Effects of feeding legume-grass pasture and different concentrate levels on fatty acid profile, volatile compounds, and off-flavor of the M. longissimus thoracis

Effect of different botanically-diverse diets on the fatty acid profile, tocopherol content and oxidative stability of beef

BACKGROUND

Beef from pasture-fed animals is viewed as a healthier and more welfare-friendly alternative to concentrate-fed beef. Botanically-diverse pastures consisting of numerous plant species may alter the fatty acid (FA) profile and the tocopherol content of beef, as well as the oxidative stability of the meat. In the present study, steers were assigned to one of three botanically-diverse diets: perennial ryegrass (PRG), perennial ryegrass + white clover (PRG + WC) or multi-species (MS), all with a finishing diet of the respective botanically-diverse silages plus a cereal-based concentrate, consistent with production systems in Ireland. The FA profile, tocopherol content, oxidative stability and colour of meat during storage were measured.

RESULTS

Compared to the other diets, the MS diet resulted in higher proportions of linolenic acid (C18:3n-3c), linoleic acid (C18:2n-6c) and total polyunsaturated fatty acids (PUFA), with higher PUFA:saturated fatty acid and n-6:n-3 ratios in the meat. α-Tocopherol concentrations were lowest in the meat of animals from the MS diet. In uncooked meat, lipid oxidation and colour values were affected by storage time across all diets, whereas the MS diet led to higher hue values only on day 14 of storage. When cooked, meat from animals on PRG + WC and MS diets had higher lipid oxidation on days 1 and 2 of storage than meat from animals on the PRG diet.

CONCLUSION

Feeding steers on a botanically-diverse diet consisting of six plant species can improve the n-3 FA and PUFA concentration of beef, affecting the susceptibility of cooked, but not uncooked, beef to oxidation. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Effects of substituting noug seed cake with pigeon pea leaves or desmodium hay on performance of male dairy calves

This experiment was conducted to evaluate the effects of substituting 50% of noug seed cake (NSC) in a concentrate mixture with pigeon pea leaves (PPL) or desmodium hay (DH) on feed intake, digestibility, body weight gain, carcass composition, and meat quality of crossbred male dairy calves. Twenty-seven male dairy calves at 7-8 months of age with an average initial body weight of 150 ± 31 kg (mean ± SD) were assigned to 3 treatments in a randomized complete block design with 9 replications. Calves were blocked based on their initial body weight and assigned to the 3 treatments. All calves were fed native pasture hay ad libitum (at ⁓10% refusal) supplemented with a concentrate containing 24% NSC (treatment 1) or supplemented with a concentrate where 50% of NSC was replaced with PPL (treatment 2) or a concentrate where 50% of NSC was replaced with DH (treatment 3). Feed and nutrient intake, apparent nutrient digestibility, body weight gain, feed conversion ratio, carcass composition, and meat quality (except texture) were similar (P > 0.05) among treatments. Treatments 2 and 3 had more (P < 0.05) tender loin and rib meat than treatment 1. It can be concluded that 50% of NSC in the concentrate mixture can be replaced with either PPL or DH in growing male crossbred dairy calves to achieve similar growth performance and carcass characteristics. Since the substitution of 50% NSC either with PPL or DH resulted in similar outcomes in almost all responses measured, it is recommended to evaluate the complete substitution of NSC either with PPL or DH on the performance of calves.

Can botanically-diverse pastures positively impact the nutritional and antioxidant composition of ruminant meat? - Invited review

A desire for more sustainable pasture-based ruminant feeding systems has led to growing interest in utilising botanically-diverse pastures (BDP) over monoculture pastures. Research suggests that, from a human consumption viewpoint, grass-based ruminant feeding leads to more nutritionally desirable fatty acid (FA) and antioxidant concentrations in meat compared with concentrate feeding, which can affect meat quality. The FA, antioxidant and secondary metabolite content of plants differ, depending on species, maturity and seasonality, offering the potential through targeted feeding of BDP to produce meat with superior nutritional and antioxidant profiles. This review explores the effect, if any, that grazing ruminants on BDP has on the FA profile, fat-soluble vitamin, and antioxidant content of meat. The input-output relationship between forage and red meat constituents is complex and is likely affected by species diversity, forage consumption patterns and modulation of rumen fermentation processes. Further investigation is required to fully understand the effect that BDP may have on the composition and quality of ruminant meat.

