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1.
Indoor-kept concentrate-fed light lambs (n = 54) were supplemented with 500 mg of dl-α-tocopheryl acetate/kg concentrate for 0, 10, 20 and 30 d before slaughtering at 22–24 kg BW. Simultaneously, 8 lambs with their dams were alfalfa-grazed and the lambs were slaughtered at the same weight. The age at slaughter and carcass characteristics were more affected by grazing than by supplementation with α-tocopherol. The grazing lambs had similar α-tocopherol levels to the lambs fed concentrate with dl-α-tocopheryl acetate for 10 days before slaughter. The length of the feeding period affected the evolution of the color, delaying the blooming and discoloration of the meat. Feeding lambs α-tocopherol enriched concentrate during the last 10 days of life or grazing them on alfalfa drastically diminished the lipid oxidation of the meat. Alfalfa grazing is a feasible alternative to increase light lamb meat shelf life without using additives.  相似文献   

2.
Ripoll G  Albertí P  Joy M 《Meat science》2012,90(2):457-464
One hundred and twenty-seven lambs were fed as follows: lambs and dams grazing alfalfa (Gr); the same as Gr but lambs had access to concentrate (Gr + S); ewes grazed and lambs received milk and concentrate until weaning and thereafter concentrate and straw (Rat-Gr); ewes and lambs were stall-fed (Ind). Lambs were slaughtered at 22-24 kg live weight and fat and M. rectus abdominis colour was measured instrumentally and subjectively. The evolution of the instrumental colour and texture of M. longissimus lumborum was also recorded.There were significant differences in the instrumental colour of subcutaneous fat amongst feeding systems, but no differences were observed upon visual appraisal. On average, M. rectus abdominis colour in the four feeding systems was classed as pink. Differences in longissimus thoracis colour at 0 h disappeared at 24 h of air exposure and there were no differences in pH or cooking losses. At no time were any differences in instrumental texture found.  相似文献   

3.
This study investigated changes in plasma carotenoid concentration and fat reflectance spectrum characteristics and color in lambs fed a carotenoid-rich diet with low-level (L, 100 g/lamb/day) or high-level (H, 400 g/lamb/day) of barley supplementation for 75 days before slaughter. Each treatment used 24 Romane male lambs that were individually penned indoors. Plasma carotenoid concentration at slaughter was 16% lower in H lambs than in L lambs. H lambs had heavier and fatter carcasses than L lambs. Yellowness and redness of perirenal fat were slightly lower in H lambs than in L lambs. The absolute value of the mean integral (AVMI) calculated from the reflectance spectrum of the fat in the 450–510 nm band was not affected by the treatment. Yellowness, chroma and AVMI of subcutaneous fat were not affected by the treatment but decreased with initial animal's liveweight.  相似文献   

4.
To investigate the influence of diet and aging on beef palatability, lipid oxidative stability, and fatty acid composition, crossbred steers were assigned to Feedlot S (alfalfa and grain), Forage TR (triticale and annual ryegrass), Forage TK (triticale and kale), or Forage + Feedlot (grazing ryegrass, fescue and orchardgrass, finished on alfalfa and grain) dietary treatments. Heifers were finished on Feedlot H (alfalfa and grain). Longissimus and tricep muscles were sampled from these animals for steaks and ground beef, respectively. Steaks were either dry- or wet-aged for 14 d. Ground beef was dry-aged, wet-aged for 14 d, or not aged. Trained sensory panelists evaluated palatability attributes of steaks and ground beef. Diet did not influence sensory attributes of steaks or ground beef. Aging impacted (P < 0.05) sensory attributes of ground beef. Diet and aging had no impact on lipid oxidative stability but affected fatty acid composition of raw ground beef.  相似文献   

