Postmortem Aging Research Articles

Characteristics of volatile flavor development in aged longissimus lumborum post-ultrasound treatment: 4D proteomics combined with phosphoproteomics analysis

The present study aimed to evaluate the impact of ultrasonic treatment on the development of volatile flavor compounds in beef during postmortem aging and its potential mechanism. Results showed that ultrasound treatment may cause an increase in the total content of unsaturated fatty acids, which could lead to lipid oxidation and potentially result in changes in the flavor development. Additionally, it was also found that ultrasound exacerbated protein oxidation. A total of 141 volatile compounds were obtained by SPME–GC–MS analysis, and 18 differential aroma substances (P < 0.05, VIP > 1) were obtained by orthogonal partial least squares discrimination analysis (OPLS-DA). Five key volatile flavor compounds (hexanal, nonanal, octanal, pentanal, and 1-pentanol) originating from lipid oxidation were identified according to odor activity values (OAVs). The concentration of these compounds was significantly higher in the ultrasonic treatment group compared to the non-ultrasonic group that underwent a 3-day aging process. Nine common differentially expressed proteins (DEPs) were identified through the utilization of proteomics and phosphoproteomics analysis. KEGG pathways showed that selenocompound metabolism, tryptophan metabolism and cysteine and methionine metabolism led to flavor formation during wet aging of beef after ultrasound treatment. This study provided proteomic insights into the flavor of beef aged through sonication and suggested potential links between flavor development and biological processes.

Effects of preslaughter handling approach and aging on carcass and meat quality attributes in goats

This study aimed to assess the impact of preslaughter handling method and aging on carcass and meat quality traits in goats. Twenty-seven male goats of Ardi breed were assigned into three treatment groups viz., the control (C), ear pulling (EP), and hind-leg pulling (HP). The carcasses were stored for post-mortem aging periods of 1, 7, and 14 days. On day 0 and the respective aging days, samples of the Longissimus thoracic et lumborum (LTL) muscles were collected and examined for various meat quality parameters. The preslaughter handling of goats significantly increase the total bacterial count, total Enterobacteriaceae count, and total Clostridium count. It also had a significant effect on the pH of LTL muscle during aging. A significantly lower values for pH were recorded in the treatment groups (EP and HP) as compared to the pH of the C group on day 1 of aging. Notably, both treatment groups were found to increase the shear force, hardness, and chewiness of the meat, ultimately compromising its quality. The proper treatment of meat animals, especially goats, is crucial for enhancing carcass and meat quality. Careful preslaughter handling practices by avoiding ear and hind-leg pulling can minimize negative impacts on the final product. Therefore, the significance of conducting this study lies in its potential to enhance animal welfare, improve meat quality, boost economic benefits for producers, and foster consumer confidence in meat products.

Three-dimensional quantitative analysis of arterial bed and elements of pelvicalyceal system of kidneys in men

The aim of the study was to investigate the patterns of three-dimensional quantitative organization of the renal artery branches in relation to the elements of the renal pelvicalyceal system in men. The study was conducted on 58 corrosion preparations of arterial vessels and renal pelvicalyceal structures obtained from men with postmortem age intervals from 22 to 75 years. As a result of the morphological study, a spatial and quantitative characteristic was given to different variants of renal artery branching, with an emphasis on their transformation into secondary vascular branches classified as zonal arteries. Additionally, a detailed analysis of the topographic and anatomical relationship between the intraorgan arterial branches of the renal artery and the excretory segments of the kidney was carried out, which made it possible to clarify the features of their spatial organization. Knowledge of the spatial arrangement of the arterial branches of the kidney, which directly correlates with the variable features of its renal pelvicalyceal apparatus and excretory system segments, opens the way to predicting potential obstacles during surgical procedures, especially during nephrolithotomy.

The correlation between Smac, IAPs and mitochondrial apoptosis, muscle tenderness during postmortem aging of Oula Tibetan sheep meat

Oula Tibetan sheep meat has rich nutritional value but relatively poor tenderness. Recently, apoptosis of muscle cells has gradually become a research hotspot for improving meat tenderness during postmortem aging. Smac can promote the decrease of IAPs expression in tumor cells, thereby inducing mitochondrial apoptosis. However, the relationship between Smac, IAPs and mitochondrial apoptosis, muscle tenderness during postmortem meat aging is still unclear. Thus, the aim of this work was to explore the relationship between Smac, IAPs and mitochondrial apoptosis as well as muscle tenderness during postmortem meat aging. Smac concentration, IAPs concentration, pH value, ATP content, SDH activity, MPTP opening degree, MMP, caspase-3/9 activity, apoptotic rate, MFI and shear force value of Oula Tibetan sheep meat were measured at different aging times and correlation analysis was performed. Correlation analysis revealed that Smac, IAPs were markedly related to mitochondrial apoptosis and muscle tenderness during postmortem aging of Tibetan sheep meat. The results suggest that Smac may regulate IAPs to promote mitochondrial apoptosis and muscle tenderization in Oula Tibetan sheep meat during postmortem aging.