Identification and Inhibition of the Key Off-Odorants in Duck Broth by Means of the Sensomics Approach and Binary Odor Mixture

To improve the sensory quality and promote the diversified development of duck meat, the identification and inhibition of key off-odorants in duck broth were comparatively characterized by using the sensomics approach and binary odor mixture analysis. Sensory evaluation results showed that Litsea pungens Hemsl (LPH) could strongly inhibit the duck broth off-odorants. Fifty-four aroma-active compounds with flavor dilution factors ranging from 1 to 2048 were identified in duck broth and duck broth stewed by LPH. Recombination and omission tests confirmed that trans-4,5-epoxy-(E)-2-decenal, (E)-2-octenal, p-cresol, 1-octen-3-ol, and 4-methyloctanoic acid were the key off-odorants in duck broth. Additionally, trans-4,5-epoxy-(E)-2-decenal (9.26 μg/L) and p-cresol (718.91 μg/L) were identified as the key off-odorants in duck meat for the first time. The results of binary odor mixture and off-odorants inhibition curves demonstrated that linalool with the lowest theoretical inhibitory concentration (109.65 μg/L) had the best aroma masking ability among the five off-odorants, followed by geraniol (123.03 μg/L), (Z)-3,7-dimethyl-2,6-octadien-1-ol (301.99 μg/L), (E)-3,7-dimethyl-2,6-octadienal (2187.76 μg/L), and (Z)-3,7-dimethyl-2,6-octadienal (2691.53 μg/L). The spiking test verified that these compounds with the lowest theoretical inhibitory concentrations effectively inhibited the off-odorants of duck broth.

Effects of Different Dietary Carbohydrate Sources on the Meat Quality and Flavor Substances of Xiangxi Yellow Cattle

This study investigated the dietary supplementation of starches with different carbohydrate sources on the proximate composition, meat quality, flavor substances, and volatile flavor substances in the meat of Chinese Xiangxi yellow cattle. A total of 21 Chinese Xiangxi yellow steers (20 ± 0.5 months, 310 kg ± 5.85 kg) were randomly divided into three groups (control, corn, and barley groups), with seven steers per group. The control steers received a conventional diet (coarse forage type: whole silage corn at the end of the dough stage as the main source), the corn group received a diet with corn as the main carbohydrate source, and the barley group received a diet with barley as the main carbohydrate source. The experiment lasted for 300 d. and the means of the final weights in the control, corn, and barley groups were 290 kg, 359 kg, and 345 kg. The diets were isonitrogenous. The corn and barley groups reduced the moisture (p = 0.04) and improved the intramuscular fat content of the meat (p = 0.002). They also improved meat color (a*) (p = 0.01) and reduced cooking loss (p = 0.08), shear force (p = 0.002), and water loss (p = 0.001). There was no significant difference in the 5′-nucleotide content (p > 0.05), the equivalent umami concentration (EUC) (p = 0.88), and taste activity value (TAV) (p > 0.05) among the three groups. The 5′-IMP (umami) content was the highest in the 5′-nucleotide and its TAV > 1. The corn and barley groups improved the content of tasty amino acids (tAA, p < 0.001). The corn group had a higher content of sweet amino acids (SAA, p < 0.001) and total amino acids (TAA, p = 0.003). Corn and barley improved the levels of MUFA (p < 0.001), PUFA (p = 0.002), n-3 PUFA (p = 0.005), and n-6 PUFA (p = 0.020). The levels of alcohols, hydrocarbons, and aldehydes in the corn group were higher than in the barley and control groups (p < 0.001). The esters content in the corn group was higher than in the barley and control groups (p = 0.050). In conclusion, feeding corn or barley as a carbohydrate source can improve the nutrient content and taste. Feeding corn as a carbohydrate source can improve the content of free amino acids (Cys, Glu, Gly, Thr, Leu, Trp, Gln, Asn, and Asp), fatty acids (saturated fatty acid, monounsaturated fatty acid, polyunsaturated fatty acid, n-3PUFA, n-6PUFA, and total fatty acid), and volatile flavor substances (alcohols, aldehydes, acids, and hydrocarbons) to improve the flavor and meat quality.

Comparison and analysis on sheep meat quality and flavor under pasture-based fattening contrast to intensive pasture-based feeding system

Objective

The objective of this study was to investigate the effect of 4-month intensive feeding on the meat quality, fatty acid profile, flavor, and growth performance of grazing Hulunbuir sheep (HBS).

Methods

The HBS were selected 4-months after birth in a pasture rearing system as the experimental animals (n = 44, female, average body weight 23.8±2.2 kg) then divided equally into pasture-based grazing fattening (PAS) and concentrate-included intensive fattening (CON) groups for another 4-month finishing. When finished fattening, all animals were slaughtered to collect musculus longissimus dorsi subcutaneous adipose tissue and to investigate the influences on meat quality, fatty acid profile, flavor and growth performance.

