首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
The gross, proximate, fatty acids and cholesterol composition of three raw retail cuts from 28 lambs classified by weight, sex and fatness score were investigated. For gross composition, cut weight increased significantly with fat score and carcass weight. Percentage fat increased significantly from fat score 1–2 but not beyond (P<0.05). For nutrient composition the fat contents of the total cut and lean only portion of the three cuts increased directly with fat score by 10 g/100 g and 1.7 g/100 g, respectively. Fat content increased mainly at the expense of moisture. Cholesterol content of total cut and lean only portions decreased with increased fat score, by 16 and 18 mg/100 g, respectively. For lean only levels of myristic and palmitic acids increased significantly (P<0.05) while stearic acid decreased significantly, while levels of linoleic and linolenic acids decreased significantly with increased fat score.  相似文献   

2.
Various post-mortem measurements (carcass weights, conformation and fatness classes, external carcass dimensions, eye muscle dimensions, subcutaneous fat depth, pH and temperature) were recorded on 197 Texel (TEX) and 200 Scottish Blackface (SBF) lamb carcasses. The potential use of these measurements to predict carcass composition and key meat quality traits was investigated, to enable categorisation of carcasses in the abattoir and/or for use in genetic improvement programmes. By combining different measurements, accurate predictions of dissected carcass muscle weight (adjusted R2 0.93 in TEX, 0.88 in SBF) and fat weight (adjusted R2 0.84 in TEX, 0.87 in SBF) were achieved, and moderate predictions of intra-muscular fat (adjusted R2 0.56 in TEX, 0.48 in SBF), whilst shear force was predicted with low to moderate accuracy (adjusted R2 < 0.33 across breeds and cuts). Sex, eye muscle dimensions and subcutaneous fat depth improved predictions of carcass composition and intra-muscular fat, whilst pH or temperature provided little additional benefit for these traits, but increased prediction accuracies for shear force. These results could contribute to the development of automated carcass grading systems or help inform breeding decisions.  相似文献   

3.
One hundred and twenty carcasses were sampled to compare different techniques or methods for prediction of lamb carcass composition and value. Four methods that are used at the Norwegian Meat Research Centre, Animalia, were selected. These were the basic EUROP classification, the advanced EUROP classification using carcass shape and length measurements, visible light reflectance probing (GP) and Computer Tomography (CT). The different technologies were tested using an iterative approach, selecting calibration and validation data sets from the 120 carcasses randomly, where 90 carcasses were used for calibration, and 30 for validation. The best prediction models were obtained using CT, with respect to prediction error and correlation between predicted and measured value of carcass fat and muscle (in kg), and value (in NOK). Due to high cost and low operating speeds of CT, optical probing (GP) may be the second best solution of the technologies used in this study, combined with a CT dissection reference as an alternative to manual dissection.  相似文献   

4.
This study evaluated the effects of the myostatin g + 6723G > A mutation on carcass and meat quality traits of lamb (AA: n = 5; AG: n = 8; GG: n = 9). Dressing percentage was positively affected by the mutation with homozygotes for the mutation having the highest yield. Regarding carcass composition, there was a significant increase in the proportional weights of the loin and hindquarter muscles. Objective meat quality traits of the M. longissimus lumborum (LL) and M. semimembranosus (SM) were not significantly affected. For the SM, toughness (shear force and compression) tended to be lowest for homozygotes for the mutation. The myostatin g + 6723G > A mutation did not affect sensory meat quality traits of grilled steaks for the LL, but resulted in a significant improvement in eating quality for the SM. Given the number of animals in this study, the robustness of the outcome of this study with regard to the effects on meat quality and its causes requires further investigation.  相似文献   

