Lipid stability and meat colour of beef from pasture- and grain-fed cattle with or without vitamin E supplement

The Oxidative and Color Stability of Beef from Steers Fed Pasture or Concentrate during Retail Display

Beef production in Uruguay is based on pasture (~85%) or concentrate (~15%), resulting in differences in meat quality. The objective of this study was to compare the oxidative stability and color of beef from these two systems during refrigerated retail display. For these purposes, the Semimembranosus muscle was removed from ten Aberdeen Angus steers raised and fed on pasture (130 days prior to slaughter) and from another ten steers fed concentrate (100 days prior to slaughter), sliced. The muscles were placed in a refrigerated showcase for 3, 6, and 9 days. The contents of β-carotene, α-tocopherol, and fatty acids were determined before the meat was placed on display. Lipid and protein oxidation, color, and heme iron content were determined before and during display. The meat from pasture-fed steers had a lower intramuscular fat content (1.78 ± 0.15 vs. 4.52 ± 0.46), lower levels of monounsaturated fatty acids, a lower n-6/n-3 ratio, less lipid and protein oxidation, lower L* and a* values, and higher levels of α-linolenic acid, DHA, total n-3, β-carotene, and α-tocopherol. In conclusion, the meat from pasture-fed steers was more stable during retail display from an oxidative point of view, which may be due to its higher levels of antioxidant compounds such as β-carotene and α-tocopherol and had a healthier fatty acid profile for consumers.

Ergothioneine: new functional factor in fermented foods

Ergothioneine (EGT) is a high-value natural sulfur-containing amino acid and has been shown to possess extremely potent antioxidant and cytoprotective activities. At present, EGT has been widely used in food, functional food, cosmetics, medicine, and other industries, but its low yield is still an urgent problem to overcome. This review briefly introduced the biological activities and functions of EGT, and expounded its specific applications in food, functional food, cosmetic, and medical industries, introduced and compared the main production methods of EGT and respective biosynthetic pathways in different microorganisms. Furthermore, the use of genetic and metabolic engineering methods to improve EGT production was discussed. In addition, the incorporation of some food-derived EGT-producing strains into fermentation process will allow the EGT to act as a new functional factor in the fermented foods.

Evaluating the Shelf Life and Sensory Properties of Beef Steaks from Cattle Raised on Different Grass Feeding Systems in the Western United States

Consumer interest in grass-fed beef has been steadily rising due to consumer perception of its potential benefits. This interest has led to a growing demand for niche market beef, particularly in the western United States. Therefore, the objective of this study was to assess the impact of feeding systems on the change in microbial counts, color, and lipid oxidation of steaks during retail display, and on their sensory attributes. The systems included: conventional grain-fed (CON), 20 months-grass-fed (20GF), 25-months-grass-fed (25GF) and 20-months-grass-fed + 45-day-grain-fed (45GR). The results indicate that steaks in the 20GF group displayed a darker lean and fat color, and a lower oxidation state than those in the 25GF group. However, the feeding system did not have an impact on pH or objective tenderness of beef steaks. In addition, consumers and trained panelist did not detect a difference in taste or flavor between the 20GF or 25GF steaks but expressed a preference for the CON and 45GR steaks, indicating that an increased grazing period may improve the color and oxidative stability of beef, while a short supplementation with grain may improve eating quality.

Effect of Feeding Alfalfa and Concentrate on Meat Quality and Bioactive Compounds in Korean Native Black Goat Loin during Storage at 4°C

The primary aim of this study was to evaluate the effect of feeding alfalfa: Concentrate at different ratios (8:2 or 2:8) to Korean native black goats (KNBG) for 90 days on meat quality and bioactive compound content. Feeding KNBG alfalfa and concentrate at different ratios did not impact meat pH, color, microorganism composition, volatile basic nitrogen levels, or lipid oxidation. The low alfalfa (KLA) group exhibited increased oleic acid and monosaturated fatty acid levels, both of which impact the palatability traits of meat. The abundance of bioactive compounds increased in the loin meat of the KLA group, leading to an increase in antioxidant activities. Our results suggest that feeding alfalfa and concentrate at a 2:8 ratio to KNBG can increase taste-related fatty acids and bioactive compounds in loin meat, relative to that achieved by feeding at an 8:2 ratio. Further investigation is required to evaluate the quality and the metabolites of bioactive compounds in KNBG meat and the effect of the different dietary ratios of forage and concentrate.

RNA-Seq Analysis Reveals the Potential Molecular Mechanisms of Puerarin on Intramuscular Fat Deposition in Heat-Stressed Beef Cattle

To investigate the effect of Puerarin on intramuscular fat deposition in heat-stressed beef cattle and its underlying mechanism. Thirty-two healthy Jinjiang bulls were randomly divided into four groups and dietary with 0 (Control), 200 (Pue200), 400 (Pue400), and 800 (Pue800) mg/kg Puerarin in the feed concentrate. The results showed that Puerarin treatment enhanced the concentration of crude fat, fatty acid (C14:1 and C17:1), and the activity of fatty acid synthase in Longissimus thoracis (LT), but decreased the levels of blood leptin (P < 0.05). High-throughput sequencing of mRNA technology (RNA-Seq) was used and the analysis showed that 492 genes were down-regulated and 341 genes were up-regulated in LT, and these genes were significantly enriched to the pathways related to lipid metabolism. These results indicated that dietary supplemental with Puerarin enhanced intramuscular fat deposition by regulating lipid metabolism of heat-stressed beef cattle.

Tropical Beef: Is There an Axiomatic Basis to Define the Concept?

Cattle production in tropical regions has been estimated to account for just over half of cattle worldwide, yet it has not been demonstrated that sufficient similarities in the cattle exist to describe tropical cattle and, even less so, to characterize the meat from these animals. The aim of this review is to investigate the quality and nutrient composition of meat from cattle raised in the Tropics to determine if there is an axiomatic basis that would allow the definition of a concept of “tropical beef”. Tropical beef is the meat obtained from cattle raised in tropical environments, the population of which remains largely uncharacterized. Production systems in the Tropics are highly diverse but converge on the use of indigenous and Bos indicus breeds or Bos indicus-influenced crossbreeds under pasture feeding regimes. While some systems allow cattle to be slaughtered at ≤2 years of age, most often animals are ≥3 years. These production systems generally produce lean, low-yielding carcasses and tough (>46 N), lean (≤3.6% intramuscular fat) meat with a macronutrient composition otherwise similar to beef from animals raised elsewhere (72–74% moisture and 20–24% protein). Fatty acid profiles depend on the breed and production systems, while mineral content is influenced by the environment. Although lean and tough, tropical beef is highly acceptable to the consumers it serves, is culturally and traditionally relevant and, in many countries, contributes to food security. Consolidating the findings from animal and meat science studies in the Tropics has allowed the demonstration of an axiomatic basis defining “tropical beef” as a concept.