Results

The results showed lambs in CON group got significantly higher live weight, hot carcass weight, and dressing percentage. The CON group had significantly higher value of redness (a*), lightness (L*) and water holding capacity (p<0.05), significantly lower value of Warner-Bratzler shear force than the PAS group (p<0.05). The subcutaneous fat from CON group lambs demonstrated a significantly higher content of C18:1 and C18:2 (p<0.05), but lower C14:0 and C16:0, indicating an increased degree of unsaturated fatty acid. The content of 4-methyloctanoic acid, 4-ethyloctanoic acid and 4-methylnonanoic acid had increased 2 to 4 times, representing a more intense odor in the CON group. However, the values were still lower than most sheep breeds reported, indicating the indoor feeding system could not fundamentally deteriorate the excellent meat characteristic of HBS.

Conclusion

It was evident that lambs in CON group exhibited a better meat production performance, improved in meat color, texture and healthier fatty acid profile through pasture-weaned concentrate included intensive fattening system, which offers a good alternative regimen for lamb finishing and has a wide prospection in the HBS meat industry.

Influence of beef genotypes on animal performance, carcass traits, meat quality, and sensory characteristics in grazing or feedlot-finished steers

A 2-yr study was conducted to evaluate the effects of beef genotypes and feeding systems on performance, carcass traits, meat quality, and sensory attributes. A 2×2 factorial experiment was used to randomly allocate 60 steers in year 1 (YR1) and 44 steers in year 2 (YR2). The two beef genotypes evaluated were Red Angus (RA), and RA x Akaushi (AK) crossbreed. The steers were allotted to two finishing feeding systems: grazing, a multi-species forage mixture (GRASS) and feedlot finishing, conventional total mixed ration (GRAIN). All steers were slaughtered on the same day, at 26 and 18 mo of age (GRASS and GRAIN, respectively), and carcass data were collected 48 h postmortem. Growth and slaughter characteristics were significantly impacted by the finishing system (P < 0.01), with the best results presented by GRAIN. Beef genotype affected dressing percent (P < 0.01), ribeye area (P = 0.04), and marbling score (P = 0.01). The AK steers had a tendency (P = 0.09) for lower total gain; however, carcass quality scores were greater compared to RA. There was a genotype by system interaction for USDA yield grade (P < 0.01), where it was lower in GRASS compared to GRAIN in both genotypes, and no difference was observed between the two genotypes for any GRASS or GRAIN systems. There was no difference in meat quality or sensory attributes (P > 0.10) between the two genotypes, except that steaks from AK tended to be juicier than RA (P = 0.06). Thawing loss and color variables were impacted by the finishing system (P < 0.01). L* (lightness) and hue angle presented greater values while a* (redness), b* (yellowness), and chroma presented lower values in GRAIN compared to GRASS. Sensory attributes were scored better in GRAIN than GRASS beef (P < 0.01). There was a genotype by system interaction for flavor (P = 0.02), where beef from RA had a lower flavor rating in GRASS than in GRAIN, and no difference was observed for AK. Within each system, no difference was observed for flavor between RA and AK. Beef from steers in GRASS had greater (P < 0.01) WBSF than those from GRAIN. These results indicate that steers from GRAIN had superior performance and carcass merit and that AK enhanced these traits to a greater degree compared to RA. Furthermore, the beef finishing system had a marked impact on the steaks’ sensory attributes and consumer acceptability. The favorable results for texture and juiciness in GRAIN, which likely impacted overall acceptability, may be related to high marbling.

Fatty Acid Composition and Volatile Profile of longissimus thoracis&nbsp;et&nbsp;lumborum Muscle from Burguete and Jaca Navarra Foals Fattened with Different Finishing Diets

The present study evaluated the effect of breed, Jaca Navarra (JN) vs. Burguete (BU), and finishing diet, conventional concentrate—diet 1 (D1) vs. silage and organic feed—diet 2 (D2), on the fatty acid composition and volatile profile of longissimus thoracis et lumborum muscle from forty-six foals. For this, foals were reared under a semi-extensive system and slaughtered at about 21 months of age. The outcomes showed that breed and finishing regime had a significant (p < 0.05) effect on the lipid and volatile profile of foal meat. In particular, JN foals reported higher polyunsaturated fatty acid contents and better nutritional indices in line with the health guidelines; whereas, BU and D1 groups generated higher amounts of total volatile compounds. However, it was the diet to occupy a central role in this study. Indeed, diet 2, due to its “ingredients” and composition, not only ameliorated the lipid profile of foal meat, but also reduced the generation of volatile compounds associated with lipid oxidation and minimized off-flavors. Thus, this diet could give an added value to the aromatic perception of meat and improve its sensorial acceptability.

