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Summary This study investigated the effects of skin‐on and skin‐off processing methods on processing efficiency, product yield and meat quality of goat carcasses. A total of twenty‐seven goats (nine/treatment, 6 months old) were processed using three methods: (1) skin‐on for ethnic consumers, (2) skin‐off for traditional consumers and (3) skin‐off‐late (skin removal after chilling) for primarily traditional consumers, with an option for ethnic consumers with skin‐on. Processing times (slaughter, chilling, fabrication) and yields (chilling and fabrication) were compared. Meat quality and appearance were evaluated using sarcomere length, Warner‐Brazler shear force, collagen content and muscle colour. Skin‐on carcasses required significantly longer chilling times to reach the internal body temperature at ≤4.4 °C (9.5 h) compared to skin‐off carcasses (7 h), presumably due to the presence of the skin. Despite this, the total processing time from stunning to fabrication showed no significant difference across treatments, although the skin‐off‐late carcasses had longer fabrication times due to the skin removal step (P < 0.05). Dressing yield was lower in the skin‐off group, and fabrication yield was reduced in the skin‐off‐late carcasses (P < 0.05). Skin‐on and skin‐off‐late carcasses showed longer sarcomere lengths and lower Warner Bratzler shear forces than skin‐off carcasses (P < 0.05). Additionally, the skin‐on group had higher collagen content than the skin‐off group. Muscle L* values were higher in skin‐on and skin‐off‐late carcasses (P < 0.05), with no significant differences in a* and b* values across treatments. This research highlights the potential benefits of the skin‐off‐late method for goat farmers, processors and consumers, offering improved dressing yield, meat tenderness and visual appearance. The skin‐off‐late method also provides an alternative processing option that could satisfy both traditional and ethnic consumer preferences. [ABSTRACT FROM AUTHOR]

ABSTRACT: Transportation of end-of-cycle hens (EOCH) may result in birds’ experiencing metabolic stress, which changes muscle characteristics. This study evaluated the impacts of simulated transport on muscle characteristics of white-feathered EOCH (65–70 wk). The factorial arrangement included treatments of T/RH (-10°C uncontrolled RH [-10], 21°C with 30 [21/30] or 80% RH [21/80], 30°C with 30 [30/30] or 80% RH [30/80]), duration (4, 8, 12 h), and feather cover (105 well-feathered [WF], 105 poorly-feathered [PF]). A total of 210 hens/replicate/farm (farm=block; 3 total) were tested during the simulated transport. Crates (one/duration/replicate), divided in half for each feather cover (seven hens/side), were placed in a climate-controlled chamber. Prior to exposure, hens were fasted (6 h). BW was taken pre- and post-exposure, and the difference was calculated as live shrink. Post-exposure to the test conditions, birds were slaughtered and carcasses were analyzed for muscle characteristics. Data were analyzed as a randomized complete block design (farm of origin as block) with ANOVA (Proc Mixed, SAS 9.4; significance declared at P ≤ 0.05). Duration resulted in more weight loss for the birds (P < 0.01). Final pH measures (30 h post-mortem) were higher in hens exposed to -10 than 21/80, 30/30, and 30/80 and this difference was exacerbated with time (breast P < 0.01 and thigh P = 0.01). For muscle color, breast and thigh (both feather covers; P = 0.01) were darker in the -10 treatment while redness values were higher in EOCH exposed to this treatment (breast and thigh P < 0.01). Additionally, thigh muscle redness was higher in PF hens (P < 0.01). Thaw and cooking losses were impacted by T/RH and duration (thaw loss P = 0.03 and cook loss P = 0.04). Cook loss was also influenced by T/RH and feather cover with PF hen muscles losing less water during cooking in the -10 treatment (P = 0.01). Overall, the largest impact from transport was found in hens exposed for a longer duration to -10 antemortem compared to other treatments, demonstrating a significant impact on muscle characteristics from ante-mortem stress.