Effects backgrounding-finishing programs of different age/weight at harvest of feedlot steers

Four ages at harvest (HA: A15, A18, A24 and A30 for 15, 18, 24 and 30 months, respectively) were compared in performance, carcass and meat traits of feedlot finished steers over a 123-day period. Three meat aging periods (postmortem days: 2, 7 and 14) were imposed on a longissimus thoracis muscle (LM) section of each left carcass. Feed efficiency (FE) was greater (P ≤ 0.02) for A15 and A18. Treatment A30 had the lowest FE (P ≤ 0.02). The LM area was largest for A30, but no different (P = 0.15) from A24. Intramuscular fat was lowest (P < 0.01) for A15. No differences were detected (P ≥ 0.11) among the A18, A24 and A30. Treatment A30 had the highest rib fat thickness (P ≤ 0.02) and WBsf values. No differences were detected (P ≥ 0.25) in WBSf between A15, A18 and A24 after any aging period. Results suggested A24 as a threshold for carcass and meat traits.

The Effect of Grazing Level and Ageing Time on the Physicochemical and Sensory Characteristics of Beef Meat in Organic and Conventional Production

This study investigated the influence of the production system (conventional vs. organic), the grass consumption level and the ageing period (7 and 14 days) on beef quality. Three groups of samples from Limousin × Avileña calves were analysed: F100, formed by animals fed 100% on forage; F74, formed by animals fed on an average amount of forage of 74%; and F35, formed by animals fed on straw fodder (35%) and concentrate (65%). The results showed that the higher the grass content, the lower the fat oxidation and the higher the n-3 content, but also the higher the SFA level, the initial Warner-Bratzler shear force (WBSF), and the more residue it leaves on chewing. As for the effect of production system, organic samples showed higher intramuscular fat content and lower moisture and MUFA content. These samples were darker and showed lower values for flavour quality. Among the organic samples, F100 had higher n-3 and CLA content and higher values for colour, hardness, odour and flavour quality. Increased ageing time may improve the sensory characteristics of the meat, especially in the case of the F100 samples. The results pointed out that F100 samples aged at least 14 days showed the best physico-chemical, nutritional and sensory characteristics.

Effects of dietary ferulic acid on growth performance, carcass traits and meat quality of heifers

BACKGROUND

Ferulic acid is a natural occurring compound with antioxidant and antimicrobial bioactive properties, and recently was proposed as a new alternative growth promoter in meat-producing animals without changing meat quality parameters. The present study aimed to evaluate the impact of two doses of ferulic acid (FA) on the feedlot performance, carcass traits, and physicochemical and sensory characteristics of meat quality in commercial heifers. Ninety heifers (3/4 Bos taurus; n = 270; body weight = 480 ± 10 kg) were randomly assigned to one of the following treatments (30 days): Control, fed with a basal diet; FA250 or FA500 offered the same diet further supplemented with FA at 250 or 500 mg kg^-1 feed, respectively. Feedlot performance, carcass traits, and physicochemical and meat sensory characteristics were evaluated.

RESULTS

FA supplementation increased average daily gain (ADG) by 21%, hot carcass weight by 1.8% and cold carcass weight by 1.6% with respect to the control (P < 0.05). FA500 treatment caused a decrease (P < 0.05) in some carcass traits. However, carcass characteristics of economic importance, such as cold carcass dressing and LT muscle area, were improved by FA250 supplementation (P < 0.05), causing a possible growth promoter effect. Physicochemical and sensory parameters of meat were not altered by FA supplementation (P > 0.05).

CONCLUSION

Ferulic acid has the potential for use as a growth promoter additive in finishing heifers without negatively affecting the meat quality, as occurs with some synthetic growth promotants compounds used in animal production. © 2020 Society of Chemical Industry.

Insights on meat quality from combining traditional studies and proteomics

Following a century of major discoveries on the mechanisms determining meat colour and tenderness using traditional scientific methods, further research into complex and interactive factors contributing to variations in meat quality is increasingly being based on data-driven "omics" approaches such as proteomics. Using two recent meta-analyses of proteomics studies on beef colour and tenderness, this review examines how knowledge of the mechanisms and factors underlying variations in these meat qualities can be both confirmed and extended by data-driven approaches. While proteomics seems to overlook some sources of variations in beef toughness, it highlights the role of post-mortem energy metabolism in setting the conditions for development of meat colour and tenderness, and also points to the complex interplay of energy metabolism, calcium regulation and mitochondrial metabolism. In using proteomics as a future tool for explaining variations in meat quality, the need for confirmation by further hypothesis-driven experimental studies of post-hoc explanations of why certain proteins are biomarkers of beef quality in data-driven studies is emphasised.

Flavor Characterization of Grass- and Grain-Fed Australian Beef Longissimus Thoracis Aged 35 to 65 Days Postmortem

Our objective was to investigate the effects of extended aging on the flavor characteristics of Australian grass- and grain-fed beef longissimus thoracis. Ribeye rolls from Australian grass- and grain-fed beef carcasses were collected, randomly assigned to one of 4 postmortem aging days (35, 45, 55, and 65), vacuum packaged, and shipped under refrigeration (0°C–2°C) to Texas Tech University (Lubbock, TX). Aged longissimus thoracis were fabricated on their respective aging day into 2.54-cm steaks, vacuum packaged individually, and frozen (−24°C) until further analyses. According to trained flavor panelists, beef flavor identity, fat-like, metallic, umami, bitter, and sweet flavors were not influenced by diet or postmortem aging (P &gt; 0.05). Diet influenced (P &lt; 0.05) liver-like, rancid, grassy, and sour flavors, as well as juiciness. For all flavors except liver-like, grass-fed samples had stronger flavors than grain-fed samples. Postmortem aging influenced (P &lt; 0.05) bloody/serumy, liver-like, rancid, and grassy flavors, along with tenderness and juiciness. Flavor detection typically became stronger for those flavors as postmortem aging increased; however, bloody/serumy, juiciness, and tenderness generally did not follow a linear trend as postmortem aging increased. Content of acetic acid and hexanal were each greater (P &lt; 0.05) in grain-fed beef. The majority of lipid oxidation compounds were most prominent (P &lt; 0.05) in samples aged 45 and 55 d, while content in 35 and 65 d were lower and did not differ (P &gt; 0.05). Aging also influenced content of acetic acid and ethanol (P ≤ 0.04), which increased with aging duration. For 1-octen-3-ol, grain-fed samples aged 65 d had the greatest (P &lt; 0.05) content compared with all other diet and aging combinations. Results indicate that aging up to 65 d had no impact on beef flavor identity and umami, but it led to stronger generation of certain off-flavors such as rancid, grassy, and liver-like.