Fatty Acid Composition of Meat Animals as Flavor Precursors

This article provides an overview of fatty acids in meat, their variation among animal species, and the roles of fatty acids as flavor precursors. Animal fat mostly consists of triglycerides and phospholipids. Fats from ruminant (cattle, sheep, and goats) and monogastric (pigs and horses) animals have similar fatty acids with more saturated fatty acids and monounsaturated fatty acids than polyunsaturated fatty acids. In monogastric animals, fatty acids in the muscle reflect the composition of diets, whereas ruminant fatty acids are more saturated because of biohydrogenation in the rumen. Lipid- derived flavor compounds are formed from the thermal oxidation of fatty acids during cooking, producing more desirable aromatic compounds than autoxidation. Monounsaturated fatty acids such as oleic acid and polyunsaturated fatty acids such as linoleic acid in meat produce various volatile compounds contributing to cooked meat aromas. Under most cooking conditions, lipid-derived flavor compounds are usually predominant. However, these compounds have greater thresholds than those derived from water-soluble compounds, such as the Maillard reaction products. The interactions between lipid oxidation products and Maillard compounds are more important for the development of meat flavor than originally thought. Moreover, fat-derived volatile compounds provide flavor notes indicative of species identification.

Influence of the Production System (Intensive vs. Extensive) at Farm Level on Proximate Composition and Volatile Compounds of Portuguese Lamb Meat

Today’s society demands healthy meat with a special emphasis on integrated animal husbandry combined with the concern for animal welfare. In this sense, the raising of lambs in an extensive system has been one of the most common practices, which results in meats with high nutritional value. However, both the production system and the diet play a fundamental role in the chemical composition of the meat, which has a direct impact on the content of volatile compounds. Thus, the aim of this study was to determine the effect of two production systems (intensive and extensive) on the chemical composition and volatile profile of lamb meat. Twenty-eight lambs of the Bordaleira-de-Entre-Douro-e-Minho (BEDM) sheep breed were raised for meat production under the intensive or extensive system and were fed with concentrate and pasture, respectively. All animals were carried out in the muscle longissimus thoracis et lumborum. Results evidenced that all the composition parameters were affected by the production system. Extensively-reared lambs produced meat with the highest fat and protein contents, while these animals had the lowest percentages of moisture and ash. Similarly, the total content of volatile compounds was affected (p < 0.05) by the production system and were higher in the meat of lambs reared extensively. Furthermore, the content of total acids, alcohols, aldehydes, esters, ethers, furans and sulfur compounds as well as most of the individual compounds were also affected (p < 0.05) by the production system, whereas total hydrocarbons and ketones were not affected (p > 0.05). As a general conclusion, the production system had very high influence not only in proximate composition but also in the volatile compounds.

Effects of Age and Rice Straw Inclusion Levels in the Diet of Yiling Cull Cows on Growth Performance, Meat Quality, and Antioxidant Status of Tissues

Simple Summary

Several negative attributes are associated with carcass and meat from cull cows, including lower carcass weights, inferior tenderness, etc. These undesirable characteristics are normally more distinct with increasing age. In addition, there are no recommended standards for forage levels in the diet of Chinese local cattle to produce high marbled beef. In the current study, we evaluated the effects of age and forage levels on the finishing performance of Yiling cull cows under high-energy ration conditions, and also investigated their antioxidant status related to age and diet. We found that younger age and adequate forage had better growth performance and carcass traits. Our findings highlight the importance of selecting according to age and providing adequate forage feed for Yiling cull cows. Moreover, our study also demonstrated the excellent capability of producing high marbled beef for Yiling cattle.

Abstract

The objectives of this study were to investigate the effects of age and dietary straw levels on growth performance, carcass and meat traits, as well as tissue antioxidant status of Yiling cull cows. Twenty-four Yiling cull cows were arranged in a 2 × 2 factorial design: two age classes consisting of younger cull cows (YCC; appearing with three or four pairs of permanent teeth) and older cull cows (OCC; worn out teeth); two dietary treatments consisting of lower and higher rice straw levels (LRS and HRS; providing 0.7 kg/d and 1.2 kg/d rice straw per head based on air-dry basis, respectively). Cows were fed twice a day. Straw was offered at half of the predetermined weight each meal; concentrate was separately supplied ad libitum. After 300 d of feeding, final body weight (BW), total BW gain, average daily gain and gain:feed intake were higher (p < 0.01) in the YCC group than in the OCC group. Total dry matter intake was higher (p = 0.03) in the HRS group than in the LRS group, but neutral detergent fiber apparent digestibility was negatively affected (p = 0.01) by increased straw levels. Decreased C15:0, C17:0, C20:5n3c, and saturated fatty acids (SFAs) proportion as well as increased C18:1n9c and monounsaturated fatty acids (MUFAs) proportion in meat from YCC with HRS diet were observed as compared to that in meat from YCC with LRS diet (p < 0.05). Meat from HRS group had higher (p = 0.04) C18:3n3c proportion than meat from LRS group. No significant differences (p > 0.05) were found for meat quality attributes except for cooking loss, which was higher (p = 0.02) in the HRS group than in the LRS group. Both YCC group and HRS group had higher (p < 0.05) cold carcass weight compared to OCC group and LRS group. Moreover, catalase activity of liver tissue was higher (p = 0.045) in YCC than in OCC, while superoxide dismutase activity of muscle tissue was higher (p = 0.01) in LRS than in HRS. Based on results, we concluded that younger age and feeding high-level straw can improve the finishing performance of Yiling cull cows.