5.
Effects of chop length (shorter: 6 mm, or longer: 19 mm) of alfalfa silage and oat silage were determined in 16 mid-lactation Holstein cows, 4 of which were rumen cannulated, using a replicated 4 × 4 Latin square design with a 2 × 2 arrangement of treatments. Experimental periods were 21 d long and consisted of 14 d of adaptation and 7 d of sampling. Cows received a total mixed ration containing [dry matter (DM) basis] 42.0% barley grain-based energy supplement, 10% protein supplement, and 24% of DM longer chop or shorter chop alfalfa silage and 24% of DM longer chop or shorter chop oat silage. Rumen pH was measured continuously, and rumen liquid flow rates were determined in rumen-cannulated cows. Feeding behavior was determined by videotaping, and meal patterns were determined by continuously weighing the feed in the bunk of 8 cows. Reducing the chop length of alfalfa silage and oat silage reduced the average geometric particle length from 14.2 to 10.9 mm and from 13.4 to 10.4 mm, respectively. Reducing the alfalfa chop length did not affect feed intake, whereas reducing the oat silage chop length increased DM intake from to 19.4 to 21.2 kg/d. Reducing the chop lengths of alfalfa silage and oat silage chop length did not affect milk production, rumen fermentation, feeding behavior, meal patterns, and blood metabolites. Daily milk yield, milk fat percentage, and milk protein percentage averaged 36.1 kg/d, 3.00%, and 3.16%, respectively, across diets. The low milk fat percentages suggest that the diets induced subacute ruminal acidosis. This was also substantiated by the rumen pH, which was below 5.6 for more than 122 min/d for all diets. The onset of subacute ruminal acidosis despite apparently adequate dietary neutral detergent fiber content and particle size distribution as well as the long duration of chewing might be attributed to sorting against long feed particles.  相似文献   

6.
Effects of chop length (shorter = 10 mm or longer = 19 mm) of alfalfa silage and corn silage were determined in 16 midlactation Holstein cows using a 4 × 4 Latin square design with a 2 × 2 arrangement of treatments. Experimental periods were 21 d long and consisted of 14 d of adaptation and 7 d of sampling. Cows received total mixed ration containing (dry matter basis) 44.0% barley grain-based energy supplement, 12.6% protein supplement, and 21.7% longer chop or shorter chop alfalfa silage and 21.7% longer chop or shorter chop corn silage. Reducing the chop length of alfalfa silage and corn silage reduced the average geometric particle length from 14.4 to 11.0 mm and from 14.2 to 10.4 mm, respectively. Reducing the chop length of both silages reduced the proportion of the diets retained by the 8-and 19-mm screen of the Penn State Particle Separator from 55.0 to 46.0% of dry matter. Reducing the alfalfa chop length increased total rumen volatile fatty acids at 4 to 5 h after feeding but did not affect rumen pH at 4 to 5 h after feeding, feed intake, and milk production. Reducing the corn silage chop length increased dry matter intake from 22.3 to 23.2 kg/d, increased rumen pH at 4 to 5 h after feeding from 6.12 to 6.20, but did not alter rumen volatile fatty acids at 4 to 5 h after feeding or milk production. Daily milk yield, milk fat percentage, and milk protein percentage averaged 38.2 kg/d, 2.62%, and 3.29%, respectively, across all diets. The low milk fat percentages suggest that all diets induced subacute ruminal acidosis (SARA), whereas the rumen pH did not indicate SARA. This discrepancy could be due to a difference in the time of rumen pH measurement and the time of the lowest rumen pH. Hence, the pH data need to be interpreted with caution. Diets could have induced SARA, because for all experimental diets the content of forage neutral detergent fiber was lower than recommended for barley grain-based diets.  相似文献   

7.
Condensed tannin in the form of a grape seed extract (GSE) was dosed to weaned wether lambs fed white clover (WC) or perennial ryegrass (PRG) over a 9‐week period to determine whether the ‘pastoral’ flavour and odour of meat could be altered. The concentrations of the pastoral flavour compounds indole and skatole were determined in the rumen fluid, blood plasma and intermuscular fat. The odour and flavour of fat and meat from the slaughtered lambs was assessed by a trained panel. The rumen fluid and blood plasma concentrations of indole and skatole were higher in those lambs fed WC compared to PRG (P < 0.05) and the overall meat flavour intensity was greater when feeding WC (P < 0.01). The observed concentration of indole and skatole in the fat between WC and PRG feeding treatments was not statistically different. Power analysis indicated that increasing the number of lambs per treatment group from 20 to 65 would result in a higher fat skatole concentration (P < 0.05) being detected in lambs fed WC compared to PRG. Dosing with GSE gave a small reduction in skatole concentration in the rumen fluid and reduced plasma concentration of indole and skatole (P < 0.001). Odour and flavour scores of the fat and meat samples were not particularly high however, dosing with GSE lowered the overall and sweet odour and the sheepy, camphor, faecal and barnyard flavour (P < 0.05). Although the plasma concentration of indole and skatole suggests that GSE reduced indole and skatole formation, the intermittent supply of the GSE to the rumen environment was not sufficient to reduce their concentration in the fat. Hence, the small difference in the scores for pastoral odour and flavour attributes associated with GSE treatment may arise from other unknown factors. From a primary investigation, there was no difference in the concentration of indole and skatole in fat samples collected from carcasses before and after chilling. Further investigations into meat pastoral flavour are warranted through feeding condensed tannin‐containing forages. Copyright © 2007 Society of Chemical Industry  相似文献   