In the present work, the effect of high pressure processing (HPP) (0, 100, 200 and 300 MPa) and different treatment time (5 and 10 minutes) on the moisture uptake, cooking yield, colour and texture, as well as microbial population of chicken breast fillets was investigated. The application of high hydrostatic pressure resulted in a modification of quality parameters of chicken breast meat. By increasing pressure and time of the treatment the moisture uptake was reduced: samples treated with 300 MPa for 10 min had the lowest moisture uptake values. Cooking yield was not affected by HPP treatments. Increased pressure affected the colour by increasing L*, a* and b* values (only HPP treatment of 100 MPa in duration of 5 and 10 minutes did not affect colour of chicken breast meat). Lower pressures (100 and 200 MPa) tenderized, whereas elevated pressure (300 MPa) increased hardness in chicken breast fillets. Higher level of pressure (300 MPa) reduced bacteria count by about 3.0 - 5.3 log (CFU/g), depending on the microorganism and duration of the process. [ABSTRACT FROM AUTHOR]

1. The effects of age and sex on body weight, carcass traits, physical and chemical properties of breast muscle from chickens and helmeted guinea fowls managed under village free-range conditions were assessed in random samples of 48 guinea fowls and 48 chickens obtained from local markets. 2. Guinea fowls had higher body weight, hot carcass weight, cold dressed weight and breast weight than chickens. 3. Guinea fowls had more dry matter, protein and less fat than chickens. Ash content did not differ between guinea fowls and chickens. Protein and fat increased, whereas dry matter and ash decreased with age (P < 0.05) 4. Chicken meat was lighter, less red and more yellow than guinea fowl meat. Cooking loss was higher in guinea fowls, male and grower birds than chickens, females and adult birds, respectively. Shear force was affected by age, as mature birds had a higher value than growers. 5. Guinea fowl carcasses contained more meat that was leaner, higher in protein and redder compared with chicken meat. As age increased the meat increased in protein and fat content and shear force, whereas colour became darker, redder and yellower. [ABSTRACT FROM AUTHOR]

Abstract: The effect of type of silage offered to beef heifers during the finishing period on aspects of beef quality was determined. In two experiments, a diet based on grass silage (GS) was compared with a diet based on maize silage (MS) or whole-crop wheat silage (WCW). Compared to the GS-based diet, increasing the amount of MS linearly increased fat whiteness while the increase in fat whiteness due to WCW was dependent on the stage of crop maturity at harvesting. There was no effect of diet on muscle colour or on muscle pH measured at 48h post-mortem, drip loss, taste panel traits after 14days ageing or shear force values at 2, 7 or 14days ageing. The alternative silages decreased the n−3 polyunsaturated fatty acid proportion and increased the linoleic:linolenic acid ratio in intramuscular lipid. It is concluded that type of silage affects fat colour and fatty acid composition of muscle but not the other muscle characteristics examined. [Copyright &y& Elsevier]

Abstract: The effect of the diet offered to heifer progeny of a grassland-based spring calving suckler beef production system during the finishing period on the colour of carcass fat and the colour and sensory characteristics of longissimus thoracis et lumborum muscle was determined in the context of suitability for one sector of the Italian beef market. A diet based on grass silage plus concentrate was compared with a diet based on concentrates and wheat straw. Compared to animals offered the concentrate-based diet both the kidney/channel fat and subcutaneous fat from animals offered the grass silage based diet was more yellow and a greater proportion (33 v 0%) were deemed unacceptable for this market on the basis of fat colour. There was no effect of diet on muscle colour or on muscle pH, drip loss, taste panel traits or shear force values or on market acceptability based on muscle colour. The maximum level of dietary inclusion of grass silage to avoid inadequate fat colour remains to be determined. [Copyright &y& Elsevier]