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.

Volatile Compounds, Odour and Flavour Attributes of Lamb Meat from the Navarra Breed as Affected by Ageing

This study aimed to assess the influence of ageing on the volatile compounds, as well as odour and flavour attributes of lamb meat from the Navarra breed. Twenty-one male lambs were fed a commercial concentrate diet after weaning and were harvested at 101 ± 6.5 days of age. From the Longissimus thoracis, 26 volatile compounds were identified, with hexanal, 2-propanone, and nonanal the most abundant (57.17% relative percentage abundance, RPA). The effect of ageing (1 vs. 4 d) was observed (p < 0.05) in six compounds: 1,4-dimethylbenzene decreased with ageing, while tridecane, 3-methylbutanal, 2-heptanone, 3-octanone, and 1-octen-3-ol increased. In general, ageing was linked to a decrease in livery and bloody flavour, bloody odour and ethanal, and an increase in pentane, hexanal, and heptanal, which are usually associated with fresh green grass and fat descriptors. Consequently, ageing lamb from the Navarra breed for four days might have a positive effect on meat sensory odour and flavour quality.

Protected or Unprotected Fat Addition for Feedlot Lambs: Feeding Behavior, Carcass Traits, and Meat Quality

Simple Summary

The use of lipids in ruminant diets aims to increase energy density without affecting the animal’s performance; however, its use can be toxic to the ruminal microbiota, which can be avoided with the use of protected fats. Diets with the inclusion of different fat sources (whole soybean grain, corn germ, calcium salt of fatty acids, and soybean oil) were tested to evaluate the effects of unprotected or protected fats on feeding behavior, carcass characteristics, and quality of the meat of feedlot lambs. The use of calcium salts from fatty acids in feedlot lambs’ diets improves the quantitative and qualitative characteristics of the carcass and meat.

Abstract

This study aimed to evaluate the effect of the inclusion of protected or unprotected fats in the diet of feedlot lambs on feeding behavior, productive characteristics, carcass traits, and meat quality. Forty male Dorper × Santa Inês lambs (22.27 ± 2.79 kg) were randomly assigned to treatments in a completely randomized design. The experimental treatments consisted of five diets: no added fat (NAF), whole soybeans (WSB), calcium salts of fatty acids (CSFA), soybean oil (SO), and corn germ (CG). The total intake of dry matter (DMI) (p < 0.001) and neutral detergent fiber (NDFI) (p = 0.010) were higher in the CSFA and NAF diets. Feeding behavior, morphometric measurements, physicochemical characteristics, and centesimal composition of the Longissimus lumborum muscle were similar between treatments (p > 0.05). The CSFA diet provided higher production (p < 0.05) and better-quality carcasses. The inclusion of fat sources increased the concentration of polyunsaturated fatty acids (p < 0.05). The use of calcium salts of fatty acids in feedlot lambs’ diets provides better quantitative and qualitative characteristics of the meat and carcass.

Effects of grass- and concentrate-based finishing systems on the quality of meat from the M. longissimus thoracis of young Sarda bulls