Effects of supplementing docosahexaenoic acid-rich microalgae and antioxidants on beef longissimus lumborum steak color stability and sensory characteristics. Transl Anim Sci 2020;4:txaa135. [PMID: 32775965 PMCID: PMC7399536 DOI: 10.1093/tas/txaa135]

The objective of this study was to determine the effects of four microalgae and antioxidant feeding regimens on beef longissimus lumborum color stability and palatability. Steers were blocked by weight and randomly assigned to one of four dietary treatments fed during a 45-d feeding period. Treatments (n = 10 per treatment) consisted of a control diet (CON) and control diet plus 100 g∙steer⁻¹∙d⁻¹ microalgae (ALGAE), ALGAE plus antioxidants (103 IU/d vitamin E and Sel-Plex) fed throughout feeding (AOX), and AOX fed for the final 10 d of finishing (LATE). The longissimus lumborum muscle was removed, aged for 14 d, and fabricated into steaks for objective and subjective color and palatability analyses. There were treatment × day of display interactions for a* value and steak surface metmyoglobin percentage (P < 0.01). There were no treatment differences through day 4 of display for a* value (P > 0.16) and day 5 of display for surface metmyoglobin (P > 0.10). By day 10 of display, ALGAE steaks had a smaller a* value than all other treatments (P < 0.01). Steaks from AOX steers had a greater (P < 0.01) a* value than CON steaks, whereas both a* values did not differ from LATE steaks (P > 0.19). By the end of display, ALGAE steaks had more metmyoglobin than the other treatments (P < 0.01). Steaks from AOX steers had less metmyoglobin than CON and LATE steaks (P < 0.04), which did not differ (P > 0.25). Treatment did not affect trained panel ratings (P > 0.15); however, treatment did affect (P < 0.01) off-flavor intensity. Steaks from ALGAE and AOX steers had greater off-flavor ratings than CON steaks (P < 0.03), but did not differ (P = 0.10). Steaks from LATE steers did not differ in off-flavor ratings from the other treatments (P > 0.07). Use of antioxidants improved color stability of steaks from microalgae fed steers; however, panelists still detected off-flavors.

Seasonal differences exist in the polyunsaturated fatty acid, mineral and antioxidant content of U.S. grass-finished beef

There is increased consumer interest in grass-finished beef (GFB) with retail sales reaching $272 million in 2016. GFB contains higher omega-3 fatty acid levels compared to grain-finished beef, but variations in fatty acid (FA), mineral, and antioxidant content by producers and season is poorly documented. Hence, GFB samples from cattle finished in both fall and spring were obtained from four producers representing several US sub-regions. FAs were extracted using microwave-assisted extraction, derivatized to methyl-esters, and quantified using gas chromatography-mass spectrometry. Mineral content was quantified using coupled plasma mass-spectrometry and antioxidants were quantified via UV-absorption. Overall, total omega-3 FA content was greater in beef from cattle finished in the spring (13.4 mg/100g beef) than the fall (10.3; P<0.001). Additionally, α-tocopherol was present in greater amounts in spring-finished beef (259 vs. 223 ug/100g beef, P<0.001) as was the micromineral selenium (18.2 vs. 17.3ug/100g beef, P = 0.008). Despite using the same feed in fall and spring, cattle from producer 4 had higher total omega-3, omega-6, and total polyunsaturated fatty acids in spring compared to fall (P<0.010). These results suggest there are seasonal differences in omega-3 and omega-6 fatty acids, minerals and antioxidants in grass-finished beef independent of finishing diet.

Stability of fatty acid composition of intramuscular fat from pasture- and grain-fed young bulls during the first 7 d postmortem

In order to study the effect of different amounts of concentrate feed and the effectiveness of natural antioxidants on the fatty acid stability of intramuscular fat during the first days postmortem, 75 young bulls of the Retinta breed were divided in three groups: 30 were grazed, 30 were fed on medium concentrate diets, and 15 were fed on high-concentrate diets. Young bulls were slaughtered at commercial weight, around a 500 kg final body weight. Samples from Longissimus lumborum muscle were assigned to two ageing periods (0 and 7 d) and were vacuum packaged in vacuum bags (O2 permeability: 9.3 mL O2/m2 per 24 h at 0 ∘C) using an EGARVAC® sealer. Beef from grass-fed bulls showed a higher polyunsaturated fatty acid content than concentrate-fed bulls. During the first 7 d postmortem, no changes in the fatty acids profile were observed, because α-tocopherol content was optimal to prevent lipid oxidation. The higher level of natural antioxidants in grass than in grain resulted in the stability of the fatty acid profile. This study shows that the anti-oxidative potential of natural antioxidants in meat plays an important role during the first 7 d postmortem.

