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1.
Animals (Basel) ; 13(7)2023 Mar 30.
Article in English | MEDLINE | ID: mdl-37048465

ABSTRACT

The study objective was to determine intake and performance of beef cattle individually offered perennial ryegrass-dominant grass silage ad libitum supplemented with 4 kg dry matter daily of, rolled barley or maize meal-based concentrate rations containing supplements of flaked field beans, flaked peas, maize dried distillers grains (MDD) or maize gluten feed (MGF) for 110 days (Experiment 1), rolled barley or rolled oats with or without supplements of flaked field beans or flaked peas for 146 days (Experiment 2), and to quantify the nitrogen balance of diets similar to those offered in Experiment 2 (Experiment 3). The protein supplements were formulated to have similar crude protein concentrations. Cereal type or protein source did not affect intake, growth, feed efficiency and carcass traits in Experiment 1 or 2. Inclusion of a legume protein supplement with barley or oats had no effect on intake or growth performance (Experiment 2), whereas their exclusion decreased nitrogen intake, plasma urea concentrations and urinary and total nitrogen excretion (Experiment 3). The feeding value of barley was similar to oats and maize meal, and flaked beans and peas were similar to MGF and MDD, as supplements to grass silage. Excluding protein ingredients from a cereal-based concentrate did not affect animal performance and reduced nitrogen excretion.

2.
Foods ; 11(24)2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36553802

ABSTRACT

Beef contains an array of conjugated linoleic acid (CLA) isomers for which positive effects have been reported in animal models of human disease. The objectives were to develop a CLA-enriched beef production system and to assess its quality. Sixty Spring-born heifers were housed in Autumn and offered unwilted grass silage and a barley/soyabean concentrate or wilted grass silage and a concentrate containing sunflower oil and fish oil. In May, both groups were offered either pasture for 22 weeks, restricted pasture and sunflower oil and fish oil for 22 weeks, or pasture for 11 weeks and restricted pasture and sunflower oil and fish oil for the final 11 weeks. The predominant CLA isomer in beef was cis9, trans11 representing on average, 80% total CLA. The modified winter diet followed by supplementation for 22 weeks resulted in beef that had a CLA concentration that was higher, at a comparable intramuscular fatty acid concentration, than previously reported. The lipid and colour stability (over 10 days in modified atmosphere packaging) and sensory characteristics were generally not negatively affected. There were minor effects on the expression of candidate genes involved in lipid metabolism. Consumption of this beef would make a substantial contribution to the quantity of CLA suggested to have a positive effect on consumer health.

3.
Animals (Basel) ; 12(18)2022 Sep 14.
Article in English | MEDLINE | ID: mdl-36139278

ABSTRACT

Carcasses from pasture-finished early-maturing (EM), rather than late-maturing (LM), breed bulls may be more suited to meet the minimum carcass fatness classification of 2+ (6.0 on a 15-point scale) required for some markets. The comparative colour and eating quality of beef from grass-fed bulls of different maturities are unknown. Sixty yearling suckler-bred bulls were assigned to a 2 (maturities: EM and LM) × 2 (finishing strategies: grass only (G0) or grass + 4.0 kg concentrate daily (GC)) factorial design. Bulls were at pasture from 7 April, concentrates were introduced (or not) 97 days later, and bulls were slaughtered at 192 d post-turnout (approximately 19 mo of age). Carcass fat scores averaged 5.02, 6.20, 6.33 and 7.30 for LMG0, LMGC, EMG0 and EMGC bulls, respectively. Muscle colour did not differ between treatments. Muscle from LM had lower intramuscular fat concentration, collagen solubility and a tendency (p < 0.1) towards lower ratings for tenderness, texture, and acceptability of 14 d aged beef. Concentrate supplementation decreased the ratings for muscle tenderness but ratings for acceptability were not affected. Achieving the minimum carcass fatness was therefore not required to produce beef of acceptable eating quality and suckler bulls can access the "grass-fed" beef market.