Context Recent heightened interest of consumers in the origins of their food, together with broader general awareness of environmental matters, has led to an increase in the demand for meat obtained from grazing systems. The importance of local breeds adapted to medium- and low-input production is fully recognised as a means of guaranteeing the sustainability of these farming methods. A finishing system based on pastures and the use of local breeds could both meet the demands of consumers and increase economic returns for Sardinian farmers. Aims The work evaluated the effects of different finishing treatments (pasture PAS-0C vs hay–concentrate-based diets HAY-C) on the quality of meat from young Sarda bulls and the usefulness of meat chemicals as markers to discriminate between finishing systems. Methods Twenty-eight young Sarda bulls were assigned randomly to the following two treatments: finished on natural pasture (PAS-0C group, n = 7), and fed on natural pasture hay ad libitum and concentrate (HAY-C group, n = 21). The latter group comprised three levels characterised by an increasing daily dose of concentrates, as follows: 2.5 kg/animal (HAY-2.5C), 3.3 kg/animal (HAY-3.3C), and ad libitum (HAY-ALC). After slaughter at a fixed age (416 ± 25 days), carcass yield, pH of the Longissimus thoracis (LT) muscle, colour parameters, cooking loss, proximate analysis, α-tocopherol and cholesterol concentration, and fatty acid composition of intramuscular fat of LT were all determined. The discriminating power of the meat chemicals between the two main finishing systems (PAS-0C vs HAY-C) and among the three groups receiving concentrates and hay (HAY-2.5C, HAY-3.3C and HAY-ALC) was assessed using linear discriminant analysis. Key results Pasture-based treatment decreased the intramuscular fat and increased the α-tocopherol concentration of meat and the proportion of some desirable fatty acids (α-linolenic acid and its derivatives eicosapentaenoic acid, docosapentaenoic acid), and improved the value of the ratio of n-6:n-3, without affecting the ultimate pH, colour parameters, and cooking loss. The discriminant procedure was able to discriminate accurately between the two main finishing systems and among the three groups receiving concentrate and hay (P &lt; 0.0001 and P &lt; 0.005 of the Hotelling’s T-squared test respectively). The concentration of α-tocopherol was key to the discrimination of the two main finishing systems, whereas the content of C17:0 and C18:0i were particularly effective in discriminating among the three groups fed with hay concentrate. Conclusions Grazing improves some of the meat traits of young Sarda bulls compared with the effects of a hay-concentrate-based finishing diet. The concentration of α-tocopherol in meat is an effective marker for discriminating the effects of pasture from those of a concentrate-based finishing diet Implications The results highlight the role of pasture-based diet in finishing young Sarda bulls, and could provide a wealth of knowledge for Sardinian beef farmers for delivering meat produce that stands out in the market and meets the demand of consumers more concerned about food origin and its healthiness.

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.

Flavor Characterization of Grass- and Grain-Fed Australian Beef Longissimus Lumborum Wet-Aged 45 to 135 Days

The study objective was to evaluate the effects of extended postmortem wet aging of Australian beef, cattle diet, and their interaction on objective and subjective measures of beef flavor of the longissimus lumborum. Beef strip loins were collected from grass- and grain-fed cattle (n = 50 total) at a commercial abattoir near Brisbane, Australia. Beef longissimus lumborum were portioned and assigned randomly to one of 3 postmortem aging periods (45, 70, or 135 d). As each section reached its respective postmortem aging designation, that section was fabricated into 2.5-cm steaks, individually vacuum packaged, and frozen (−21°C). Trained panelists evaluated cooked steaks for numerous flavor attributes, tenderness, and juiciness; volatile compounds were also evaluated. Sensory scores differed (P &lt; 0.05) due to diet, whereby grain-fed samples were rated more intense (P &lt; 0.05) for beef flavor identity, fat-like, liver-like, and sweet but grass-fed samples were more intense (P &lt; 0.05) for green-hay and bitter. Juiciness, tenderness, and 4 flavor attributes (bloody/serumy, metallic, umami, and rancid) were similar (P &gt; 0.05) between diets. Extending postmortem aging from 45 to 135 d resulted in decreased beef and umami flavors (P &lt; 0.05), along with concurrent increased detection of off-flavors, such as liver-like, rancid, bitter, and sour (P &lt; 0.05). Volatile flavor compounds were more influenced by postmortem aging than diet. Increased postmortem aging time increased concentration for both lipid oxidation and Maillard-reaction–derived volatiles, resulting in the concentration of negative flavor volatile compounds rather than the absence of positive flavor compounds. Based on these results, differences existed in the flavor profile of longissimus lumborum from grass- and grain-fed beef, regardless of postmortem aging. However, aging beef strip loins 135 d is not recommended based on reduced beef flavor and increased off-flavor detection compared to samples aged 45 or 70 d postmortem.

In vitro rumen biohydrogenation of unsaturated fatty acids in tropical grass-legume rations

Aim:

The aim of this study was to evaluate the effects of various combinations of tropical grass-legume species in rations on the biohydrogenation (BH) activity of unsaturated fatty acids (FAs), C18:0 composition, and fermentation profile in an in vitro rumen system.

Materials and Methods:

Samples of the following five fodder plants were used: One species of grass (Pennisetum purpureum) and four species of tree legumes (Leucaena leucocephala, Gliricidia sepium, Calliandra calothyrsus, and Indigofera zollingeriana). The following eight experimental diets were evaluated: 50% P. purpureum + 50% L. leucocephala (LL I); 50% P. purpureum + 50% G. sepium (GS I); 50% P. purpureum + 50% C. calothyrsus (CC I); 50% P. purpureum + 50% I. zollingeriana (IZ I); 75% P. purpureum + 25% L. leucocephala (LL II); 75% P. purpureum + 25% G. sepium (GS II); 75% P. purpureum + 25% C. calothyrsus (CC II); and 75% P. purpureum + 25% I. zollingeriana (IZ II). Each ration was replicated 3 times. In vitro rumen incubation was performed for 48 h, according to the Tilley and Terry method. Determination of the FA profiles of the forage materials and rumen fluid samples was performed using gas chromatography.