Grass finishing and the residual effect of pasture prior to concentrate finishingon the shelf stability of late-maturing bull beef

Context The finishing of late-maturing bulls on grass is economically more favourable than finishing on cereal concentrates but it may have a negative effect on oxidative stability. Aim To determine the effect of varying levels of pasture feeding during the finishing period on the oxidative stability of bull beef. Methods Groups of eight late-maturing breed sired bulls were assigned to one of the following production systems: (1) pasture only for 200 days (P), (2) pasture only for 100 days followed by pasture plus 50% of the dietary dry matter (DM) intake as concentrate for 100 days (P-C50), (3) pasture plus 50% of the DM intake as concentrate for 200 days (C50), (4) pasture only for 100 days followed by ad libitum concentrates for 100 days (P-C), (5) pasture plus 50% of the DM intake as concentrate for 100 days followed by ad libitum concentrates for 100 days (C50-C) and (6) ad libitum concentrates offered indoors for 200 days (C). The M. Longissimus thoracis et lumborum muscle was excised post-slaughter for proximate, fatty acid and α-tocopherol analysis and for measurement of lipid and protein oxidation and colour stability. Results The polyunsaturated fatty acid (PUFA) concentration and proportion in muscle were higher (P &lt; 0.001) in C50 bulls compared with P, P-C50 and P-C bulls. The concentration of highly peroxidisable PUFA was at least 1.3-fold higher (P &lt; 0.001) in the muscle of C50 bulls than of C and P-C bulls whereas the proportion was at least 1.5-fold higher (P &lt; 0.001) in muscle of P, P-C50 and C50 bulls compared with C and P-C bulls. There was a higher (P &lt; 0.001) concentration of saturated fatty acids and monounsaturated fatty acids in muscle of bulls fed on concentrate in the last 100 days (P-C, C50-C and C) compared with those fed on grass (fully or partially) in the last 100 days (P, P-C50 and C50). α-Tocopherol concentration was at least 1.5-fold higher (P &lt; 0.001) in muscle of P bulls compared with C, C50-C and P-C bulls. Redness, redness stability, lipid and protein oxidation did not differ between treatments (P &gt; 0.05). Conclusions The increase in highly peroxidisable PUFA in beef, by increasing pasture in the finishing ration did not increase susceptibility to oxidation, most likely due to a concomitant increase in α-tocopherol. Implications Beef can be produced from late-maturing bulls grazing on pasture for 200 days without impacting negatively on oxidative stability.

Preliminary investigation into the use of Raman spectroscopy for the verification of Australian grass and grain fed beef

Australian grass and grain-fed beef products attract premium prices at sale and several beef processors market beef underwritten by production system claims. This preliminary investigation assessed the feasibility of using Raman spectroscopy to detect differences in the chemical composition of subcutaneous fat from cattle raised in extensive and intensive production systems. Raman spectra, fatty acid composition, β-carotene composition and objective colour measurements were measured on 150 grass and 150 grain-fed cattle. Spectral differences at peaks including 1069 cm^-1, 1127 cm^-1, 1301 cm^-1 and 1445 cm^-1 suggest that Raman spectra is able to detect differences in saturated fatty acids, which were significantly higher in carcases from grain-fed cattle. Differences in spectra at 1658 cm^-1 were observed, however further research is required to investigate the cause of this spectral feature. Overall, this study indicated that Raman spectroscopy is a potential tool for the authentication of beef carcases from grass and grain-fed production systems.

The effects of graded levels of concentrate supplementation on colour and lipid stability of beef from pasture finished late-maturing bulls

Finishing late-maturing bulls on grass may alter the antioxidant/prooxidant balance leading to beef with higher susceptibility to lipid oxidation and a lower colour stability compared to bulls finished on cereal concentrates. In this context, lipid oxidation and colour stability of beef from late-maturing bulls finished on pasture, with or without concentrate supplements, or indoors on concentrate was assessed. Charolais or Limousin sired bulls (n = 48) were assigned to four production systems: (1) pasture only (P), (2) pasture plus 25% dietary DM intake as barley-based concentrate (PC25), (3) pasture plus 50% dietary DM intake as barley-based concentrate (PC50) or (4) a barley-based concentrate ration (C). Following slaughter and postmortem ageing, M. Longissimus thoracis et lumborum was subjected to simulated retail display (4°C, 1000 lux for 12 h out of 24 h) for 3, 7, 10 and 14 days in modified atmosphere packs (O2 : CO2; 80 : 20). Lipid oxidation was determined using the 2-thiobarbituric acid-reactive substances assay; α-tocopherol was determined by HPLC; fatty acid methyl esters were determined using Gas Chromatography. Using a randomised complete block design, treatment means were compared by either ANOVA or repeated measures ANOVA using the MIXED procedure of SAS. Total polyunsaturated fatty acid (PUFA) concentrations were not affected by treatment, n-3 PUFAs were higher (P < 0.001) and the ratio of n-6 to n-3 PUFAs was lower (P < 0.001) in muscle from P, PC25 and PC50 compared to C. α-Tocopherol concentration was higher in muscle from P compared to PC50 and C bulls (P = 0.001) and decreased (P < 0.001) in all samples by day 14. Lipid oxidation was higher in muscle from C compared to P bulls on day 10 and day 14 of storage (P < 0.01). Finishing on pasture without supplementation did not affect beef colour stability and led to lower lipid oxidation, possibly due to the higher α-tocopherol concentration compared to concentrate finished beef.

Feeding strategies alter gene expression of the calpain system and meat quality in the longissimus muscle of Braford steers

Objective

The aim of the present study was to determine the effect of supplementing pasture-finished steers with corn silage on the expression level of the calpain system proteins and beef tenderization.

Methods

Thirty Braford steers grazing on summer pasture were used for the study. For 120 days fifteen animals were supplemented with corn silage at 1% of body weight per head per day (Suppl) whereas the remaining 15 steers only received pasture (Contr). Carcass and meat traits were evaluated and compared between groups. Gene expression and activities of proteases (calpain 1 and calpain 2) and inhibitor (calpastatin) were measured using real-time polymerase chain reaction and casein zymography.

Results

Carcass and meat traits were significantly different between feeding systems. Supplemented steers showed higher hot carcass weight (p<0.01), fat content (p = 0.02), and Warner-Bratzler shear force (p = 0.03). Furthermore, the control group showed higher protease:inhibitor ratios, at mRNA (p = 0.01) and protein levels (p<0.10). Warner-Bratzler shear force and mRNA calpains:calpastatin ratio were associated in both feeding systems (p<0.01).

Conclusion

Based on the results obtained in the study, beef tenderness differences among finishing strategies could be modulated through differential expression of the calpain system proteins.