4.
Foods ; 11(15)2022 Jul 30.
Article in English | MEDLINE | ID: mdl-35954047

ABSTRACT

The primary objective of this study was to compare the colour of muscle from bulls finished at pasture or indoors on a high concentrate diet. The ancillary objectives were to identify possible explanations for any differences in the colour observed and the potential of muscle colour to discriminate between bull beef from different production systems. Growth, longissimus muscle colour, fibre type composition and metabolic profile were measured in late-maturing breed sired suckler bulls slaughtered at 19 months of age after 199 days at pasture (G0), 100 days indoors after 98 days at pasture (G0AL) and indoors for 199 days (AL). When compared to bulls finished indoors and offered a high concentrate ration, the carcass weight of G0 bulls was lower, their carcasses were leaner, and their longissimus muscle was similar in lightness but less red and had a lower glycolytic metabolism. The temperature at which the longissimus muscle reached pH 6.0 was lower (19.7 °C) for G0 than for G0AL (29.9 °C) and AL (31.6 °C), which did not differ. Co-variate adjustment for this variable removed the differences in redness. Adjusting the chill settings appears to be a practical strategy for abattoirs to minimise early post-mortem differences in muscle colour between lighter grass-fed and heavier concentrate-fed carcasses. The preliminary results demonstrate the potential of both L*, a*, b* values and the visible reflectance spectra of muscle to discriminate between grass- finished and concentrate-finished bull beef, but further refinement and validation of the models is required.

5.
J Sci Food Agric ; 102(1): 113-120, 2022 Jan 15.
Article in English | MEDLINE | ID: mdl-34060106

ABSTRACT

BACKGROUND: Grazed grass is an important component of the majority of beef production systems used in temperate climates. Compared to concentrate-fed beef, 'grass-fed' beef can command a premium in some markets based on perceived differences in appearance and sensory characteristics. The influence of grazed grass per se, as well as the duration of grazing, on selected sensory characteristics of beef within a heifer production system was examined. RESULTS: In general, fat from grass-fed cattle was more yellow than fat from similar cattle fed concentrates, whereas muscle from grass-fed cattle was darker than muscle from cattle fed concentrates. At the same carcass weight, muscle from grass-fed cattle had a lower fat concentration than cattle fed concentrates. In the most extreme situation examined, whereby early-maturing heifers were fed concentrates ad libitum from weaning or grazed grass/conserved grass throughout life, until slaughtered at a similar carcass weight (260 kg) and differed in age by 5 months, beef was rated similarly for tenderness and a range of flavours by a trained sensory panel. CONCLUSION: Within the range of beef heifer production systems examined, the sensory characteristics of grass-fed beef do not differ greatly from concentrate-fed beef. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Subject(s)
Cattle/metabolism , Meat/analysis , Muscle, Skeletal/chemistry , Poaceae/metabolism , Abattoirs , Animal Feed/analysis , Animals , Color , Humans , Muscle, Skeletal/metabolism , Taste
6.
Animals (Basel) ; 11(9)2021 Sep 07.
Article in English | MEDLINE | ID: mdl-34573588

ABSTRACT

This study evaluated the effects of post-grazing sward height (PGSH, 4 or 6 cm) on herbage production, its nutritive value, dry matter (DM) intake, grazing behaviour and growth of early- (EM) and late-maturing (LM) breed suckler steers (n = 72), and the subsequent effect of indoor finishing diet (grass silage + 3.8 kg concentrate DM/head daily (SC), or grass silage only (SO)) on performance and carcass traits. Animals rotationally grazed pasture for 196 days, followed by indoor finishing for 119 days. At pasture, daily live-weight gain (LWG) was 0.10 kg greater for PGSH-6 than PGSH-4, resulting in a tendency for carcass weight to be 11 kg heavier. Although EM had a 0.10 kg greater daily LWG at pasture than LM, carcass weight did not differ between the genotypes. There was a genotype × PGSH interaction for carcass fat score, whereby there was no difference between EM-4 (8.83, 15-point scale) and EM-6 (8.17), but LM-6 (7.28) was greater than LM-4 (6.33). Although concentrate supplementation during indoor finishing increased carcass weight (+37 kg) and fat score (1.75 units), the majority of steers (83% of EM and 78% of LM) achieved a commercially-acceptable carcass fat score (6.78) at slaughter in the grass-forage-only system.