5.
This experiment was designed to describe the accuracy of the EU-reference dissection method, and to describe the types of factors influencing the accuracy and assess their size. The experiment was conducted in four different European countries at two abattoirs within each country. A total of 128 carcasses was selected according to carcass weight, fat class and sex, and 8 butchers from different countries dissected the carcasses. Due to the experimental design of the experiment a variation in pig type was found between countries. The accuracy was expressed by the repeatability and reproducibility standard deviation, which were found to be 0.87 and 1.10, respectively, and by the reliability, found to be 0.87. This indicates a high accuracy, although a significant effect was found on the estimation of lean meat percentage (LMP) of butcher, and also that jointing of the carcass was of overall importance to the accuracy of the EU-reference dissection method.  相似文献   

6.
7.
Wolf BT  Jones DA  Owen MG 《Meat science》2006,74(2):416-423
A subjective assessment of the shape of the hind limb of purebred Texel lambs was evaluated as an in vivo predictor of carcass composition and muscularity. Lambs were taken from two flocks that were managed in a common environment, but which had either been selected for lean tissue growth rate or for improved conformation. Lambs were slaughtered at a mean age of 139 days at the end of an 11 week performance test in which they were reared indoors on a concentrate diet. Pre-slaughter measurements of live weight and ultrasonic muscle (UMD) and fat (UFD) depths at the position of the third lumbar vertebra, body length (L) and a subjective leg shape score were recorded. After slaughter, measurements were recorded for carcass side length (SL), leg length (T) and the maximum width (A) and depth (B) of the longissimus thoracis and lumborum (LTL) muscle. The side was fully dissected and various muscle weights and skeletal dimensions were used to calculate indices of muscularity as √(muscle weight/length) per unit length or as UMD/L, A/SL or B/SL. The leg shape score was positively correlated with lean weight (0.23) and proportion (0.24), lean:bone ratio (0.25), measures of LTL dimensions (0.27-0.38) and muscularity traits (0.27-0.57) but was not significantly (P>0.05) correlated with fat weights or proportions in the carcass. Live weight was the best single predictor of lean weight (RSD=0.403) and the addition of leg shape score (RSD=0.381) to prediction equations was less effective than the inclusion of UMD and UFD in combination (RSD=0.357). The addition of leg shape score to equations that included ultrasonic traits gave a significant (P<0.05) but marginal improvement in prediction (RSD=0.347). The leg shape score was the most useful in vivo predictor of carcass muscularity traits and, with R(2) in the range 0.30-0.50, had comparable predictive power to a leg muscularity score derived from muscle weight and femur length. It is concluded that the leg shape score showed potential as a predictor of carcass muscularity that was largely independent of live weight and fatness at a fixed age and was marginally associated with superior lean yield and lean:bone ratio.  相似文献   

8.
Growth, carcass yield and proximate composition were determined in intensively reared nutria (Myocastor coypus) fed different levels of protein. Growth, food intake and food utilization efficiency were not significantly affected, within the same sex, in animals receiving 16%, 19% or 22% of protein in the diet. Males consumed the same amount of food as females but had greater live and carcass weights at slaughter age than females. Males had the highest meat yield and females had the highest fat content. Independent of dietary protein level, the pectoral muscles of all animals ranged from 19.2% to 23.6% protein, 1.97% to 2.47% total lipids, and 70.1 to 72.0mg of cholesterol in 100g of tissue. In the thigh muscles, the observed ranges were between 21.4% and 22.9% in proteins, 1.83% and 2.07 in total lipids and 69.9 and 71.0mg of cholesterol in 100g of tissue. The determination of classes of lipids shows more phospholipids contents in animals receiving 16% of protein in diet.  相似文献   

9.
The melanocortin-4 receptor (MC4R) is involved in feed intake regulation. A missense mutation G/A in position 1426, which causes Asp-Asn substitution at position 298 in the MC4R gene has been associated with feed intake, fatness and growth, however published results of its effect are inconsistent. In our study we evaluated an effect of missense mutations on carcass composition, growth traits and meat quality in 1191 gilts of five breeds: Polish Large White, Polish Landrace, Pu?awska, Pietrain and Duroc. G/A 1426 MC4R mutations were genotyped using a 7500 Real-Time PCR System (Applied Biosystem). Our observations confirm that the G allele is frequent in breeds selected for lean meat content (Pietrain – 92.4%) and rare in breed with a fat carcass (Duroc – 31.5%), which has been previously reported. Our study revealed that the A allele was associated with increased daily feed intake (AA – 2.51 kg; GG – 2.31 kg in the Pu?awska breed, P < 0.05), daily gain and backfat thickness (AA – 1.67 cm, GG – 1.52 cm in PL, P < 0.01) and decreased lean meat content (total weight of ham was 0.5 kg greater in G/G than in A/A Pu?awska animals). We obtained an unexpected result for IMF: higher percentage of IMF was observed in the G/G genotype.  相似文献   