The effect of aging and muscle type on the quality characteristics and lipid oxidation of lamb meat

The research carried out on meat from 45 ram lambs of the Polish merino breed allowed to determine the effect of meat aging and muscle type on physicochemical characteristics and oxidative stability of lipids. Analysis of physicochemical traits (pH, meat color, expressed juice, cooking loss, shear force, moisture, protein, fat and total collagen content) was performed on fresh and meat aged for 14 d in the longissimus lumborum (LL) and gluteus medius (GM) muscles. The meat aging determined all physicochemical characteristics except protein and fat content. More changes in pH and meat color parameters were defined in the GM muscle compared to the LL muscle. The increase in the tenderness of meat expressed as a reduction ( P < 0.05 ) of shear force values was observed in both muscles aged for 14 d. A lower value ( P < 0.05 ) of the shear force, despite the higher content of collagen, was determined in the GM muscle compared to LL. The investigated muscles differed in the degree of lipid peroxidation expressed as thiobarbituric acid-reactive substances (TBARS) in both fresh and aged meat. The TBARS value was lower ( P < 0.05 ) in the LL muscle than in GM. In the longissimus lumborum muscle, the significantly lower content of polyunsaturated fatty acids (PUFAs) and PUFA n-6 has been recorded. The oxidation stability was not influenced by the meat aging.

Timing of Exposure to High-Concentrates versus High-Quality Forages on Growth and Marbling Deposition in Steers

Forty Angus-cross steers (280 ± 21.4 kg BW, 8 mo.) were used to examine the effects of exposure to 2 diets [high concentrate diets (CONC) versus high quality forages (FOR)] during 2 time periods [early (EARLY; at 30-d post weaning) or late (LATE; just prior to slaughter)] on animal growth, marbling deposition and tenderness. Steers were blocked by weight and randomly assigned to four dietary treatments: 1) CONC-FOR, 2) CONC-CONC, 3) FOR-CONC, or 4) FOR-FOR. Exposure to CONC during the EARLY or LATE period increased (P < 0.05) growth and fat deposition compared to FOR-FOR. Hot carcass weight was greater (P < 0.05) for CONC-CONC and FOR-CONC steers than FOR-FOR and CONC-FOR due to changes in dressing percent. Marbling score was greater (P < 0.05) for CONC-CONC and CONC-FOR compared to FOR-FOR. Exposure to CONC during the EARLY period (CONC-FOR and CONC-CONC) increased (P < 0.05) n-6 polyunsaturated fatty acids (PUFA) deposition in longissimus muscle (LM) and subcutaneous adipose tissue (SQ); whereas, exposure to CONC during the LATE period (CONC-CONC and FOR-CONC) reduced (P < 0.05) n-3 PUFA, trans-11 octadecenoic acid and cis-9 trans-11 isomer of conjugated linoleic acid (CLA). Warner-Bratzler shear force at d 2 and 7 of postmortem aging in ribeye steaks from CONC-CONC and FOR-CONC was greater (P < 0.05) than FOR-FOR and CONC-FOR. Lipogenic gene expression was up-regulated (P < 0.05) and lipolytic gene expression was downregulated (P < 0.06) in SQ from CONC-CONC and FOR-CONC compared to FOR-FOR. Overall, exposure to CONC in both periods increased growth rate and marbling deposition but LATE exposure had the greatest impact on adipose lipogenesis and lipolysis, fatty acid composition, and tenderness.

Comparison of ruminal fermentation parameters, fatty acid composition and flavour of beef in finishing bulls fed active dry yeast (Saccharomyces cerevisiae) and yeast culture

This study was conducted to compare the effect of active dry yeasts (ADY) and yeast cultures (YC), two typical products of yeast preparations, on ruminal fermentation parameters, and on the fatty acid composition and flavour of beef from finishing bulls fed a high-concentrate diet. Forty-five finishing bulls (mean bodyweight ± s.d.: 505.4 ± 29.1 kg body weight) were allocated to three groups of 15 bulls and assigned randomly to one of three diets, which were CON diet (basal diet), ADY diet (basal diet + Levucell SC) and YC diet (basal diet + Diamond V XP). After 112 days trial, all bulls (mean bodyweight ± s.d.: 591.6 ± 64.2 kg body weight) were slaughtered. The rumen fluid of each animal was collected at slaughter and cross-sectional samples of longissimus lumborum were collected from three treatments at carcass segmentation after a 24-h chill. The result indicated that both ADY and YC supplementation had no significant effect (P > 0.05) on rumen pH, concentration of ammonia-N and total volatile fatty acid compared with CON. ADY had no significant effect (P > 0.05) on percentage of rumen individual fatty acid whereas YC significantly decreased valerate molar percentage (P = 0.008) and increased acetate molar percentage (P = 0.029) and the ratio of acetate to propionate (P = 0.035). In addition, compared with CON, ADY significantly (P = 0.003) increased the concentration of C16:1n7 and significantly (P = 0.012) decreased the concentration of C18:3n6c compared with CON. YC significantly decreased the concentration of C18:3n6c (P = 0.014) compared with CON. However, both ADY and YC had no significant effect (P > 0.05) on other individual fatty acid concentrations, the proportions of saturated fatty acids and monounsaturated fatty acids and nutritionally important values including the ratio of n-6/n-3, polyunsaturated fatty acids/saturated fatty acid and C18:2n6/C:18:3n3. Both ADY and YC significantly improved beef tenderness for cooking method of chaffy dish (P < 0.05) and beef tenderness also tended improve for ADY (P = 0.075) and YC (P = 0.097) when samples were fried. Both ADY and YC did not show improvements in flavour or juiciness compared with CON for either cooking method.

Carcass traits, meat quality, antioxidant status and antioxidant gene expression in muscle and liver of Hu lambs fed perilla seed

The effects of perilla (Perilla frutescens L.) seed on carcass traits, meat quality, antioxidant status and antioxidant gene expression in the liver and muscle of Hu lambs were investigated in this study. Sixty Hu lambs (23.02 ± 1.36 kg) were randomly divided into four experimental groups receiving diets containing 0%, 5%, 10% or 15% perilla seed (CD, 5%PFSD, 10%PFSD and 15%PFSD, respectively). The addition of perilla seed had no significant impacts on carcass traits (p > .05). There were no differences in pH, meat colour, drip loss, cooking loss or shear force among the four treatments (p > .05). Addition of perilla seed increased (p < .05) deposition of intramuscular lipids but had no effect on other chemical components in the longissimus dorsi (LD) (p > .05). The 15%PFSD diet decreased the total antioxidant capacity (T-AOC) and malondialdehyde (MDA) content in the liver (p < .05 for both) but increased the activity of these antioxidant enzymes in LD (p < .05 for both). Compared to CD, addition of perilla seed increased superoxide dismutase (SOD) and glutathione peroxidase (GPX) expression in the liver and LD (p < .05 for all). These results indicate that perilla seed supplementation in lambs' diets can increase deposition of intramuscular lipids and improve muscular oxidative status and meat quality.