Unveils key proteins in Xinjiang goat muscle linked to post-mortem meat quality: A TMT-based proteomic analysis

An extensive proteomic analysis utilizing the tandem mass tag (TMT) method was conducted to investigate the changes in protein expression in the longissimus dorsi muscle of Xinjiang goats over various post-mortem intervals: immediately after death within 0 h, 12 h, 24 h and 48 h. The investigation carefully identified around 108 proteins that showed significant changes in expression during these intervals. Among these proteins, six were highlighted for their crucial roles in muscle growth and differentiation of muscle fibers post-mortem. These proteins, namely COL12A1, MRPL46, CTNNB1, MYH1, CAPZA1, and MYL9, have a direct effect on the meat's quality attributes, such as tenderness and color. Further discuss observed a progressive increase in the expression of proteins linked with oxidative metabolism (MSRB2, ENOX1, LOC102170282, GSTM1, and AOC3) as the post-mortem aging period extended, particularly between 24 h to 48 h. These proteins are instrumental in defining the color and flavor profiles of goat meat, underscoring the importance of precise processing and storage conditions to preserve meat quality during the critical aging phase. This enhanced understanding of protein expression dynamics offers significant implications for optimizing meat quality and provides a scientific basis for post-mortem handling practices in the goat meat industry.

Differential regulation of physicochemical properties and myofibrillar protein degradation of yak meat by interactions between reactive oxygen species and reactive nitrogen species during postmortem aging.

This study aimed to explore how interactions between reactive oxygen species (ROS) and reactive nitrogen species (RNS) affect oxidative properties, nitrosative properties, and myofibrillar protein degradation during postmortem aging of yak meat. Yak longissimus dorsi was incubated with saline, ROS activator (H2O2)/inhibitor N-Acetyl-L-cysteine (NAC) and RNS activator S-Nitrosoglutathione (GSNO)/inhibitor L-NAME hydrochloride (L-NAME) combined treatments at 4 °C for 12, 24, 72, 120, and 168 h. The results indicated that regardless of whether RNS was activated or inhibited, activated ROS played a dominant role in myofibrillar protein degradation by oxidative modification to increase carbonyl content, disulfide bonds, surface hydrophobicity, and dimerized tyrosine while decreasing sulfhydryl content, thereby degrading nebulin, titin, troponin-t and desmin. Notably, the Warner-Bratzler shear force (WBSF) of the H2O2 + L-NAME group was the smallest, whereas that of the NAC + GSNO group was smaller than that of the NAC + L-NAME group. These findings provide new insights into meat tenderization patterns through the interaction between ROS and RNS. © 2024 Society of Chemical Industry.

Lipidome and metabolome profiling of longissimus lumborum beef with different ultimate pH and postmortem aging

The objective of this exploratory study was to assess the changes on lipidome and metabolome profiling of Longissimus lumborum bull muscle with different ultimate pH (pHu) and aging periods. The bull muscles classified as normal, intermediate, or high pHu were collected from a Brazilian commercial slaughterhouse, cut into steaks, individually vacuum-packaged, and aged for 3 days (3-d) or 21 days (21-d) at 2 °C. Muscle extracts were analyzed for the profiles of both lipids, by mass spectrometry (via direct flow-injection), and metabolites, by nuclear magnetic resonance, with downstream multivariate data analysis. As major results, pairwise comparisons identified C12:0 and C14:0 acylcarnitines as potential biomarkers of the intermediate pHu-muscle, which are related to lipid catabolism for alternative energy metabolism and indicate less protein breakage postmortem. Interestingly, the concentration of arginine at early postmortem aging (3-d) may influence the previously reported improved tenderness in normal and high pHu-muscles. Moreover, upregulation of fumarate, formate, and acetate with increased pHu muscle at 21-d aging indicate more intense tricarboxylic acid cycle, amino acid degradation, and pyruvate oxidation by reactive oxygen species, respectively. These three compounds (fumarate, formate, and acetate) discriminated statistically the muscle with high pHu at 21-d aging. The normal pHu-muscle showed higher concentrations of glycogenolysis and glycolysis metabolites, including glucose, mannose, and pyruvate. Hence, our results enhance knowledge of postmortem biochemical changes of beef within different pHu groups aged up to 21 days, which is essential to understand the mechanisms underpinning bull meat quality changes.