7.
J Sci Food Agric ; 101(11): 4768-4778, 2021 Aug 30.
Article in English | MEDLINE | ID: mdl-33502758

ABSTRACT

BACKGROUND: Concentrate supplementation of a grass silage-based ration is a typical practice employed for indoor winter finishing of beef cattle in many temperate countries. Plant by-products, such as dried corn gluten feed (CGF), can be used to replace conventional feedstuffs in a concentrate supplement to enhance the sustainability of ruminant production systems and to improve meat quality. This study examined the chemical composition, fatty acid profile, oxidative stability and sensory attributes of beef (longissimus thoracis muscle) from steers offered grass silage and concentrate supplements containing varying levels (0%, 25%, 50%, 75%) of CGF substituted for barley / soybean meal. RESULTS: Feeding 50%CGF decreased the protein content and increased intramuscular fat in comparison with 25%CGF. Total phenol content and iron-reducing antioxidant power followed the order: 0%CGF > 50%CGF and 25%CGF > 0%CGF = 50%CGF, respectively. Compared to 0%CGF, 25%CGF and 75%CGF decreased C14:0 and increased C22:2n-6, C20:5n-3 and total n-3 polyunsaturated fatty acids whereas 75%CGF increased conjugated linoleic acids and C18:3n-3. Diet did not affect the oxidative stability and sensory attributes of beef patties. CONCLUSION: The inclusion of up to 75%CGF in a supplementary concentrate for steers increased the proportion of health-promoting unsaturated fatty acids without negatively influencing the shelf-life and eating quality of longissimus thoracis muscle. © 2021 Society of Chemical Industry.


Subject(s)
Animal Feed/analysis , Back Muscles/metabolism , Cattle/metabolism , Fatty Acids/chemistry , Glutens/metabolism , Poaceae/metabolism , Zea mays/metabolism , Animals , Back Muscles/growth & development , Cattle/growth & development , Diet/veterinary , Fatty Acids/metabolism , Hordeum/metabolism , Humans , Male , Meat/analysis , Silage/analysis , Glycine max/metabolism , Taste
8.
J Sci Food Agric ; 101(5): 1892-1900, 2021 Mar 30.
Article in English | MEDLINE | ID: mdl-32895942

ABSTRACT

BACKGROUND: The use of bulls rather than steers from the dairy herd offers a more profitable and environmentally friendly option; however, the beef eating quality from bulls is an issue of concern. This study assessed the effect of two tenderization techniques - pelvic suspension and ageing - on three different muscles of Holstein Friesian males from two different production systems. RESULTS: The results indicate that a production system based on steers slaughtered at 24 months (S24) produced beef with better eating quality than from bulls slaughtered at 19 months (B19) when tenderization techniques were not applied. Instrumental texture of longissimus thoracis and gluteus medius muscles was improved with ageing and/or pelvic suspension, with both tenderization techniques exerting greater impact on B19 meat. No differences were found in semitendinosus muscle due to suspension method, whereas ageing for longer than 14 days decreased its instrumental tenderness. Sensory results indicate that, after 14 days of ageing, panellists still preferred meat from S24, and they could differentiate between pelvic and traditional suspension. CONCLUSION: Tenderization methodologies should be optimized for each production system and muscle; however, both panel and instrumental texture results indicate that eating quality of beef from either production systems is acceptable after 14 days of ageing, or even earlier if the suspension method is applied. © 2020 Society of Chemical Industry.


Subject(s)
Food Handling/methods , Meat/analysis , Muscle, Skeletal/chemistry , Animals , Castration , Cattle , Female , Humans , Male , Taste
9.
Meat Sci ; 173: 108381, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33288361

ABSTRACT

Thirty-six steers were randomly assigned to one of three dietary treatments fed ad libitum grass silage and concentrate supplements containing either barley/soybean meal (CON), 80% DM corn (CDGS)- or 80% DM wheat (WDGS)-dried distillers' grains with solubles for 124 days pre-slaughter. Chemical and fatty acid composition, shelf-life, and eating quality of longissimus thoracis muscle were determined. Dietary CDGS and WDGS increased the proportion of conjugated linoleic acids (P < 0.05) and tended to increase C18:3n-3 (P = 0.075) and total polyunsaturated fatty acids (P = 0.060) relative to the CON. Feeding diets containing distillers' grains reduced the lipid and colour stability of fresh beef patties stored in modified atmosphere packs (MAP), with CDGS exhibiting an intermediate effect between CON and WDGS. Diet did not negatively influence the texture profile parameters and eating quality attributes of beef stored in MAP. The inclusion of CDGS or WDGS in supplementary concentrates may improve the fatty acid profile but decreased the shelf-life of beef.