Feeding microalgae meal (All-G Rich; CCAP 4087/2) to beef heifers. I: Effects on longissimus lumborum steak color and palatibility

The objective of this study was to examine effects of 4 levels of microalgae meal (All-G Rich, CCAP 4087/2; Alltech Inc., Nicholasville, KY) supplementation to the diet of finishing heifers on longissimus lumborum (LL) steak PUFA content, beef palatability, and color stability. Crossbred heifers ( = 288; 452 ± 23 kg initial BW) were allocated to pens (36 pens and 8 heifers/pen), stratified by initial pen BW (3,612 ± 177 kg), and randomly assigned within strata to 1 of 4 treatments: 0, 50, 100, and 150 g·heifer·d of microalgae meal. After 89 d of feeding, cattle were harvested and LL were collected for determination of fatty acid composition and Warner-Bratzler shear force (WBSF), trained sensory panel evaluation, and 7-d retail color stability and lipid oxidation analyses. Feeding microalgae meal to heifers increased (quadratic, < 0.01) the content of 22:6-3 and increased (linear, < 0.01) the content of 20:5-3. Feeding increasing levels of microalgae meal did not impact total SFA or MUFA ( > 0.25) but tended ( = 0.10) to increase total PUFA in a quadratic manner ( = 0.03). Total omega-6 PUFA decreased (linear, = 0.01) and total omega-3 PUFA increased (quadratic, < 0.01) as microalgae meal level increased in the diet, which caused a decrease (quadratic, < 0.01) in the omega-6:omega-3 fatty acid ratio. Feeding microalgae meal did not affect WBSF values or sensory panel evaluation of tenderness, juiciness, or beef flavor scores ( > 0.16); however, off-flavor intensity increased with increasing concentration of microalgae meal in the diet (quadratic, < 0.01). From d 5 through 7 of retail display, steaks from heifers fed microalgae meal had a reduced a* value and oxymyoglobin surface percentage, with simultaneous increased surface metmyoglobin formation (quadratic, < 0.01). Lipid oxidation analysis indicated that at d 0 and 7 of display, as the concentration of microalgae meal increased in the diet, the level of oxidation increased (quadratic, < 0.01). Muscle fiber type percentage or size was not influenced by the inclusion of microalgae meal in diets ( > 0.19); therefore, the negative effects of microalgae on color stability were not due to fiber metabolism differences. Feeding microalgae meal to finishing heifers improves PUFA content of beef within the LL, but there are adverse effects on flavor and color stability.

Feeding microalgae meal (All-G Rich; CCAP 4067/2) to beef heifers. II: Effects on ground beef color and palatability

The objective of this study was to examine the effects of feeding microalgae meal (All-G Rich, CCAP 4087/2; Alltech Inc., Nicholasville, KY) to finishing heifers on 85% lean and 15% fat (85/15) ground beef PUFA content, palatability, and color stability. Crossbred heifers ( = 288; 452 ± 23 kg initial BW) were allocated to pens (36 pens and 8 heifers/pen), stratified by initial pen BW (3,612 ± 177 kg), and randomly assigned within strata to 1 of 4 treatments: 0, 50, 100, and 150 g·heifer·d of microalgae meal. After 89 d of feeding, a subset of heifers (3/pen) was harvested and the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius were collected for processing into ground beef. At 42 d postmortem, 85/15 ground beef was formulated and formed into 112-g patties and fatty acid composition, subjective palatability, and 96-h retail color stability analyses were conducted. Increasing dietary microalgae meal concentration increased ground beef 20:5-3 and 22:6-3 fatty acids (quadratic, < 0.01). There was a treatment × hour interaction for all color attributes ( < 0.01). On d 0, microalgae tended ( = 0.08) to decrease L*, but patties had similar L* values the remainder of display ( > 0.12). Feeding microalgae meal affected ( = 0.02) b* at 24 h and decreased (linear, = 0.08) b* at 48 h. From h 0 to 36 of display, microalgae affected redness of patties ( < 0.02), and from 48 to 72 h, microalgae meal decreased a* value (linear, < 0.04). Microalgae meal did not impact sensory panel firmness, overall tenderness, or juiciness scores ( > 0.20) but tended to affect ( = 0.10) cohesiveness scores. As the amount of microalgae meal fed to heifers increased, beef flavor intensity decreased (linear, < 0.01) and off-flavor intensity increased (quadratic, < 0.05). Surface oxymyoglobin and metmyoglobin were impacted by microalgae meal from 12 to 36 h of display ( < 0.01). From 48 to 84 h of display, feeding microalgae meal to heifers decreased (linear, < 0.09) surface oxymyoglobin and increased (linear, < 0.02) surface metmyoglobin of patties. Although feeding microalgae meal to heifers increases the PUFA content of 85/15 ground beef, there are undesirable effects on flavor and color stability.

Effect of including whole linseed and vitamin E in the diet of young bulls slaughtered at two fat covers on the sensory quality of beef packaged in two different packaging systems

BACKGROUND

Forty-six Pirenaica young bulls, slaughtered at two levels of fatness (3 and 4 mm), were used to evaluate the effect of the inclusion of 50 g kg^-1 linseed alone or with 200 IU vitamin E kg^-1 in the concentrate and of the meat packaging system (vacuum or modified atmosphere packaging (MAP)) on the beef sensory quality.

RESULTS

The inclusion of linseed or supplementation with vitamin E in the concentrate induced no significant differences in the main meat sensory scores and overall appraisal except under MAP, where small differences due to concentrate ingredients were found in juiciness and metallic flavor intensity. Extending the display time up to 4 or 8 days in high-oxygen MAP had detrimental effects on sensory attributes. Meat from animals with 4 mm fat cover depth were rated more tender and juicy, less fibrous and with a higher intensity of beef flavor and rancid odor than meat from 3 mm fat cover bulls when both samples were vacuum packaged.

CONCLUSION

The inclusion of 50 g kg^-1 linseed in the concentrate fed to bulls had no detrimental effect on the beef sensory quality. The vacuum-packaged meat of bulls slaughtered at 4 mm fat cover was rated higher on sensory analysis than that at 3 mm fat cover. © 2016 Society of Chemical Industry.