Targeted-metabolomic and untargeted-proteomic approaches reveal the effects of muscle fibre type and postmortem ageing on taste-active compounds in beef

The taste of beef is caused by taste-active compounds detected in the mouth during mastication. We hypothesised that the concentration of taste-active compounds in beef is influenced by muscle-fibre-type and postmortem ageing. To test this, and unravel the underlying mechanisms, we investigated the taste-active compounds, and proteomic profiles, in beef masseter [oxidative muscle, all type I fibres) and cutaneous trunci (glycolytic muscle, mostly type II fibres) before and after 14-days postmortem ageing. Our results showed that nucleotides were initially higher and degraded slower in cutaneous trunci (P < 0.05 for both), which could be explained by the profile of nucleotide metabolism enzymes. In contrast, free amino acids were initially higher and increased more in masseter compared to cutaneous trunci (P < 0.05 for all), which might be explained by the profile and activity of proteases in these two muscles. Our results indicate the taste of beef is affected by the muscle-fibre-type and postmortem ageing.

Ultrasound combined with post-mortem aging enriches antioxidant peptides in Muscovy ducks

To investigate the impact of ultrasound in conjunction with post-mortem aging on antioxidant peptides in Muscovy ducks, this study was conducted under appropriate ultrasound conditions (20 min, 20 kHz, 1050 W), followed by post-mortem aging at 4 °C for 6, 12, 24,72 and 168 h. The analysis focused on the peptide content and antioxidant activity of Muscovy ducks. The results revealed that the peptide content reached the highest of 14.02 mg/g of meat following 72 h post-mortem aging combined with ultrasound treatment; an increase of 1.20 mg/g of meat of peptides was observed compared with the control. Moreover, the antioxidant activity also reached its peak (DPPH· scavenging efficacy was 47.38%). The sarcomeres almost completely disappeared after ultrasound treatment, the M and Z lines darkened, and the activities of cathepsins B, D, H, and L and calpain proteases increased. Gel filtration chromatography and reversed-phase high-performance liquid chromatography were utilized to isolate the peptides with the most potent antioxidant activity. Nine of the sequenced peptides were deemed reliable. ENHHCCC exhibited the highest antioxidant activity. Therefore, ultrasound in conjunction with post-mortem aging is a promising method to enrich antioxidant peptides in Muscovy duck.

Ultrasound-induced modifications of beef flavor characteristics during postmortem aging

To investigate the effect of ultrasound treatment on the flavor profile of beef during postmortem aging, a comprehensive analysis of beef flavor was conducted at 0, 7, and 12 d of aging using sensory evaluation and electronic nose. Furthermore, the key volatile flavor compounds were identified using gas chromatography-mass spectrometry (GC–MS), and the odor activity value (OAV) was further evaluated. In addition, the primary pathway involved in flavor formation during beef aging after ultrasound treatment was explored. The results indicated that ultrasound enhanced the flavor profile of beef during postmortem aging by modifying the OAV of hexanal, heptanal, octanal, nonanal, decanal, (Z)-2-nonenal, dodecanal, pentanal, 1-octen-3-ol, octanoic acid, and 2-pentylfuran. Lipid oxidation was a crucial pathway through which ultrasound promoted the generation of volatile flavor compounds in beef, confirmed by the improved oxidation level of fatty acids, particularly monounsaturated ones. The study indicates that ultrasound technology can be regarded as an effective method for enhancing the beef flavor profile during postmortem aging.

Endoplasmic reticulum stress improved chicken tenderness, promoted apoptosis and autophagy during postmortem ageing

In this study, endoplasmic reticulum (ER) stress inducer tunicamycin (TM) and inhibitor 4-phenylbutyric acid (4-PBA) were used to treat postmortem chicken breast muscle to investigate changes in tenderness and effects on apoptosis and autophagy during 5 days ageing. TM-induced ER stress reduced shear force, enhanced myofibril fragmentation index (MFI), disrupted myofibril structure, increased desmin degradation, and activated μ-calpain and caspase-12. In addition, TM-induced ER stress increased the expression of Bax, Bim, and cytochrome c, and decreased the expression of Bcl-xL. Furthermore, TM-induced ER stress improved the conversion of LC3I to LC3II, raised the expression of Beclin-1, and decreased the expression of p62, PI3K, and mTOR. The opposite results were observed after 4-PBA treatment. These results suggested that ER stress could improve chicken tenderness, promote apoptosis and autophagy during chicken postmortem ageing.