Subject(s)
Cattle/physiology , Diet/veterinary , Edible Grain , Red Meat/analysis , Animal Feed/analysis , Animals , Fatty Acids/analysis , Male , Muscle, Skeletal/chemistry , Silage
10.
Foods ; 9(12)2020 Nov 27.
Article in English | MEDLINE | ID: mdl-33260946

ABSTRACT

A survey was conducted to determine the content of cyclopropane fatty acids (CPFAs) and ω-cyclohexyl fatty acids (CHFAs) by using gas chromatography- mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) techniques in various meat samples from different species, including commercial samples and complex and thermally processed products (i.e., Bolognese sauce). The CPFAs concentration (as the sum of two isomers, namely dihydrosterculic acid and lactobacillic acid) in bovine meat fat (ranging between 70 and 465 mg/kg fat) was positively related to a silage-based diet, and therefore, they are potential biomarkers for monitoring the feeding system of cattle. CHFAs, such as 11-cyclohexylundecanoic and 13-cyclohexyltridecanoic acids, were only found in lipid profiles from ruminant species, and a linear trend was observed in their content, together with iso-branched fatty acids (iso-BCFAs) deriving from ruminal fermentation, as a function of bovine meat percentage in both raw and cooked minced meat. Thus, CHFAs are potential biomarkers for the assurance of the meat species and, combined with iso-BCFAs, of the beef/pork ratio even in complex meat matrices. The proposed approaches are valuable novel tools for meat authentication, which is pivotal in the management of meat quality, safety, and traceability.

11.
Meat Sci ; 168: 108181, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32417672

ABSTRACT

This study investigated the quality composition, oxidative stability and sensory attributes of beef (longissimus thoracis, LT) from steers offered grass silage and a concentrate supplement in which barley was replaced by 40% and 80% (as-fed basis) of dried citrus pulp (DCP). Dietary treatment did not influence the antioxidant status (α-tocopherol and total phenolic contents) and activities of LT (radical scavenging activity, ferric reducing antioxidant power and iron chelating activity). Feeding DCP significantly increased the proportion of conjugated linoleic acids and polyunsaturated fatty acids in beef. Lipid and colour stability of fresh beef patties stored in modified atmosphere packs (MAP) were unaffected by dietary treatment but feeding 40% DCP reduced (P < .05) lipid oxidation in aerobically-stored cooked beef patties. Beef patties stored in MAP for up to 7 days were assessed by sensory panellists to be juicier for those fed 40% DCP compared to 0% and 80% DCP. Results indicated that substitution of barley with DCP improved the fatty acid profiles of beef without negatively influencing the eating quality of beef.


Subject(s)
Animal Feed/analysis , Citrus , Red Meat/analysis , Animal Nutritional Physiological Phenomena , Animals , Cattle/physiology , Diet/veterinary , Food Quality , Humans , Male , Meat Products/analysis , Muscle, Skeletal/chemistry , Silage
12.
J Sci Food Agric ; 100(5): 2176-2184, 2020 Mar 30.
Article in English | MEDLINE | ID: mdl-31901142

ABSTRACT

BACKGROUND: Lamb diets can alter the fatty acid (FA) profile of muscle and adipose tissue, which may affect the sensory quality and consumer acceptability of the meat. In this study, lambs received one of four pre-slaughter diets: a barley / maize / soya-based concentrate (C), supplemented with a saturated fat source (Megalac®) (SAT), or supplemented with protected linseed oil (PLO); or a by-product (citrus pulp / distillers' grain / soya-based) diet (BPR). Intramuscular FAs and adipose tissue branched-chain FAs were measured and consumer evaluation (hedonic liking and attribute intensity) was undertaken with cooked lamb. RESULTS: Compared to the other diets, the BPR diet resulted in a higher muscle concentration and a greater proportion of C18:2n-6, and greater proportions of conjugated linoleic acid (c9,t11-C18:2) and n-6 polyunsaturated FAs (PUFA), whereas the PLO diet resulted in higher muscle proportions of C18:0 and saturated FAs, higher concentrations of C18:3n-3 and n-3 PUFA, and a lower n-6 to n-3 ratio. The consumer acceptability of lamb was not affected by the pre-slaughter diets. CONCLUSION: Changes in the FA profile of lamb muscle and adipose tissue through the inclusion of sources of saturated fat, protected linseed oil, or by-products in the pre-slaughter diet did not result in consumer detection of significant effects on the acceptability of the cooked meat. © 2020 Society of Chemical Industry.