Influence of vacuum-ageing duration of whole beef on retail shelf life of steaks packaged with oregano (Origanum vulgare L.) active film under high O2

Beef Longissimus lumborum (LL) was no aged (LL0), aged for 7 days (LL7) and 14 days (LL14) under vacuum at 1 ± 1 °C. The obtained beefsteaks were packaged in high oxygen (Hi-O2) with active packaging (AP) during 13-21 days at 1 ± 1 °C. Redness (CIE a* values), metmyoglobin percentage (MetMb%), total flora (PCA), thiobarbituric acid-reactive substances (TBA-RS), instrumental tenderness (Warner-Bratzler shear force: WBSF), and sensory analyses were performed. The various variables differed amongst the ageing times and packaging systems (AP vs. control). Three and ten additional days of retail shelf life were observed for steaks from LL7 and LL14, respectively. AP increased efficiently the retail shelf life of beefsteaks, but did not affect meat tenderness. The extended ageing from 7 to 14 days also induced higher tenderness in beefsteaks and did not show any affect negative effect on other quality parameters. Innovative technology referring to ageing under vacuum combined with Hi-O2 MA/AP would be desirable for beefsteaks during display and constituted a good alternative for meat supermarkets.

The Effect of Extensive Feeding Systems on Growth Rate, Carcass Traits, and Meat Quality of Finishing Lambs

This review aims to summarize the relevant published information about the effects of extensive feeding systems on the carcass and meat quality characteristics of lambs. Lambs finished in a feedlot or with supplementation under extensive systems exhibit faster growth rates, achieve target weights quicker, and produce heavier carcass weights when compared to grazing lambs. However, the literature also shows that finishing lambs on high-quality pasture can produce satisfactory growth rates without compromising carcass and meat quality traits. Lately, the consumer demand for products perceived as "healthy" and that are produced where animal welfare is optimal under systems which do not impact negatively on the environment, has heightened the interest in lamb production under extensive systems. Lambs raised on pasture can meet many of these specifications. Also, lambs fed higher quality green pasture can produce meat with greater amounts of health-claimable omega-3 fatty acids such as eicosapentaenoic acid plus docosahexaenoic acid than feeding systems based on feedlot pellets, grain, or dry pasture/straw. It is apparent that in some previous published research, the number of animals allocated for each treatment, and the lack of replicates, makes it difficult to formulate a correct understanding of the effect of forages on lamb carcass and meat quality. Future research should concentrate on the effect of legume, improved pasture, and specialized forage finishing systems on growth rate, carcass traits, and nutritional value of meat using well-designed experiments with an adequate number of lambs and appropriate paddock replicates per treatment.

Genome-wide association study identifies loci and candidate genes for meat quality traits in Simmental beef cattle

Improving meat quality is the best way to enhance profitability and strengthen competitiveness in beef industry. Identification of genetic variants that control beef quality traits can help breeders design optimal breeding programs to achieve this goal. We carried out a genome-wide association study for meat quality traits in 1141 Simmental cattle using the Illumina Bovine HD 770K SNP array to identify the candidate genes and genomic regions associated with meat quality traits for beef cattle, including fat color, meat color, marbling score, longissimus muscle area, and shear force. In our study, we identified twenty significant single-nucleotide polymorphisms (SNPs) (p < 1.47 × 10(-6)) associated with these five meat quality traits. Notably, we observed several SNPs were in or near eleven genes which have been reported previously, including TMEM236, SORL1, TRDN, S100A10, AP2S1, KCTD16, LOC506594, DHX15, LAMA4, PREX1, and BRINP3. We identified a haplotype block on BTA13 containing five significant SNPs associated with fat color trait. We also found one of 19 SNPs was associated with multiple traits (shear force and longissimus muscle area) on BTA7. Our results offer valuable insights to further explore the potential mechanism of meat quality traits in Simmental beef cattle.

A Contribution of Beef to Human Health: A Review of the Role of the Animal Production Systems

Meat and meat products constitute important source of protein, fat, and several functional compounds. Although beef consumption may implicate possible negative impacts on human health, its consumption can also contribute to human health. Quality traits of beef, as well as its nutritional properties, depend on animal genetics, feeding, livestock practices, and post mortem procedures. Available data show that emerging beef production systems are able to improve both, quality and nutritional traits of beef in a sustainable way. In this context, Argentina's actions are aimed at maximising beef beneficial effects and minimising its negative impact on human health, in a way of contributing to global food security.

Colour Changes in Meat of Foals as Affected by Slaughtering Age and Post-thawing Time

The aim of the present work was to investigate how colour changes of foal meat can vary after thawing out in relation to the slaughtering age of the horses and to the post-thawing time. Eighteen Italian Heavy Draught Horse (IHDH) foals were used for the trial. They were subdivided in three groups according to their slaughtering age (6, 11 and 18 months). Two different surfaces were investigated for each sample: a fresh cut surface (daily renewed cutting surface: DRCS), and not-renewed cutting surface (NRCS). The redness of both investigated surfaces increased with slaughtering age (p<0.01). Moreover, this parameter decreased during post-thawing time (p<0.01) only on the NRCS, probably due to the myoglobin oxidation processes. Colour is an important visual cue denoting perceived quality by consumers. So, by a chromatic perspective the thawed meat of IHDH foals slaughtered at 6 and 11 months proved to be that which best meets the market requirements.

Carcass Characteristics and Meat Quality of Swamp Buffaloes (Bubalus bubalis) Fattened at Different Feeding Intensities

Twenty-four male 1-year old swamp buffaloes (Bubalus bubalis) were randomly allocated to 4 groups. One group grazed on guinea grass (GG) and another on guinea grass and the legume Stylosanthes guianensis (GL). The other two groups were kept in pens and fed freshly cut guinea grass and concentrate at an amount of 1.5% (GC1.5) and 2.0% (GC2.0) of body weight, respectively. The effect of the different feeding intensities on carcass characteristics and meat quality were assessed. The mean body weight at slaughter was 398 (±16) kg. Average daily gain was higher in concentrate-supplemented groups (570 and 540 g/d in GC1.5 and GC2.0, respectively) when compared to GG (316 g/d) and GL (354 g/d) (p<0.01). Likewise, the warm carcass weight was higher in GC1.5 and GC2.0 compared to GG and GL. Dressing percentage was 48.1% and 49.5% in GC1.5 and GC2.0 in comparison to 42.9% and 44.8% observed in GG and GL, respectively. Meat of Longissimus throracis from GC1.5 and GC2.0 was redder in color (p<0.01), while water holding capacity (drip and thawing loss) was improved in pasture-fed groups (p<0.05). Protein and fat content of Longissimus thoracis was higher in animals supplemented with concentrate (p<0.01), as was cholesterol content (p<0.05), whereas PUFA:SFA ratio was higher and n-6/n-3 ratio lower (p<0.01) in pasture-fed buffaloes. Results of the present study showed that the supplementation of pasture with concentrate enhances the growth and carcass characteristics of swamp buffaloes expressed in superior dressing percentage, better muscling, and redder meat with a higher content of protein and fat, whereas animals grazing only on pasture had a more favorable fatty acid profile and water holding capacity. In conclusion, the supplementation of concentrate at a rate of about 1.5% of body weight is recommended to improve the performance and carcass quality of buffaloes.