Effects of oxidative stress and protein S-nitrosylation interactions on mitochondrial pathway apoptosis and tenderness of yak meat during postmortem aging

To reveal the interaction of oxidative stress and protein S-nitrosylation on mitochondrial pathway apoptosis and tenderness development in postmortem yak meat. Herein, we selected yak longissimus dorsi muscle as the research object and treated hydrogen peroxide (H2O2) with S-nitrosoglutathione agent (GSNO) as well as Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) in mixed injections with 0.9 % saline as a control group, followed by incubation at 4 °C for 12, 24, 72, 120 and 168 h. Results showed that this interaction significantly increased mitochondrial ROS and NO content (P < 0.05) while weakening the antioxidant capacity of GSH and TRX redox response systems or accelerating the Ca2+ release process, leading to mitochondrial functional impairment and increased apoptosis rate. Notably, the H2O2 + L-NAME group showed more pronounced apoptosis. Hence, we suggest that the interaction between oxidative stress and protein S-nitrosylation could positively regulate yak meat tenderization.

Monitoring the Aging and Edible Safety of Pork in Postmortem Storage Based on HSI and Wavelet Transform.

The process of meat postmortem aging is a complex one, in which improved tenderness and aroma coincide with negative effects such as water loss and microbial growth. Determining the optimal postmortem storage time for meat is crucial but also challenging. A new visual monitoring technique based on hyperspectral imaging (HSI) has been proposed to monitor pork aging progress. M. longissimus thoracis from 15 pigs were stored at 4 °C for 12 days while quality indexes and HSI spectra were measured daily. Based on changes in physical and chemical indicators, 100 out of the 180 pieces of meat were selected and classified into rigor mortis, aged, and spoilt meat. Discrete wavelet transform (DWT) technology was used to improve the accuracy of classification. DWT separated approximate and detailed signals from the spectrum, resulting in a significant increase in classification speed and precision. The support vector machine (SVM) model with 70 band spectra achieved remarkable classification accuracy of 97.06%. The study findings revealed that the aging and microbial spoilage process started at the edges of the meat, with varying rates from one pig to another. Using HSI and visualization techniques, it was possible to evaluate and portray the postmortem aging progress and edible safety of pork during storage. This technology has the potential to aid the meat industry in making informed decisions on the optimal storage and cooking times that would preserve the quality of the meat and ensure its safety for consumption.

Effect of ultrasound-assisted L-lysine treatment on pork meat quality and myofibrillar protein properties during postmortem aging.

This paper aimed to investigate the effects of ultrasound-assisted L-lysine treatment on meat quality and myofibrillar proteins (MPs) properties of pork longissimus dorsi during postmortem aging. The results revealed that the L-lysine (Lys) and/or ultrasound treatment significantly increased (p < 0.05) the water-holding capacity and tenderness of the pork during postmortem aging, while the ultrasound-assisted Lys treatment had the lowest cooking loss, pressurization loss, Warner-Bratzler shear force, and hardness. In addition, L-lysine and/or ultrasound treatment increased (p < 0.05) pH value, T21, and myofibrillar fragmentation index, while the ultrasound-assisted Lys treatment had the highest value. Meanwhile, the protein solubility was increased with Lys and/or ultrasound treatment during postmortem aging, and ultrasound-assisted Lys treatment had the highest solubility, reaching 88.19%, 92.98%, and 91.73% at 0, 1, and 3 days, respectively. The result of protein conformational characteristics showed that Lys and/or ultrasound treatment caused the unfolding of the α-helix structure, resulting in the exposure of more hydrophobic amino acids and buried sulfhydryl groups, ultimately enhancing MPs solubility. In summary, ultrasound-assisted Lys treatment altered the structure of MPs, resulting in the enhancement of the water-holding capacity and tenderness of the pork. PRACTICAL APPLICATION: This study showed that ultrasound-assisted L-lysine (Lys) treatment could enhance the water-holding capacity and tenderness of pork during postmortem aging. The results might provide a reference for the application of ultrasound-assisted Lys treatment on the improvement of pork meat quality. To facilitate practical applications in production, the development of medium and large-sized ultrasound equipment for conducting small-scale and pilot experiments is crucial for future research.