Subject(s)
Consumer Behavior , Dietary Fats , Fatty Acids/analysis , Red Meat/analysis , Subcutaneous Fat/chemistry , Adolescent , Adult , Aged , Animal Feed/analysis , Animals , Cooking , Diet/veterinary , Dietary Supplements , Female , Humans , Linoleic Acids, Conjugated/analysis , Linseed Oil/analysis , Male , Middle Aged , Sheep , Taste , Young Adult
13.
Mol Nutr Food Res ; 64(7): e1900599, 2020 04.
Article in English | MEDLINE | ID: mdl-31917888

ABSTRACT

SCOPE: High-fat diet (HFD)-induced obesity impairs macrophage-to-feces reverse cholesterol transport (RCT). It is hypothesized that dietary supplementation with the polyunsaturated fatty acids conjugated linoleic acid (CLA) or alpha linolenic acid (ALA) would prevent HFD-impaired RCT by modulating hepatic protein pathways. METHODS AND RESULTS: ApoE3L.CETP mice are fed a HFD supplemented ± CLA or ALA for 12 weeks and in vivo macrophage-to-feces RCT is determined. Hepatic cholesterol transporters and the hepatic proteome are assessed by immunoblotting and mass spectrometry, respectively. Mice fed HFD alone, but not ALA-HFD or CLA-HFD, exhibit increased systemic cholesterol levels, increased 3 H-cholesterol levels in plasma and liver but not feces during RCT, and reduced hepatic ABCG5/8 expression relative to LFD. ALA-HFD significantly reduces liver weight, hepatic cholesterol levels, and expression of the cholesterol synthesis enzyme farnesyl pyrophosphate synthase relative to HFD. ALA further increases the expression of acetyl-coA oxidase-associated proteins and suppress PPARα-induced proteins relative to HFD. CLA does not significantly attenuate hepatic lipid levels but is associated with reduced hepatic expression of fatty acid binding protein (FABP)-1/FABP4 levels relative to HFD, and reduced inflammatory pathway activation relative to ALA-HFD. CONCLUSION: ALA and CLA exert distinct mechanistic advantages on cholesterol homeostasis and RCT in obesity.


Subject(s)
Cholesterol/metabolism , Linoleic Acids, Conjugated/pharmacology , Liver/drug effects , Obesity/diet therapy , alpha-Linolenic Acid/pharmacology , ATP Binding Cassette Transporter, Subfamily G, Member 5/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 8/metabolism , Animals , Apolipoprotein E3/genetics , Diet, High-Fat/adverse effects , Dietary Supplements , Feces , Lipoproteins/metabolism , Liver/metabolism , Macrophages/drug effects , Macrophages/metabolism , Male , Mice, Transgenic , Obesity/metabolism , Sterol Regulatory Element Binding Protein 2/metabolism
14.
Public Health Nutr ; 23(13): 2373-2383, 2020 09.
Article in English | MEDLINE | ID: mdl-31829294

ABSTRACT

OBJECTIVE: To apply a dietary modelling approach to investigate the impact of substituting beef intakes with three types of alternative fatty acid (FA) composition of beef on population dietary fat intakes. DESIGN: Cross-sectional, national food consumption survey - the National Adult Nutrition Survey (NANS). The fat content of the beef-containing food codes (n 52) and recipes (n 99) were updated with FA composition data from beef from animals receiving one of three ruminant dietary interventions: grass-fed (GRASS), grass finished on grass silage and concentrates (GSC) or concentrate-fed (CONC). Mean daily fat intakes, adherence to dietary guidelines and the impact of altering beef FA composition on dietary fat sources were characterised. SETTING: Ireland. PARTICIPANTS: Beef consumers (n 1044) aged 18-90 years. RESULTS: Grass-based feeding practices improved dietary intakes of a number of individual FA, wherein myristic acid (C14 : 0) and palmitic acid (C16 : 0) were decreased, with an increase in conjugated linoleic acid (C18 : 2c9,t11) and trans-vaccenic acid (C18 : 1t11; P < 0·05). Improved adherence with dietary recommendations for total fat (98·5 %), SFA (57·4 %) and PUFA (98·8 %) was observed in the grass-fed beef scenario (P < 0·001). Trans-fat intakes were increased significantly in the grass-fed beef scenario (P < 0·001). CONCLUSIONS: To the best of our knowledge, the present study is the first to characterise the impact of grass-fed beef consumption at population level. The study suggests that habitual consumption of grass-fed beef may have potential as a public health strategy to improve dietary fat quality.