10.
Food selection and consumption can be affected by different intrinsic and extrinsic cues. In this study, the effect of three extrinsic cues (country of origin, price and feeding system) on consumer’s purchasing decisions making process for lamb meat in three European countries: Spain, France and United Kingdom was investigated, as well as the relative importance of each cue. Four countries were considered for evaluating the effect of the country of origin (local, Argentina, Switzerland and Uruguay), three feeding systems (grain-fed, grass-fed and grain + grass-fed) and different price levels (low, medium and high), which were simultaneously compared. Fifteen profiles combining the different levels for each of the factors considered where those obtained by means of an orthogonal design. These profiles were evaluated by 100, 99 and 92 consumers in Spain, France and United Kingdom, respectively. Moreover, consumers sensory evaluated lamb from four different feeding systems, grain-fed, grass-fed and two mixtures of grain and grass-fed. Conjoint analysis was carried out both for evaluating clusters of consumers in each country and for considering an overall evaluation of all the countries at the same time. In general, the origin of the meat was the most important factor in determining consumer’s purchasing decisions making process, the local one being the most preferred. Uruguayan origin was the least preferred, which indicates that Uruguayan public and private sectors would need to enhance their country and meat image as well as support market promotion and penetration strategies in the European market. For some consumers the feeding system was the most important factor for choosing any particular meat amongst others, being grass-fed animal the most preferred. These results are not in agreement with the consumer’s acceptability studies of lamb meat when taste the meat from different feeding systems in a blind condition (without information), showing a disconfirmation. Lamb meat price has a minor role in determining consumer’s purchasing decisions. However, one segment of consumers, composed mainly by men, considered that the price is the most important factor. These findings showed the importance of studying consumer preferences and their segmentation for developing market promotions, which should have a holistic approach including extrinsic factors in the evaluation of consumer’s purchasing decisions making process.  相似文献   

11.
Li Wang  Frank S.C. Lee 《LWT》2007,40(1):83-88
Licorice, the roots of Glycyrrhizia uralensis Fisch, is used as a medicinal herb and food additive in China. At present, the quality grading and authentication of licorice products is generally done by visual inspection, which is subjective and often biased. In this study, a rapid and nondestructive method for the classification of licorice samples according to their growing conditions, geographic areas and plant parts was developed using fiber optic diffuse reflectance near-infrared spectroscopy (FODR-NIR). With the use of multiplicative signal correlation (MSC) and Norris derivative filter, the differences of the NIR spectra among different licorice samples were enhanced even though the raw spectra were very similar. The results showed that the NIR spectra of the samples were moderately clustered in the principle component spaces, and pattern recognition technique of soft independent modeling of class analogy (SIMCA) provided satisfactory classification results. Additionally, a partial least square (PLS) method using HPLC data set as reference was constructed to predict the value of glycyrrhizic acid (GA) in licorice. The results showed that PLS models with both data normalization (DN) coupled with first derivative pretreatments, and MSC coupled with first derivative pretreatments provided acceptable results.  相似文献   