8.
Rapeseed and sunflower oil were used to replace pork backfat in UK-style sausages by incorporating the oils as pre-formed emulsions. Replacing the pork backfat emulsion with rapeseed emulsion at total fat content of about 12%, reduced total saturated fatty acid (SFA) composition from 38% to 14% (4.5 to 1.8 g/100 g), increased monounsaturated fatty acid (MUFA) composition from 45% to 59% and increased polyunsaturated fatty acid (PUFA) composition from 15% to 25%. Partial replacement of pork backfat with rapeseed at a fat content of about 20% reduced SFA from 38% to 24% (7.2 to 4.8 g/100 g). There were no significant differences in eating quality and overall liking other than slight differences in the attributes ‘firmness’ and ‘particle size’. Improvement in the fatty acid composition was achieved without adversely affecting colour shelf life or lipid oxidation. The study suggests that a substantial reduction in SFA can be achieved by incorporating ‘healthy’ oils in UK-style sausages without adversely affecting eating quality or shelf life.  相似文献   

9.
Cookies prepared with white or wholegrain wheat flours and substituted with high-oleic sunflower seed (10 g/100 g and 30 g/100 g supplementation levels) and hull-less barley flour (30 g/100 g and 50 g/100 g levels) were evaluated for nutritional properties, physical and sensory attributes. Sunflower seed significantly increased the contents of Se, Zn, Mg, and Ca, as well as the contents of α-tocopherol and fat in cookies. The contents of Se, Cu, Fe, Zn and β-glucan were raised in cookies by barley supplementation. It was estimated that 100 g of barley and sunflower seed-supplemented cookies can meet about 18–49% of dietary reference intake (DRI) for Se. Both supplemented cookies were found not to pose a significant risk, with regard to excessive intakes of heavy elements (Pb, Cd, As, Hg). In addition, the supplementation with sunflower seed improved sensory properties of the cookies.  相似文献   

10.
11.
The major boar taint compounds androstenone and skatole as well as the minor compounds indole, 3α-androstenol and 3β-androstenol were determined in back fat samples of 23 male wild boars by applying a recently published SIDA–HS-SPME–GC/MS method. The boar pheromones androstenone, 3α-androstenol and 3β-androstenol were found in extraordinary high concentrations, resulting in mean values of 3329 ng/g androstenone, 1273 ng/g 3α-androstenol and 545 ng/g 3β-androstenol. Interestingly, skatole was not detectable in about 50% of the boars and negligibly low in all other samples as expressed by a mean skatole value of only 14 ng/g. Indole was also found in every sample, but again in low concentrations with a mean value of 40 ng/g. Possible factors explaining this remarkably low skatole deposition in wild boars such as intestinal flora and anatomy, dietary composition, housing or genetic predisposition are discussed in this paper.  相似文献   

12.
Twenty-nine crossbred boars were used to evaluate the effects of live weight and processing on the sensory attributes and concentrations of androstenedione and androstenone (boar taint) in boar meat. Boars were stratified by litter across six weight group endpoints (90.9, 95.5, 100.0, 104.5, 109.1, and 113.6 kg). Back fat and longissimus muscle from the lumbar region were used for androstenone determination, proximate analysis and sensory evaluation. Hams were cured for sensory analysis and were used to determine androstenone concentrations. Androstenone as an off-flavor did not differ (P > 0.05) among treatments for longissimus lean or cured hams and was found to be in the “threshold” to “none detected” range. Back fat androstenone concentration was positively correlated (P < 0.05) to hot carcass weight, however, lean androstenone concentration was not (P > 0.05). No relationship was found (P > 0.05) between androstenone concentration and days on feed, average daily gain or androstenedione concentration. Additionally, further processing decreased androstenone concentration by approximately 29%.  相似文献   