Mitochondrial and endoplasmic reticulum stress pathways regulate tenderness of post-mortem chicken muscle

Apoptosis is closely associated with meat tenderization and calcium chloride (CaCl2) and tea polyphenols (TP) have been shown to have a positive effect on meat tenderness. To examine the mechanism by which apoptosis regulates meat tenderness, chicken breasts were treated with 50 mM CaCl2 and 5 mg/mL TP during 5 days of post-mortem ageing where corresponding tender indexes were measured. The results demonstrated that the shear force was highly reduced by 30.74% and 53.64% in chicken breasts treated with CaCl2 and TP, respectively, which promoted postmortem degradation of troponin-T and desmin as well as destruction of myofibrils. Western blot analysis demonstrated that CaCl2 and TP treatments resulted in the activation of calpain-1, caspase-12, -9 and -3, cleavage of PARP, increased the Bax/Bcl-2 ratio, and reduced Bcl-xL levels. In addition, BiP, p-IRE1, and XBP1 factors associated with the endoplasmic reticulum (ER) pathway, were activated during apoptosis. This suggests that the mitochondrial and ER pathways were involved in the induction of apoptosis by CaCl2 and TP during post-mortem ageing. Moreover, ultrastructural damage occurring in mitochondria and nuclei was observed in the morphological features of apoptosis. Consequently, these results suggest that CaCl2 and TP promote meat rejuvenation during ageing process by activating apoptosis via mitochondrial and ER pathways.

Liquid Chromatography-Mass Spectrometry-Based Metabolomics Reveals Dynamic Metabolite Changes during Early Postmortem Aging of Donkey Meat.

Metabolic changes in donkey meat during the early postmortem period have not been previously reported. The LC-MS-based metabolomics technique was conducted to understand the metabolic profiles and identify the key metabolites of donkey meat in the first 48 h postmortem. The pH values showed a decreasing trend followed by an increasing trend. Shear force was the lowest at 4 h and the highest at 24 h (p < 0.05). For the metabolome, some candidate biomarker metabolites were identified, such as adenine, inosine, n-acetylhistidine, citric acid, isocitrate, and malic acid. Predominant metabolic pathways, such as citrate cycle (TCA cycle), alanine, aspartate and glutamate metabolism, and purine metabolism, were affected by aging time. Overabundant n-acetylhistidine was identified in LT, declined at 12 h postmortem aging, and then increased. This may explain the significantly lower pH at 12 h postmortem. Adenine was higher at 4 h postmortem, then declined. Decreased ADP may indicate a fast consumption of ATP and subsequent purine metabolism in donkey meat. The results of this study provided new insights into early postmortem aging of donkey meat quality.

Depth of Interbreed Difference in Postmortem Bovine Muscle Determined by CE-FT/MS and LC-FT/MS Metabolomics.

Japanese Brown (JBR) cattle have moderately marbled beef compared to the highly marbled beef of Japanese Black (JBL) cattle; however, their skeletal muscle properties remain poorly characterized. To unveil interbreed metabolic differences over the previous results, we explored the metabolome network changes before and after postmortem 7-day aging in the trapezius muscle of the two cattle breeds by employing a deep and high-coverage metabolomics approach. Using both capillary electrophoresis (CE) and ultra-high-performance liquid chromatography (UHPLC)-Fourier transform mass spectrometry (FT/MS), we detected 522 and 384 annotated peaks, respectively, across all muscle samples. The CE-based results showed that the cattle were clearly separated by breed and postmortem age in multivariate analyses. The metabolism related to glutathione, glycolysis, vitamin K, taurine, and arachidonic acid was enriched with differentially abundant metabolites in aged muscles, in addition to amino acid (AA) metabolisms. The LC-based results showed that the levels of bile-acid-related metabolites, such as tauroursodeoxycholic acid (TUDCA), were high in fresh JBR muscle and that acylcarnitines were enriched in aged JBR muscle, compared to JBL muscle. Postmortem aging resulted in an increase in fatty acids and a decrease in acylcarnitine in the muscles of both cattle breeds. In addition, metabolite set enrichment analysis revealed that JBR muscle was distinctive in metabolisms related to pyruvate, glycerolipid, cardiolipin, and mitochondrial energy production, whereas the metabolisms related to phosphatidylethanolamine, nucleotide triphosphate, and AAs were characteristic of JBL. This suggests that the interbreed differences in postmortem trapezius muscle are associated with carnitine/acylcarnitine transport, β-oxidation, tricarboxylic acid cycle, and mitochondrial membrane stability, in addition to energy substrate and AA metabolisms. These interbreed differences may characterize beef quality traits such as the flavor intensity and oxidative stability.