Subject(s)
Dietary Fats/administration & dosage , Fatty Acids/analysis , Red Meat/analysis , Adolescent , Adult , Aged , Aged, 80 and over , Animal Feed , Animals , Cattle , Cross-Sectional Studies , Diet , Humans , Ireland , Middle Aged , Young Adult
15.
J Sci Food Agric ; 100(1): 245-257, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31512244

ABSTRACT

BACKGROUND: This study was conducted to assess whether there are differences in consumer liking of beef. Samples were collected from different groups and analyses were conducted, including quantitative descriptive analysis, consumer panels and instrumental analyses. Palatability traits, such as aroma liking, tenderness, juiciness, flavour liking and overall liking (OL), were rated by consumers. RESULTS: Warner-Bratzler shear force was negatively associated with tender mouthfeel and consumer tenderness score. Cluster analysis identified four groups of clusters, which were described as 'easily pleased', 'bull beef liker', 'tender beef liker' and 'fastidious' consumers. Cluster group 2 awarded a higher score for bulls and located in a separate region on the external preference map. CONCLUSION: External preference mapping showed the association between consumer liking of beef and sensory attributes. © 2019 Society of Chemical Industry.


Subject(s)
Consumer Behavior , Meat/analysis , Animals , Cattle , Cluster Analysis , Female , Flavoring Agents/analysis , Food Preferences , Humans , Male , Taste
16.
Foods ; 8(7)2019 Jul 18.
Article in English | MEDLINE | ID: mdl-31323755

ABSTRACT

The objective was to compare the quality of beef from bulls reared in typical Irish indoor systems or in novel grass-based systems. Bulls were assigned to one of the following systems: (a) grass silage plus barley-based concentrate ad libitum (CON); (b) grass silage ad libitum plus 5 kg of concentrate (SC); (c) grazed grass without supplementation (G0); (d) grazed grass plus 0.5 kg of the dietary dry matter intake as concentrate (GC) for (100 days) until slaughter (14.99 months). Carcass characteristics and pH decline were recorded. Longissimus thoracis was collected for analytical and sensory analysis. Lower carcass weight, conformation and fatness scores were found for grazing compared to CON and SC groups. CON bulls had highest intramuscular fat and lighter meat colour compared with grazing bulls. The SC meat (14 days aged) was rated higher for tenderness, texture, flavour and acceptability compared with grazing groups. CON saturated and monounsaturated fatty acid (FA) concentration was highest, conversely, omega-3 FA concentration was higher for GC compared with CON, while no differences were found in polyunsaturated FA. In conclusion, while market fatness specification was not reached by grazed grass treatments, beef eating quality was not detrimentally affected and nutritional quality was improved.

17.
Foods ; 8(7)2019 Jul 23.
Article in English | MEDLINE | ID: mdl-31340599

ABSTRACT

The biochemical and organoleptic characteristics of the longissimus thoracis muscle from suckler bulls (n = 56) finished on a concentrate-based system (C) or raised in a pasture-based system (P) incorporating 99 (P99), 162 (P162) or 231 days (P231) of grazing prior to indoor finishing on the concentrate-based diet were investigated. Age at slaughter increased with increasing period at pasture. Intramuscular fat concentration was lower (p < 0.001) for P99 than for C, P162 and P231 bulls, which did not differ. Soluble collagen proportion was lower (p < 0.01) for P162 and P231 than for P99 and C bulls. Collagen cross-link content was higher (p < 0.05) for P231 than for P99 and C bulls and for P162 than for C bulls. The proportion of type I muscle fibres was higher (p < 0.01) for P231 and P162 than for P99 and C bulls. Sensory tenderness was higher (p < 0.001) for C and P162 than for P99 and P231 bulls and overall liking was higher (p < 0.01) for C than for P99 and P231 bulls but similar to P162 bulls. Extending the grazing period to 162 days did not negatively influence the sensory qualities of beef compared to the intensive concentrate-based system.