Abstract: Groups of 8 lambs were allocated to one of five concentrate diets supplemented with all-rac-α-tocopheryl acetate containing 30 (C30), 60 (C60), 120 (C120), 250 (C250) and 500 (C500) mg/kg dry matter. Two other groups were fed grass silage and 400g/day concentrate with 60 (S60) or 500 (S500) mg α-tocopheryl acetate/kg dry matter. Within diet, vitamin E level did not affect growth performance or carcass characteristics. Basal diet did not affect final live weight, conformation and fatness scores. M. semimembranosus from S lambs contained more α-tocopherol than that of C lambs on the same intake and by day 6 in MAP (75%O2/25%CO2) chroma and a* were below acceptable levels in C30 lambs. TBARS were higher in C30 and C60 muscle than in other treatments (P<0.001) after 3 and 6days display. Muscle fatty acid composition varied with basal diet but lipid oxidation depended more on vitamin E concentration with an initial concentration of 1.9μg/g muscle preventing significant lipid oxidation. [Copyright &y& Elsevier]

Abstract: To examine the effect of a modification of a typically Irish dairy calf-to-beef production system, Charolais×Friesian steers were offered a finishing ration of grass silage ad libitum and 5.6kg concentrates daily for 174days prior to slaughter at 25months of age or grass silage ad libitum for 174days, followed by pasture for 167days and slaughter at 30months of age. Finishing at pasture increased carcass weight (376 vs. 342kg) but did not affect intra-muscular lipid concentration (28 vs. 24g/kg). Finishing at pasture decreased Longissimus thoracis et lumborum lightness (35.6 vs. 36.9) and increased shear force of muscle at 2 (8.54 vs 4.32) and 7days (5.21 vs 3.64kg) post-mortem but not at 14days post-mortem (4.45 vs. 3.42kg). Finishing at pasture did not affect the sensory characteristics of tenderness, juiciness, firmness or chewiness and tended (P<0.1) to decrease texture and acceptability. It is concluded that modification of this beef production system as described, had minor effects on beef quality which are unlikely to be of commercial significance. [Copyright &y& Elsevier]

Rainbow trout with an average initial weight of 160 g were fed during 42 days diets containing varied keto-carotenoids astaxanthin (Ax)/canthaxanthin (Cx) ratio, as follows: Ax 100% : Cx 0%; Ax 75% : Cx 25%; Ax 50% : Cx 50%; Ax 25% : Cx 75% and Ax 0% : Cx 100%. Muscle colour and carotenoid muscle retention were studied. Colour parameter values for mixed astaxanthin–canthaxanthin-fed fish were intermediate between those obtained for Ax 0% : Cx 100% fed fish group and for Ax 100% : Cx 0% fed fish group. Concerning muscle carotenoid retention, it has been observed that as the level of canthaxanthin in diet increased, the muscle total carotenoid retention decreased. In the mean time, as the level of canthaxanthin in diet increased, the muscle astaxanthin retention decreased while that of canthaxanthin increased. The results reported here provide further evidence of non-beneficial effects in terms of muscle colour and muscle carotenoid retention of the use of varying dietary astaxanthin/canthaxanthin ratio for feeding rainbow trout compared to values obtained for astaxanthin-only feed. [ABSTRACT FROM AUTHOR]

Abstract: Rainbow trout were pigmented with diets containing astaxanthin or canthaxanthin for 100days, and then they were moist or dry heat-cooked. Fish fillet weight, fillet colour, and fillet biochemical contents (moisture, canthaxanthin and astaxanthin contents, and total lipid content) were analyzed. There was no significant effect of using astaxanthin or canthaxanthin on moisture, lipid or carotenoid contents of fish fillet. Giving astaxanthin or canthaxanthin to fish resulted in different hues; astaxanthin-fed fish yielded fillets that were visually more red than those of canthaxanthin-fed fish. The dry heat-cooking procedure showed the highest impact on the fillet colour. Carotenoid retention was affected by carotenoid source and cooking procedure. Canthaxanthin appeared more stable after heat processing than did astaxanthin. [Copyright &y& Elsevier]