12.
Association mapping of the central part of porcine chromosome 2 harboring QTLs for carcass and meat quality traits was performed with 17 gene-tagged SNPs located between 44.0 and 77.5 Mb on a physical map (Sscrofa10.2) in Italian Large White pigs. For the analyzed animals records of estimated breeding values for average daily gain, back fat thickness, lean cuts, ham weight, feed conversion ratio, pH1, pHu, CIE L*, CIE a*, CIE b* and drip loss were available. A significant QTL for fat deposition (adjusted P = 0.0081) and pH1 (adjusted P = 0.0972) to MYOD1 at position 44.4 Mb and a QTL for growth and meatiness (adjusted P = 0.0238–0.0601) to UBL5 at position 68.9 Mb were mapped. These results from association mapping are much more accurate than those from linkage mapping and facilitate further search for position candidate genes and causative mutations needed for application of markers through marker assisted selection.  相似文献   

13.
国内外食品质量安全状况评价体系分析   总被引:1,自引:1,他引:1  
从系统评估产生出发,简述了食品安全状况评价的发展历史和国内外现状,重点分析了国外的评价方法和数学模型。食品安全状况系统评价创立于20世纪90年代末,评价框架思路基于CAC创导的食品风险分析,评价方法和数学模型多样化,国内以模糊综合评判为主,注重整体状况的安全评价;国外主要有剂量-反应关系的生物学模型、概率暴露评估模型、决策评估法和相对潜力因素评估模型,注重化学物和生物危害物的暴露风险评估;实质等同原则用于新食品和遗传修饰食品安全性评估。   相似文献   

14.
 An assessment system using various microbial methods was developed for the detection of residual, surface-attached microbes and soil on surfaces after sanitation. The microbial methods tested were: conventional cultivation, microscopy using image analysis after staining with acridine orange (AO), 5-cyano-2,3-ditolyl tetrazolium chloride/4′, 6-diamidino-2-phenylindole (CTC-DAPI) and LIVE/DEAD stains, impedance measurements, viable counts with 2,3,5-triphenyltetrazolium chloride (TTC) agar and ATP measurements. A test rig was used for the trials with four different low-pressure cleaning procedures (pressure <20 bar flow rate 27 l min–1). A strong alkaline foam cleaner, Trippel, and a mild alkaline foam cleaner, Topax 12, in combination with two disinfectants, respectively, were used. The disinfectants were peroxide-peracetic-acid-based Oxonia Aktiv and potassium-persulphate-based Virkon. Conventional cultivation combined with impedance measurements and image analysis of surfaces stained with AO, as well as CTC-DAPI, gave results that were comparable and complementary. The combination of these methods enabled a total evaluation of both the removal of biofilm and the killing of bacterial cells. The low-pressure cleaning system did not remove all of the bacterial cells from the surfaces and did not kill the bacteria even after use of the strong alkaline foam cleaner. The above-mentioned protocol carried out on the test rig can also be used to evaluate the sensitivity of microbial methods for use in certain industrial premises. Received: 22 July 1998 / Revised version: 14 September 1998  相似文献   

15.
16.
Croatian traditional cheese, which ripens in a lamb skin sack, was studied to determine compositional, biochemical and sensory changes over 60 days of ripening. The ripening time had a significant effect on the chemical, biochemical and sensory parameters, particularly on the medium‐ and long‐chain free fatty acids (< 0.05) and total FFAs (< 0.001). At the end of ripening palmitic, oleic and stearic acids were the predominant FFAs. Cheese ripened for more than 45 days was less acceptable to consumers as a consequence of extensive proteolysis and lipolysis. Therefore, ripening for more than 45 days, which is commonly practised by cheesemakers, is not recommended.  相似文献   

17.
Prediction equations for the percentage lean meat in pig carcasses in The Netherlands were derived for the Hennessy Grading Probe 7, Capteur Gras/Maigre — Sydel and CSB-Image-Meater. Because castrated males are expected to vanish from the Dutch pig population in the near future, accuracy of prediction was evaluated for different scenarios representing a wide range of different proportions for entire males, castrated males and females in the Dutch pig population. The prediction equations for the instruments are in compliance with the EC regulations for prediction accuracy for the different scenarios. So, these equations will remain valid when castrated males are (gradually) removed from the Dutch slaughter population. Results of this study are of interest for researchers from countries or areas contemplating the use of one of the aforementioned instruments. The statistical approach for evaluation of prediction accuracy is of particular interest when changes in proportions of important subpopulations in the target population are foreseen.  相似文献   