Effect of two Spanish breeds and diet on beef quality including consumer preferences

BACKGROUND

Farmers in dry mountain areas are changing their management strategies to improve livestock farming efficiency, by using different forages or different breeds. The effect of breed (Parda de Montaña vs. Pirenaica) and finishing diet (grazing on meadows vs. a total mixed ration (50% alfalfa, 40% maize grain, 10% straw)) on carcass characteristics and meat quality of steers was studied.

RESULTS

Parda de Montaña had a greater (P < 0.01) amount of intramuscular fat than Pirenaica. The finishing diet did not influence carcass fat color, but fatty acid composition was slightly affected. Finishing steers on a total mixed ration increased the percentage of fat of the 10th rib (P < 0.001). Supplementation with concentrates increased the diet energy concentration and also increased the dressing percentage.

CONCLUSIONS

Both breeds had similar carcass characteristics. Consumers preferred beef from the Pirenaica breed because of its greater tenderness. Consumers did not differentiate between beef from animals fed different finishing diets. However, consumers who like meat very much preferred meat aged in a cooler at 4 °C for 15 days rather than 8 days.

Conjugated linoleic acid and betain prevent pork quality issues from diets containing distillers’ dried grains with solubles

Su, B., Wang, L., Wang, H., Shi, B., Shan, A. and Li, Y. 2013. Conjugated linoleic acid and betain prevent pork quality issues from diets containing distillers’ dried grains with solubles. Can. J. Anim. Sci. 93: 477–485. An experiment was conducted to evaluate the effects of conjugated linoleic acid (CLA) or betaine (BET) in diets containing distillers’ dried grains with solubles (DDGS) on the fatty acid profile and the shelf-life attributes of pork. Thirty-two (60±2 kg) crossed-bred barrows (Duroc×Landrace×Yorkshine) were randomly assigned to one of four diets: (1) the control diet containing no corn DDGS (control group); (2) the diet containing 30% corn DDGS (DDGS-fed group); (3) the diet containing 30% corn DDGS and 10 g kg−1 CLA (CLA-fed group); (4) the diet containing 30% corn DDGS and 1 g kg−1 BET (BET-fed group). Dietary DDGS decreased the proportion of saturated fatty acids (SFA) (P<0.05), and increased the proportion of unsaturated fatty acids (UFA) and polyunsaturated fatty acids (PUFA) (P<0.05) in pork with respect to the control group, whereas dietary CLA and BET decreased the proportion of PUFA and increased the proportion of SFA in pork compared with DDGS-fed group. Pork treated with DDGS alone had higher total volatile basic nitrogen (TVB-N) value (P<0.05) and thiobarbituric acid reactive substances (TBARS) value (P<0.05) with respect to the control diet during display, whereas CLA-fed group and BET-fed group had lower TVB-N concentration and TBARS value (P<0.05) in pork than DDGS-fed group. There was no significant difference of instrumental color (L*, a*, b*) between DDGS-fed group and the control group (P>0.05). However, CLA-fed and BET-fed groups maintained lower L* values and higher a* values (P<0.05), but did not affect b* values with respect to the DDGS-fed group and the control group. Results confirmed that diets containing 30% DDGS have some adverse effects on pork freshness and lipid peroxidation; However, supplementation with CLA or BET can partially reverse these effects and improve color image of pork during display.

Concentration of antioxidants in two muscles of mature dairy cows from Azores

This study evaluated the concentrations of α-tocopherol, β-carotene, creatine, carnosine, anserine and coenzyme Q10 in Longissimus dorsi (Ld) and Gluteus medius (Gm) muscles of culled dairy cows and the impact of age, production status before slaughter (dry-off vs lactating) and carcass weight on them. The effects of applying a finishing feeding regimen before slaughter were also examined. Gm muscle presented higher levels (P<0.001) of α-tocopherol (5.14 vs 3.61 μg · g(-1)) β-carotene (0.36 vs 0.27 μg · g(-1)), anserine (59.24 vs 43.25 mg · 100 g(-1)) and coenzyme Q10 (3.33 vs 1.73 mg · 100 g(-1)), and by contrast lower (P<0.05) creatine concentration (502.40 vs 527.28 mg · 100 g(-1)) than Ld. Dry-off and lactating cows differed significantly in α-tocopherol level (P<0.001) but not in the concentrations of the other compounds (P>0.05). The finishing feeding promoted higher mean concentrations of anserine and creatine but lower carnosine values (P>0.05) than directly slaughtered dry-off cows. The variation between muscles and from animal-to-animal makes it difficult to exactly define the antioxidant status of the dairy cow's meat.

Influence of different production strategies on the stability of color, oxygen consumption and metmyoglobin reducing activity of meat from Ningxia Tan sheep

Fifty male Ningxia Tan sheep were randomly divided into five groups (10 per group). Different feeding strategies were applied to each group for 120 days prior to slaughter. The sheep belong to five groups were pastured for 0 h (feedlot-fed), 2h, 4h, 8h, 12h per day on a natural grazing ground, respectively. M. semitendinosus muscle from Tan sheep was obtained after slaughter. Instrumental color, pH values, oxygen consumption rate, metmyoglobin reducing activity and relative metmyoglobin percentages were analyzed after 1, 3, 5, 7 and 9 days of refrigerated storage. Long-term daily grazing and herbage-based diet were conducive to maintain a lower oxygen consumption rate, higher metmyoglobin reducing activity and lower metmyoglobin accumulation. The combination of pasture-fed and feedlot-fed was conducive to weight gain, and at the same time, increased the color stability of the meat from Ningxia Tan sheep.