Results:

The percentage of polyunsaturated FA (PUFA) in the forage materials ranged from 34.18% (P. purpureum) to 74.51% (C. calothyrsus). The percentage of monounsaturated FA (MUFA) ranged from 5.06% (P. purpureum) to 8.71% (L. leucocephala). The percentage of saturated FA (SFA) was the lowest at 19.12% (C. calothyrsus) and highest at 60.76% (P. purpureum). In vitro BH of C18:3 n-3, C18:2 n-6, C18:1 n-9, and C18 PUFA in the experimental diets ranged from 72% to 100%. The BH of C18:1 n-9 in GS I (80%) and IZ I (72%) was significantly different (p<0.05). The percentage of C18:0 was 10-50% and significantly different (p<0.05) among treatments, with the highest (of 50%) in GS II. No significant differences (p>0.05) were observed in the fermentation parameters (pH, total volatile FAs, in vitro dry matter digestibility, and in vitro organic matter digestibility) among the treatments, except in NH₃ concentration (p<0.05).

Conclusion:

The various combinations of tropical legumes do not have significant inhibitory effects on the BH of C18:2 n-6, C18:3 n-3, and C18 PUFA after in vitro incubation for 48h. Furthermore, an increase in the tropical legume ratio in the ration tends to suppress C18:0 formation after the fermentation simulation process. IZ I has the potential to reduce C18:1 n-9 (MUFA) disappearance and yield an ideal rumen fermentation profile.

High-density diet improves growth performance and beef yield but affects negatively on serum metabolism and visceral morphology of Holstein steers

The objective of this study was to evaluate the effect of different dietary densities on growth performance, carcass characteristics, meat quality, serum metabolism, ruminal papillae morphology and liver injuries of steers. For this purpose, a total of eighteen Holstein steers were randomly fed one of the three diets: high energy and protein diet (H), standard energy and protein diet (C), and low energy and protein diet (L) for 11 months fattening with three-step finishing strategy. Steers fed with H diet had higher (p < .05) average daily gain, feed efficiency, hot carcass weight, serum aspartate aminotransferase to alanine aminotransferase ratio, and monounsaturated fatty acids along with continuous low ruminal pH value, severer hepatic steatosis and ruminal papillae parakeratosis. Meanwhile, steers fed L diet increased the proportion of C20:0, C22:6n-3, saturated fatty acids and n-3 polyunsaturated fatty acids along with lower n-6 to n-3 ratio in longissimus dorsi muscle as compared to that of steers fed H diet. Dietary densities did not influence (p > .10) proximate nutrients and sensory characteristics of beef. The present study indicates that Holstein steers could achieve better growth and carcass performance under high-density diet, whereas they are under threat of visceral injuries and metabolic disorders. This study gives comprehensive relationship between productivity and animal health and suggests that a proper diet should be adopted for fattening Holstein steers in consideration of both beef quality and quantity and animal health.

Diets containing cunhã (Clitoria ternatea L.) hay and forage cactus (Opuntia sp.) meal on production and meat quality of Boer crossbred goat

The aim of this study was to evaluate the effect of association of forage cactus meal (CM) and cunhã hay (CH) on carcass traits, meat quality, and fatty acid (FA) profile of goats. Twenty-four goats were finished on diets composed with the association of CM and CH (83% CH + 17% CM, 67% CH + 33% CM, or 50% CH + 50% CM), corresponding to 60% of the total diet; the remainder was composed of 10% elephant grass and 30% concentrate. The control treatment consisted of 70% elephant grass and 30% concentrate. Carcass yield and commercial cut weight were higher in the animals fed CH and CM at any concentration (P < 0.05). Animals fed with intermediate and high CM content resulted in meat with better proportions of unsaturated FA (P = 0.0281), desirable FA (P = 0.0024), omega 6/omega 3 ratio (P = 0.0340), and hypo-/hypercholesterolemic index (P = 0.0140). The inclusion of CH and CM provided carcass yield and FA profile more favorable for consumer market and human health.

