不同品种牛肉品质特性概述

牛肉是重要的畜牧业产品之一,了解不同品种牛的肉质特性,对于合理地开发利用我国的肉牛资源以及保障牛肉品质有重要的参考作用。文中总结了我国三大类型肉用牛(包括牦牛、水牛以及黄牛)肉的食用品质(嫩度、肉色、保水性等)、营养品质(蛋白质、脂肪、水分)、肌纤维特性的研究现状。发现相对比于水牛和牦牛,黄牛肉较嫩,肉色较好,深受人们喜欢;牦牛肉蛋白质含量较高,脂肪含量低,也符合人们对肉质的要求。     

牛肉分级标准及分级技术发展概况综述

我国肉牛业起步较晚,肉质较差,高档牛肉的生产无法满足国内市场日益增长的需求。我国尚未真正实施统一的牛肉等级评价体系,无法形成以质论价、优质优价的优良市场机制,制约我国肉牛产业发展。而肉牛产业发达国家很早就开始推行牛肉分级制度,各自拥有一套适合本国肉牛业发展的牛肉等级评价体系,是各国肉牛产业发展的重要保障。本文在对肉牛业发达国家的牛肉分级标准和先进牛肉自动分级技术进行概述的基础上,针对我国牛肉分级标准和分级技术的研究发展现状,提出适合我国国情的牛肉分级研究及开展分级工作的建议。     

皮尔蒙特牛肉化学组成及肉品品质

就意大利皮尔蒙特牛牛肉的化学组成和肉品品质研究结果进行了综述,并将这些与其它一些肉牛品种、乳用品种以及杂种研究结果进行了对比分析,以便为我国不同地区肉牛改良工作提供启示.     

牛胴体分割增值及品质评价研究概况

提高牛肉价值和品质是肉牛产业发展的关键问题。本文综述了牛胴体分割增值及品质提升的研究现状,并对牛肉品质评价方法进行了叙述。     

基于计算机视觉的牛肉质量分级研究进展

牛肉品质分级对于肉牛产业具有重要意义,为克服人工评级的弊端,客观、无损的自动分级技术成为研究热点。本文综述了国内外利用计算机视觉对牛肉大理石纹、生理成熟度、肉色和脂肪色这些指标进行分级预测的研究进展情况,讨论了研究过程中诸如图像分割、特征提取方面存在的困难,最后指出了计算机视觉技术在牛肉品质分级应用过程中存在的问题以及可能的发展方向。     

我国肉牛生产现状及存在问题调查

随着农业产业结构和食物结构的变化,肉牛产业在我国农业和食品消费中的地位将发生变化,分析和预测这种变化,对肉牛产业的稳定和健康发展具有现实的指导意义.调查在系统分析了我国2001～2005年主要养牛省份牛存栏数、牛肉产量及牛肉商品率发展状况的基础上,结合作者在全国肉牛产区多次调研,探讨肉牛生产中存在的问题和潜在风险,以及肉牛产业健康发展与食品安全的关系,并针对我国肉牛产业发展的问题和潜在风险提出建议,提防大的产业波动.     

国内首批放心牛肉登陆北京超市

2007年2月11日，我国首批基于无线射频识别技术（RFID）进行肉牛全程质量安全追溯管理的放心牛肉登陆首都超市。老百姓可以采用手机拍照、现场查询和登陆网站等多种方式对牛肉进行追溯查询。RFID肉牛全程质量安全追溯管理系统是国家重点科技应用项目——农业部“948”项目的重要组成部分。该系统由中国农业大学和北京华芯同源科技有限公司研制。通过该系统查询，能够了解到牛肉来自哪一个牧场，以及牛的品种、牛龄、疫病和喂养饲料等关系到牛肉品质和安全的信息，并且能了解到影响牛肉质量和安全的相关组织和责任人。     