Effect of mitochondrial calcium homeostasis-mediated endogenous enzyme activation on tenderness of beef muscle based on MCU modulators

The mitochondrial calcium uniporter (MCU) occupies a noteworthy position in the regulation of mitochondrial calcium uptake. This study investigated the effects of MCU modulator-mediated mitochondrial calcium on mitochondrial dysfunction, oxidative stress, endogenous enzyme activities, and tenderness during postmortem aging. Spermine, as an activator of MCU, resulted in an increase in mitochondrial calcium levels, not only disrupting mitochondrial morphology but also triggering mitochondrial oxidative stress and downregulation of antioxidant factors. Additionally, the spermine group underwent later activation of calpain and earlier activation of caspases, as well as the myofibril fragmentation index was initially lower and then higher compared with control group, indicating that endogenous enzymes played an indispensable role in different aging periods. Interestingly, the results of the Ru360 (an inhibitor of MCU) group were opposite to those aforementioned findings. Our data provide a novel perspective on the regulatory mechanism of mitochondrial calcium homeostasis mediated by MCU on tenderness.

Potential Effects of NO-Induced Hypoxia-Inducible Factor-1α on Yak Meat Tenderness during Post-Mortem Aging.

The objective of this study was to investigate the mechanism underlying nitric oxide (NO)-induced hypoxia-inducible factor-1α (HIF-1α) and its impact on yak muscle tenderness during post-mortem aging. The Longissimus thoracis et lumborum (LTL) muscle of yak were incubated at 4 °C for 0, 3, 6, 9, 12, 24, and 72 h after treatment with 0.9% saline, NO activator, or a combination of the NO activator and an HIF-1α inhibitor. Results indicated that elevated NO levels could increase HIF-1α transcription to achieve stable expression of HIF-1α protein (P < 0.05). Additionally, elevated NO triggered HIF-1α S-nitrosylation, which further upregulated the activity of key glycolytic enzymes, increased glycogen consumption, accelerated lactic acid accumulation, and decreased pH (P < 0.05). These processes eventually improved the tenderness of yak muscle during post-mortem aging (P < 0.05). The results demonstrated that NO-induced activation of HIF-1α S-nitrosylation enhanced glycolysis during post-mortem aging and provided a possible pathway for improving meat tenderness.

Evaluation of Fresh and Frozen Beef Strip Loins of Equal Aging Periods for Palatability Traits

Although studies evaluating freezing are prevalent, most have used varied postmortem aging times to facilitate study design. The lack of a comprehensive study evaluating equally aged fresh and frozen steaks prevents a true under-standing of the impact of freezing. Therefore, the objective of this study was to determine the eating quality and consumer perception differences between fresh and frozen beef steaks of 3 equal aging periods. Beef carcasses were selected from a processing plant on 2 kill dates 1 wk apart to allow for a 1-wk freezing period, fabricated, and aged for 21, 28, or 35 d. On the same day, all samples of equal aging periods were fed to consumer and trained sensory panelists, sheared for shear force, and powdered for lab assays. For consumer panels, the first 4 steaks were given with no additional information, whereas the last 4 steaks were served with the labels “previously frozen” or “fresh, never frozen.” The consumer panelists rated the frozen samples as more tender (P&amp;lt;0.05) than the fresh samples but found no other differences (P&amp;gt;0.05). Even when given additional information, the perception of quality was not impacted (P&amp;gt;0.05). Similarly, the trained panelists rated the frozen samples higher (P&amp;lt;0.05) than the fresh counterparts for overall tenderness, but the fresh samples scored higher (P&amp;lt;0.05) for initial and sustained juiciness. Supporting the sensory data, the frozen steaks had lower (P&amp;lt;0.05) shear force values regardless of the aging period. However, the fresh samples resulted in lower (P&amp;lt;0.05) purge and cook loss. Although some meat quality factors were impacted by freezing, the overall eating quality and perception of quality were not negatively impacted. Therefore, frozen meat should not be discounted due to the eating quality or perception of the quality of beef steaks.