13.
The aim of this study was to assess the level of some phytochemicals in 19 raspberry cultivars grown in Lithuania. The content of total ellagic acid measured after 20 h acidic hydrolysis of investigated raspberry cultivars, varied from 119.8 (cv. ‘Pokusa’) to 323.5 mg/100 g (cv. ‘Bristol’). The content of total phenolics ranged from 278.6 (cv. ‘Pokusa’) to 714.7 mg/100 g (cv. ‘Bristol’). The total anthocyanins content varied from 2.1 (yellow cv. ‘Beglianka’) to 325.5 mg/100 g (black cv. ‘Bristol’). The radical scavenging capacity of the tested raspberry cultivars highly correlating with their total phenolics and total ellagic acid content (r = 0.90 and 0.92, respectively). The results of this study expand the knowledge about variation in the content of valuable bioactive compounds in raspberries and may help for the selection and validation of the most productive cultivars.  相似文献   

14.
Boar taint is a sensory defect mainly due to androstenone and skatole. The most common method to control boar taint is surgical castration at an early age. Vaccination against gonadotropin releasing factor (also known as immunocastration) is an alternative to surgical castration to reduce androstenone content. In this experiment, loins from 24 female (FE), 24 entire male (EM), 24 vaccinated males (IM) and 23 surgically castrated males (CM) were evaluated by eight trained panellists in 24 sessions. Loins were cooked in an oven at 180 °C for 10 min. Furthermore loins were evaluated by consumers and its androstenone and skatole content were also chemically determined. Meat from EM had higher androstenone and skatole odour and flavour than meat from FE, IM and CM and lower sweetness odour scores. High correlations were found between androstenone and skatole levels assessed by trained panelists, chemical analysis and consumers’ acceptability. Moreover meat from EM is mainly related to androstenone and skatole attributes.  相似文献   

15.
The effects of supplementation with grass silage and replacement of some corn in the concentrate with soybean meal (SBM) on milk production, and milk fatty acid (FA) profiles were evaluated in a replicated 4 × 4 Latin square study using 16 dairy cows grazing pasture composed of ryegrass, Kentucky bluegrass, and white clover. Each experimental period lasted for 3 wk. The 4 dietary treatments were PC, 20 h of access to grazing pasture, supplemented with 6 kg/d of corn-based concentrate mixture (96% corn; C); PCSB, 20 h of access to grazing pasture, supplemented with 6 kg/d of corn- and SBM-based concentrate mixture (78% corn and 18% SBM; CSB); SC, 7 h of access to grazing pasture during the day and 13 h of ad libitum access to grass silage at night, supplemented with 6 kg/d of C concentrate; and SCSB, 7 h of access to grazing pasture during the day and 13 h of ad libitum access to grass silage at night, supplemented with 6 kg/d of CSB concentrate. The concentrate mixtures were offered twice each day in the milking parlor and were consumed completely. Grass silage supplementation reduced dietary crude protein and concentration of total sugars, and dietary SBM inclusion increased dietary crude protein concentration and decreased dietary starch concentration. Milk yield and energy-corrected milk were increased by SBM supplementation of cows with access to grass silage. Milk protein concentration was lower in cows offered grass silage, regardless of whether SBM was fed. Dietary SBM inclusion tended to increase milk fat concentration. Plasma urea N was reduced by silage feeding and increased by SBM supplementation. Supplementation with grass silage overnight could represent a useful strategy for periods of lower pasture availability. Dietary inclusion of SBM in solely grazing cows had no effects on milk production and composition, exacerbated the inefficient capture of dietary N, and increased diet cost. Grass silage supplementation affected milk FA profiles, increasing both the FA derived from de novo synthesis and those derived from rumen microbial biomass, and decreasing the sum of C18 FA (mostly derived from diet or from mobilization of adipose tissue reserves). Milk fat concentrations of conjugated linoleic acid cis-9, trans-11, vaccenic acid (18:1 trans-11), and linolenic acid (18:3n-3) were unaffected by grass silage supplementation, suggesting that partial replacement of pasture by unwilted grass silage does not compromise the dietary quality of milk fat for humans.  相似文献   

16.
Forty-eight lambs were fed as follows: GR, lambs and dams grazed perennial pasture; GR+S, the same as GR except that lambs had access to concentrate; DRL-GRE, lambs in drylot and dams in rationed grazing; DRL, lambs with dams were stall-fed. DRL-GRE and DRL lambs were weaned at 45 days of age. Lambs were slaughtered when they reached 22–24 kg of live weight. Plasma cortisol concentration was determined three times before slaughter. Subcutaneous fat and meat colour, and texture were analysed.  相似文献   