Methane emission, ruminal fermentation parameters and fatty acid profile of meat in Santa Inês lambs fed the legume macrotiloma

Context Using legumes in ruminant production system may provide benefits such as improvement in animal performance and decrease in methane (CH4) emissions, mainly based on nutritional characteristics of these plants and the presence of tannins. Macrotiloma (Macrotyloma axillare) is a tropical legume that still lacks studies regarding its effects on animal performance and CH4 emissions. Aims The objective of this experiment was to evaluate productive performance, CH4 emission, ruminal fermentation parameters, carcass characteristics and fatty acid profile of the meat from lambs fed tropical grass hay supplemented with the legume forage macrotiloma. Methods For a 90-day experimental period, 14 Santa Inês male lambs (aging 100 days; 18.06 ± 3.26 kg initial bodyweight) were allocated in individual pens and divided into two treatments: chopped aruana grass (Panicum maximum cv. Aruana) hay (CON); aruana hay supplemented with chopped macrotiloma hay at a ratio of 75:25 grass to legume (MAC). Lambs were weighed fortnightly for calculation of average daily bodyweight gain (ADG) and CH4 emission was measured on three occasions (days 28 to 32; 57 to 61; 85 to 89) using the sulfur hexafluoride (SF6) tracer technique. At the last day of CH4 collection, rumen fluid samples were collected for: determination of ammoniacal nitrogen (NH3-N) and short chain fatty acids (SCFA); ruminal protozoa count; and relative abundance determination of general bacteria (BACT); Ruminococcus flavefaciens (RUMI); Fibrobacter succinogenes (FIBRO); methanogenic archaea (METH) by real-time quantitative PCR (real-time-qPCR) analysis. Subsequently, after 16 h fasting, the animals were slaughtered; carcass characteristics were then evaluated and longissimus thoracis samples were collected for fatty acid profile analysis. Key results No significant difference (P &gt; 0.05) was observed between MAC and CON for productive performance, CH4 emission, SCFA and carcass characteristics. Reduced protozoa count and relative abundance of METH were observed for MAC (P &lt; 0.05). Conclusions Despite the lack of effects on productive performance and CH4 emission, the decreased relative abundance of METH and protozoa count indicated that macrotiloma may possibly present anti-methanogenic activity. Implications The inclusion of this legume in the diet of ruminants may affect rumen microbes and potentially decrease environmental impacts of the production system.

Effects of different antioxidants on quality of beef patties from steers fed low-moisture distillers grains

This research evaluated the effects of different antioxidants on overall quality of beef patties from steers fed distillers grains. Crossbred steers (n = 24) were fed corn, 40% Dry distillers grains plus solubles, or 40% modified distillers grains plus solubles - Dry Matter basis). Patties were made from ground chuck of individual animals and 4 antioxidant treatments were evaluated (CONTROL - no antioxidant, 0.3% ROSEMARY, 0.25% ACEROLA, and 0.6% CITRUS). Diets minimally affected quality attributes. Patties treated with ROSEMARY were shown significant lighter in color than other treatments on day 6. Patties treated with CITRUS were the reddest on days 5 and 6 of display. ACEROLA and CITRUS provided better lipid stability during display when compared to CONTROL and ROSEMARY. Treatment CITRUS reduced APC growth by 2 log when compared to all other treatments (P < 0.01). Although patties treated with CITRUS had higher off-flavor intensity, no effect was observed for overall desirability. Patties treated with 0.6% of CITRUS provided optimal overall quality.

Enhanced Omega-3 Polyunsaturated Fatty Acid Contents in Muscle and Edible Organs of Australian Prime Lambs Grazing Lucerne and Cocksfoot Pastures

The enhancement of health-beneficial omega-3 long⁻chain (≥C20) polyunsaturated fatty acid (n-3 LC-PUFA) contents in the muscle, liver, heart, and kidney of Australian prime lambs through pasture grazing and supplementation with oil infused pellets was investigated. Forty-eight first-cross prime lambs were randomly assigned into a split-plot design with pasture type as the main plot effect and pellet supplementation as a sub-plot effect in a feeding trial that lasted for nine weeks. The n-3 LC-PUFA content in Longissimus dorsi muscle of all lambs was well above the 30 mg threshold for "omega-3 source" nutrition claim under the Australian Food Standards and Guidelines. Pasture type impacted the fatty acid contents in muscle, heart, and kidney of prime lambs. Lambs grazing cocksfoot grass only had high 18:3n-3 (ALA) and n-3 LC-PUFA contents (67.1 mg/100 g and 55.2 mg/100 g, respectively) in the Longissimus dorsi muscle, which was not significantly different (p > 0.8990) from the contents of lambs grazing only lucerne. Supplementation of pellets with or without oil infusion to grazing lambs generally decreased the ALA and n-3 LC-PUFA contents and increased the n-6/n-3 ratio in the Longissimus dorsi muscle. The fatty acid content in the internal organs of grazing lambs was also affected by pellet supplementation. The liver and kidney of grazing lambs were both "good sources" (60 mg/100 g) of omega-3. The cocksfoot grass showed considerable potential for producing healthy, premium quality meat with high contents of n-3 and n-3 LC-PUFA, which may consequently enhance the omega-3 intake of Australian lamb consumers.