信息报道

国内首批放心牛肉登陆北京超市2007年2月11日,我国首批基于无线射频识别技术(RFID)进行肉牛全程质量安全追溯管理的放心牛肉登陆首都超市。老百姓可以采用手机拍照、现场查询和登陆网站等多种方式对牛肉进行追溯查询。RFID肉牛全程质量安全追溯管理系统是国家重点科技应用项目———农业部“948”项目的重要组成部分。该系统由中国农业大学和北京华芯同源科技有限公司研制。通过该系统查询,能够了解到牛肉来自哪一个牧场,以及牛的品种、牛龄、疫病和喂养饲料等关系到牛肉品质和安全的信息,并且能了解到影响牛肉质量和安全的相关组织和责…     

电刺激对牛肉品质影响研究进展

电刺激是一种通过给畜禽胴体进行电流刺激而加快肉类成熟的技术。该项技术对于宰后牛肉品质有重要影响。目前已有学者对电刺激的作用机理进行了广泛研究,最近在pH-温度窗口理论以及电刺激对肉色和保水性的影响方面有了最新进展。文中首先介绍了pH-温度窗口理论,随后总结了电刺激对胴体的pH值变化、细胞骨架蛋白降解以及肌原纤维结构变化等方面的影响及因此对牛肉品质产生的影响,以此对国内肉牛屠宰企业合理运用电刺激技术提供理论指导。     

基于BMY牛的肉品质评价指标及其影响因素

以BMY杂交牛为主要参考对象,对几项主要牛肉品质评价指标及影响因素进行分析概述。结果表明:评价牛肉品质的优劣与各项评价指标密切相关,改善牛的个体因素、饲养管理和屠宰因素以及日粮营养等因素能够大大提高牛肉品质,使我国肉牛养殖厂能够找到合理调控肉品质的因素,为我国生产优质牛肉提供参考。     

中国肉牛产业的现状和发展趋势

本文介绍了我国肉牛产业的现状,并与国外肉牛产业的状况进行了比较,提出了今后的发展方向。     

犊牛肉开发现状与影响因素

本文简要介绍了犊牛肉的分类及中国犊牛肉产业发展现状,阐明了影响犊牛肉产业发展的因素,提出了利用先进的犊牛肉生产方式改变我国犊牛利用率低的现状,提高我国牛肉生产资源利用效益,促进肉牛养殖业向优质高效商品化生产发展。     

Do indigenous Southern African cattle breeds have the right genetics for commercial production of quality meat?

The establishment of cattle breeds which are now indigenous to Africa is believed by historians to be very closely associated with man, his development, migration and specific behaviour from 6000 years BC. Today these breeds compete with exotic breeds in a commercial system driven by global economical principles. Results from various trials are discussed to verify if these breeds can adhere to these principles and compete in the South African beef market to produce quality beef economically. Variation in frame size among indigenous breeds will determine their suitability as feedlot cattle depending on the price and feed margins driving profit in this industry sector. Meat quality analyses indicate small or no differences between indigenous and exotic European/British breeds but with potentially superior quality compared to Bos indicus breeds.     

Development of discrimination SNP markers for Hanwoo (Korean native cattle)

In the Korean meat market, the native cattle, Hanwoo beef, are preferred over imported beef and domestic Holstein beef despite its relatively high price. In order to hold the beef industry accountable and support consumers' right to know, correct beef-origin labeling is required. For this purpose, we developed 90 single-nucleotide polymorphism markers to discriminate between Hanwoo and other breeds including Holstein using 1602 cattle DNAs. The probability of discrimination was found to be 100% in a subsequent validation set consisting of 632 DNAs. Our study suggests that improved beef-origin discrimination can be achieved by using a combined genetic model that takes into account small genetic differences among a large number of markers. These markers could be useful for discriminating between Hanwoo and imported breeds including domestic Holsteins, and would contribute to the prevention of falsified beef origin.     

