobin reductase activity were evaluated. Surface color, MRA, and lipid oxidation of beef longissimus lumborum steaks (n = 10) were measured during 6-day display. Further, two enzymes, LDH and NADH-dependent metmyoglobin reductase (n = 5), critical for MRA were incubated with or without (control) lipid oxidation products of varying carbon chain length: malondialdehyde (3-carbon), hexenal (6-carbon), and 4-hydroxynonenal (9-carbon). Steaks in HiOx-MAP had greater (P < 0.05) redness than vacuum and PVC, but had lower (P < 0.05) MRA and greater (P < 0.05) lipid oxidation on day 6. LDH and NADH-dependent metmyoglobin reductase activities were differentially influenced by lipid oxidation products (P < 0.05). The results indicate that the difference in reactivity of various lipid oxidation products on LDH (HNE > MDA = hexenal) and NADH-dependent metmyoglobin reductase (HNE = MDA > hexenal) activity could be responsible for lower MRA in HiOx-MAP.