Holstein-Friesian (HF), Piedmontese × Holstein-Friesian (PM) and Romagnola × Holstein-Friesian (RO) steers were compared for muscle composition and colour. A total of 120 steers in a 3 breed types (HF, PM and RO) × 2 feeding levels (low and high) × 2 finishing periods (short, S and extended, E) factorial experiment were used. Three samples of m. longissimus were taken for chemical analysis, measurement of drip loss and Hunterlab colour measurements. Muscle moisture and protein concentrations were lower, and lipid concentration was higher for HF than for PM and RO, which were similar. There were no effects of feeding level on chemical composition, but after blooming all colour values except hue were lower for the higher feeding level. The E finishing period reduced moisture, protein, drip-loss, L (lightness), a (redness) and chroma values. It is concluded that PM and RO had similar muscle composition but HF had a higher lipid concentration. Feeding level had few effects on muscle composition, but extended finishing increased all measures of fatness and reduced colour values. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to determine the effects of the use of astaxanthin alternate feeding on rainbow trout pigmentation in term of astaxanthin serum concentration, muscle colour and astaxanthin muscle retention. Four hundred and fifty rainbow trout were fed the same basal diet supplemented with two different astaxanthin levels, 100, and 200 mg astaxanthin kg−1 of diet, hereafter designated as AX100 and AX200, respectively. An additional astaxanthin-free (AX0) diet was used. The experimental treatments were as follows: (1) REF=AX100 diet at each meal each day, served as reference; (2) SD1=AX100 diet at each meal the first day followed by AX0 diet at each meal every second day; (3) SD2=AX100 diet and AX0 diet in alternate meals each day; (4) R2=AX200 diet and AX0 diet in alternate meals each day; (5) R4=AX200 diet at the first meal the first day followed by AX0 diet at the second meal the first day and at each meal every second day. Fish were fed the experimental feeding schedule for 42 days. At the end of the experiment there were no significant differences among fish fed the different feeding schedules in term of final mean weight, specific growth rate and feed efficiency ratio. SD2 fish group displayed the highest (P <0.05) astaxanthin serum concentration and the R4 fish group the lowest one. REF and R2 fish groups showed similar astaxanthin serum concentrations. Muscle chroma showed the most pronounced effect. It increased significantly for all fish groups during the experiment. At the end of the experiment REF and R2 fish groups displayed higher values than SD1 and R4 fish groups. Muscle astaxanthin concentrations increased significantly during the experiment whatever the astaxanthin feeding schedule. At the end of the experiment, the highest muscle astaxanthin concentration was recorded for R2 fish group while the lowest was noted for R4 fish group. Except for SD1 and R4 fish groups, muscle astaxanthin retention decreased significantly during the experiment. At the end of the experiment, muscle astaxanthin retention coefficients for SD2 fish group were significantly higher than those for REF fish group. The results reported here provide further evidence of the potential applicability of alternate astaxanthin feeding on rainbow trout pigmentation. Extending the optimisation of the SD2 treatment will therefore be subject for future studies. Its application could result in cost saving in the fish farming industry. [Copyright &y& Elsevier]

Abstract: Steers were offered grass silage ad libitum and 6.4 kg concentrates daily for 126 days or silage ad libitum for 35 days, followed by concentrates ad libitum (Experiment 1). Steers were offered grass silage ad libitum and 6 kg concentrates daily for 154 days, concentrates ad libitum or grass silage ad libitum for 112 days followed by concentrates ad libitum (Experiment 2). All treatments received the same total concentrate allowance. In Experiment 1, there was no difference in any measurement of meat quality. In Experiment 2, ad libitum concentrate feeding per se, decreased redness and increased shear force of muscle at 2 days post-mortem. Delaying concentrate feeding decreased fat yellowness, decreased shear force at 7 and 14 days post-mortem and increased muscle redness at 14 days post-mortem. Modifications of the beef production system examined had minor effects on beef quality which are unlikely to be of commercial significance. [Copyright &y& Elsevier]