18.
Food Res Int ; 115: 54-64, 2019 01.
Article in English | MEDLINE | ID: mdl-30599976

ABSTRACT

Animal production factors can affect the sensory quality of lamb meat. The study investigated the effect of diet composition and duration of consumption on the proximate analysis, volatile profile and sensory quality of lamb meat. Ninety-nine male Texel × Scottish Blackface lambs were raised at pasture for 10 months before being assigned in groups of 11 to one of the following treatments: 100% Silage (S) for 36 (S36), 54 (S54) or 72 (S72) days; 50% Silage - 50% Concentrate (SC) for 36 (SC36), 54 (SC54) or 72 (SC72) days; 100% Concentrate (C) for 36 (C36) or 54 (C54) or 72 (C72) days. A trained sensory panel found Intensity of Lamb Aroma, Dry Aftertaste and Astringent Aftertaste to be higher in meat from lambs on the concentrate diet. Discriminant analysis showed that the volatile profile enabled discrimination of lamb based on dietary treatment but the volatile differences were insufficient to impact highly on sensory quality. Muscle from animals in the S54 group had higher Manure/Faecal Aroma and Woolly Aroma than the SC54 and C54 groups, possibly related to higher levels of indole and skatole. Further research is required to establish if these small differences would influence consumer acceptability.


Subject(s)
Animal Feed/analysis , Diet/veterinary , Red Meat/analysis , Volatile Organic Compounds/analysis , Animals , Consumer Behavior , Discriminant Analysis , Food Quality , Humans , Male , Sheep, Domestic , Silage/analysis , Skatole/analysis , Taste
19.
J Food Sci ; 83(10): 2466-2477, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30251256

ABSTRACT

The aim of this study was to assess the effect of castration and slaughter age on the volatile profile of cooked meat from Scottish Blackface (SB) and Texel × Scottish Blackface (T × SB) lambs. M. longissimus thoracis et lumborum was sampled at slaughter and subjected to volatile analysis by SPME-GC-MS. Rams had higher relative proportions, expressed as relative abundance (RA), in lipid oxidation products while castrates had higher RA in pyrazines and benzenoid compounds. There was no consistent age effect on the RA of volatiles, although rams in November and January had a different volatile profile to castrates. There were higher proportions of free branched-chain fatty acids in muscle from SB compared to T × SB lambs. Overall, the results showed that production factors affected the volatile profile of cooked lamb meat which may explain differences in lamb flavor. PRACTICAL APPLICATION: Lamb meat has a characteristic flavor which, according to the evidence to date, may be influenced by farm production factors like gender or slaughter age. Our results showed variations in the proportions of some flavor compounds in cooked lamb between rams and castrated lambs while an increase in slaughter age did not have a consistent effect on proportions of compounds.


Subject(s)
Meat/analysis , Muscles/chemistry , Volatile Organic Compounds/chemistry , Abattoirs , Age Factors , Animals , Breeding , Cooking , Fatty Acids/chemistry , Fatty Acids/metabolism , Flavoring Agents/chemistry , Flavoring Agents/metabolism , Gas Chromatography-Mass Spectrometry , Male , Muscles/metabolism , Orchiectomy , Pyrazines/analysis , Pyrazines/metabolism , Sheep/genetics , Sheep/metabolism , Sheep/surgery , Sheep, Domestic/genetics , Sheep, Domestic/metabolism , Sheep, Domestic/surgery , Taste , Volatile Organic Compounds/metabolism
20.
Meat Sci ; 144: 2-14, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29859716

ABSTRACT

The authenticity of meat is now an important consideration in the multi-step food chain from production of animals on farm to consumer consumption of the final meat product. A range of techniques, involving analysis of elemental and molecular constituents of meat, fingerprint profiling and multivariate statistical analysis exists and these techniques are evolving in the quest to provide robust methods of establishing the dietary background of animals and the geographical origin of the meat derived from them. The potential application to meat authentication of techniques such as stable isotope ratio analysis applied to different animal tissues, measurement in meat of compounds directly derived from the diet of animals, such as fatty acids and fat soluble vitamins, and spectroscopy is explored. Challenges pertaining to the interpretation of data, as they relate to assignment of dietary background or geographical origin, are discussed.


Subject(s)
Diet/veterinary , Food Analysis/methods , Meat/standards , Animals
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