17.
This research evaluated effects of feedlot backgrounding on 40, 70 or 100% alfalfa hay diets (40hay, 70hay; 100hay, respectively) or pasture grazing (Pasture) before pasture finishing, on performance and beef characteristics of Angus heifers. Ninety six female calves were allocated to the four feeding strategies. Backgrounding took place during 114 days and subsequent pasture finishing over 132 days. Heifers of each strategy were slaughtered after 114 days (end of the feedlot period) and at end of the study when all remaining animals were finished on pasture. Effects of backgrounding were associated with rate of gain. Backgrounding strategies 40hay and Pasture resulted in the best performance. Beef attributes were similar. At the end of the feedlot period, 100hay was smaller and leaner, less tender and less juicy. At the end of the study, Pasture and 40hay heifers had on average the largest back fat thickness and intramuscular fat measurements. No treatment effects were detected for Warner-Bratzler shear force, muscle pH, muscle color and sensory panel attributes.  相似文献   

18.
This article reports a study of the concentrations of dietary fiber (DF) and antioxidant capacity in fruits (pulp and oil) of a new açaí (Euterpe oleraceae) cultivar—‘BRS-Pará’, with a view to determine the possibility of using it as a source of antioxidants in functional foods or dietary supplements. Results show that ‘BRS-Pará’ açaí fruits has a high content of DF (71% dry matter) and oil (20.82%) as well as a high antioxidant capacity in both defatted matter and oil. ‘BRS-Pará’ Açaí fruits can be considered as an excellent source of antioxidant dietary fiber. Antioxidant capacity of açaí ‘BRS-Pará’ oil by DPPH assay was higher (EC50 = 646.3 g/g DPPH) than extra virgin olive oil (EC50 = 2057.27 g/g DPPH). These features provide açaí ‘BRS-Pará’ fruits with considerable potential for nutritional and health applications.  相似文献   

19.
Experiments were carried out in vivo and in vitro with four isolates of Penicillium expansum (I 1, E 11, C 28 and I 12) to evaluate their aggressiveness, growth and patulin accumulation in both usual (pears and apples) and less common hosts (apricots, peaches, strawberries and kiwifruits) of the pathogen. The 75% of isolates showed the ability to cause blue mould in all tested hosts. In particular, C 28 and I 1 were the most and the least aggressive isolates, respectively (52.9 and 10.6% infection and 20.7 and 15.4 mm lesion diameters). ‘Candonga’ strawberries and ‘Pinkcot’ apricots showed the largest lesion diameters (29.8 and 25.3 mm), followed by ‘Conference’ pears, ‘Spring Crest’ peaches and ‘Abate Fetel’ pears. With the exception of ‘Candonga’ strawberries, the formation of colonies and mycelial growth of P. expansum isolates on fruit puree agar media (PAMs) was stimulated in comparison to a standard growth medium (malt extract agar, MEA). Two of the most aggressive isolates in our assays (I 12 and C 28) showed the greatest accumulation of patulin both in vitro and in vivo, while the least aggressive isolate (I 1) produced patulin only in a few growth media and cvs. Patulin concentration on fruit PAMs was higher than patulin detected in infected fruit tissues. Apple PAMs were the more favorable substrates for patulin accumulation in vitro (maximum concentration 173.1 and 74.1 μg/mL in ‘Pink Lady and ‘Golden Delicious’ PAMs, respectively) and ‘Pink Lady’ apples inoculated with the isolate E 11 showed the greatest accumulation of patulin in the whole in vivo assay (33.9 μg/mL). However, infected tissue of cv Golden Delicious showed lower average accumulation of patulin (1.7 μg/mL) than that of cv Pink Lady (19.1 μg/mL), and no significant differences in patulin concentrations were found among ‘Golden Delicious’ apples and tested cvs of pears, kiwifruits and strawberries. Peaches were highly susceptible to patulin accumulation, showing average concentrations of 27.4 and 18.6 μg/mL in vitro and in vivo, respectively. Apricots were also consistently positive for patulin accumulation, both in vitro (average values of 20.1 μg/mL) and in vivo (average values of 9.4 μg/mL). Our study showed the potential of some less common hosts of P. expansum (in particular peaches and apricots) to support patulin production, indicating that a steady monitoring of patulin contamination should be carried out in fruit substrates other than apples and pears.  相似文献   

20.
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