Abstract: A quantitative genetic analysis was performed to assess the suitability of automated image analysis of cutlets as a selection tool to genetically improve flesh composition and colour in large rainbow trout. Fish were reared on two diets with different lipid and protein content to assess the robustness of the image analysis method across different nutritional environments, and the strength of potential genotype-by-diet interactions. Chops were scanned and digitally analysed for colour (chroma, hue, and lightness) and for areas of lipid stripes, dorsal lipid, red muscle and white muscle. Percents of lipid and white muscle area to whole chop area were compared to percent chop lipid and protein recorded by chemical analysis. The results showed that on both diets, percent chop lipid and percent white muscle area displayed high phenotypic (≥0.42) and genetic correlations (≥0.70) with the respective chemical lipid and protein percents. Moreover, on both diets, the lipid area percents had moderate to high heritabilities (h 2 =0.29–0.70) that were of the same magnitude or higher compared to the previously published estimates for chemically analysed lipid traits. These results confirm that regardless of the diet composition, true lipid and protein deposition can be genetically improved by selecting for the respective image analysis traits. Muscle lightness, hue (tint of colour) and chroma (saturation level of colour) displayed moderate to high heritabilities (h 2 =0.32–0.46), and phenotypic and genetic correlations between these traits were favourable. Muscle colour can thus be effectively improved by selection. Some genetic constraints for breeding efforts were identified, in terms of lipid deposited at different locations within the body correlating only weakly. Genetic correlations between diets were strongly positive (≥0.85), revealing only weak re-ranking of families across the diet treatments. [Copyright &y& Elsevier]

Transportation of end-of-cycle hens (EOCH) may result in birds' experiencing metabolic stress, which changes muscle characteristics. This study evaluated the impacts of simulated transport on muscle characteristics of white-feathered EOCH (65-70 wk). The factorial arrangement included treatments of T/RH (-10°C uncontrolled RH [-10], 21°C with 30 [21/30] or 80% RH [21/80], 30°C with 30 [30/30] or 80% RH [30/80]), duration (4, 8, 12 h), and feather cover (105 well-feathered [WF], 105 poorly-feathered [PF]). A total of 210 hens/replicate/farm (farm=block; 3 total) were tested during the simulated transport. Crates (one/duration/replicate), divided in half for each feather cover (seven hens/side), were placed in a climate-controlled chamber. Prior to exposure, hens were fasted (6 h). BW was taken pre- and post-exposure, and the difference was calculated as live shrink. Post-exposure to the test conditions, birds were slaughtered and carcasses were analyzed for muscle characteristics. Data were analyzed as a randomized complete block design (farm of origin as block) with ANOVA (Proc Mixed, SAS 9.4; significance declared at P ≤ 0.05). Duration resulted in more weight loss for the birds (P < 0.01). Final pH measures (30 h post-mortem) were higher in hens exposed to -10 than 21/80, 30/30, and 30/80 and this difference was exacerbated with time (breast P < 0.01 and thigh P = 0.01). For muscle color, breast and thigh (both feather covers; P = 0.01) were darker in the -10 treatment while redness values were higher in EOCH exposed to this treatment (breast and thigh P < 0.01). Additionally, thigh muscle redness was higher in PF hens (P < 0.01). Thaw and cooking losses were impacted by T/RH and duration (thaw loss P = 0.03 and cook loss P = 0.04). Cook loss was also influenced by T/RH and feather cover with PF hen muscles losing less water during cooking in the -10 treatment (P = 0.01). Overall, the largest impact from transport was found in hens exposed for a longer duration to -10 antemortem compared to other treatments, demonstrating a significant impact on muscle characteristics from ante-mortem stress., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)