18.
This study aimed to establish an analytical method for α‐dicarbonyl compounds (α‐DCs) including glyoxal, methylglyoxal and diacetyl, to determine the content of α‐DCs in 101 various alcoholic beverages using gas chromatography–nitrogen phosphorous detector (GC‐NPD) and to perform exposure assessment. The limit of detection and limit of quantification for α‐DCs were 0.05–0.22 and 0.15–0.70 μg g?1, respectively. The accuracy and precision were validated in five matrices. The raspberry fruit wine had the highest value at 139.74 μg g?1 total α‐DCs. The lowest α‐DC concentration among the beverages was detected in rice wine (Makgeolli) at 1.59 μg g?1. The levels of α‐DCs in various samples were detected as follows: 1.59–56.68 μg g?1 in rice wine (Makgeolli), 2.73–16.77 μg g?1 in beer, 8.22–139.74 μg g?1 in fruit wine and 8.17–91.56 μg g?1 in rice wine (Cheongju). The estimated daily intake of α‐DCs in the intake‐only group and population group was calculated as 4.22–97.94 μg kg?1 bw day?1 and 0.28–7.13 μg kg?1 bw day?1, respectively.  相似文献   

19.
Accra Metropolis is the major recipient of agricultural produce in Ghana, with almost the entire population depending on rural agricultural activities for subsistence. To increase agricultural produce, various forms of pesticides are normally used in fruits and vegetable farming. The consequence is that several cases of pesticide poisoning have been observed. In this preliminary study, a field survey was carried out to assess the knowledge, attitudes, and peoples’ perception concerning the use of pesticides by farmers in fruit production. The residual concentrations of selected pesticides in pawpaw, imported apples and tomato samples and the potential health risks associated with the exposure to these pesticides were also assessed. The field survey data indicated that more than 70% of the participants reported one or more poisoning upon fruits consumption resulting in pesticide-related illnesses. Pesticide residues in the various environmental samples were determined by gas chromatography with electron capture detector (GC-ECD). The results showed that, the levels of pesticide residues varied from <0.01 μg/g to as high as 0.11 μg/g depending on the pesticide monitored. The analysis of health risk estimates revealed heptachlor, heptachlor epoxide, endrin aldehyde, and endrin ketone levels exceeded the reference dose, suggesting a great potential for systemic toxicity in children considered the most vulnerable population subgroup. Lastly, the public is in the know of pesticide residues in fruits and calls for the curtailing of pesticide use on fruits and vegetable production via educational programmes for farmers on control and safer use of pesticides.  相似文献   

20.
With the advancement of skin research, today's consumer has increased access to an informed understanding of ageing skin and its appendages, together with a plethora of targeted products to meet such needs. In recent years, increased legislative demands for quality evidential claims support have led not only to the development and validation of clinical methods to measure and quantify ageing skin, but also a clearer understanding of the skin ageing process–especially the impact of both its internal and external environments–as well as a tougher stance on clearly unjustifiable claims. Traditional testing methods used to research and evaluate anti‐ageing products claim to employ sophisticated instruments. Today, however, since the term anti‐ageing can be considered a misnomer, intelligent use of combined more advanced clinical methods has enabled the development of technologically improved consumer products providing enhanced efficacy and targeted performance. Non‐invasive methods for the assessment and quantification of the causes of ageing skin provide tools to the clinical researcher as defined by key clinically observed ageing parameters. Where evidence requires additional support, a number of clinical procedures evaluating ageing skin and hair products are combined with invasive procedures, thus enabling an added value to product claims. As discussed herein, given the enhanced understanding of ageing, we provide an update to our previous reviews of clinical methods used in the assessment of skin ageing, to include the wider aspects of environmental exposure; skin pigmentation; microbiome disturbance; surface topography; colour, radiance, and pH; and structural integrity–all requiring a disciplined approach to their use in dermatological investigations and product claims evidence.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号