秦川公牛与鲁西公牛牛肉感官品质和加工特性

研究秦川公牛和鲁西公牛的西冷和牛霖的感官品质和加工特性。结果表明：鲁西公牛肉色的亮度值(L*)和红度值(a*)显著大于秦川公牛的(P＜0.05);秦川公牛与鲁西公牛牛肉的多汁性和剪切力值均无显著差异;秦川公牛西冷牛肉的滴水损失和蒸煮损失分别为1.33%和30.76%,显著低于鲁西公牛的2.12%和48.30%(P＜0.05);秦川公牛牛肉的凝胶特性优于鲁西公牛;鲁西公牛牛肉的乳化特性优于秦川公牛。秦川牛肉适宜加工凝胶类制品,而鲁西黄牛肉适宜加工乳化类制品。     

DGAT1 polymorphism in Bos indicus and Bos taurus cattle breeds

As a result of multiple QTL-mapping projects in recent years, a quantitative trait locus for milk fat percentage and milk yield has been described on BTA14. Recent reports name the acyl-CoA : diacylglycerol acyltransferase (DGAT1) gene on BTA14 as a potential candidate gene, with a nonconservative substitution of lysine by alanine (K232A) producing a major effect on milk composition and yield. DGAT1K appears to be the ancestral allele and the K232A substitution probably occurred after the divergence of the Bos indicus and Bos taurus lineages. These findings prompted us to genotype 1748 DNA samples of 38 different Bos taurus and Bos indicus cattle breeds from 13 countries on five continents (Europe, Africa, Asia, North America and South America), to examine the occurrence of the DGAT1 polymorphism and characterize the K232A substitution in cattle breeds of different origins and selected for different purposes (e.g., beef, dairy and dual purpose). Calculating pairwise FST values for pooled subpopulations showed least divergence for Bos indicus breeds with high milk fat percentage. Fixation of DGAT1A was found in some Bos taurus breeds and fixation of DGAT1K in one Bos indicus breed. Breeds of no known organized breeding background from the Near East domestication centre of Bos taurus and taurine African N'Dama cattle were found to possess intermediate frequencies of DGAT1K. While beef breeds tended to harbour higher DGAT1A levels, dairy cattle showed everything from very low levels of DGAT1K to unexpectedly high frequencies of this allele.     

丰都县肉牛产业发展现状

重庆市丰都县位于三峡库区,水源充足、牧草资源丰富,素有黄牛养殖传统.该县拥有亚洲单体养殖规模最大的标准化1.5万头肉牛育肥场,具有全国最大的肉牛养殖基础.目前,丰都县正全力打造“中国肉牛之乡”,并以肉牛作为农民万元增收的主导产业,促进地方经济发展.本文主要对丰都县肉牛产业链的发展现状作综合阐述.     

不同坡度装卸台装卸牛对牛肉品质的影响

为研究不同坡度的装卸台装卸牛对牛肉品质的影响,选取西门塔尔肉牛20头,随机分为4组,各组分别通过(30,40,50°)坡度装卸台装卸牛后,然后对牛进行屠宰,分析宰后牛肉pH值、肉色、失水率、蒸煮损失率和剪切力。结果表明:随着装卸台坡度的增大,宰后牛肉pH值、牛肉L*值、a*值呈下降趋势(P0.05),牛肉b*值、剪切力、肉失水率、蒸煮损失率呈增加趋势(P0.05)。通过坡度为30°的装卸台装卸牛,宰后牛肉品质较好,在实际生产中应降低装卸台坡度,以提高牛肉品质。     

九种本地雪花黄牛肉消费者感官评价及品质预测模型构建

为挖掘国内优质黄牛肉的品质特性,了解其市场定位和产品开发方向,以进口雪花牛肉作为对照,开展了9种本地A3级雪花黄牛肉生鲜肉、煎制肉和涮制肉的消费者感官评定。结果表明:郏县红牛、新疆褐牛、渤海黑牛3个品种背最长肌煎制肉从多汁性、滋味、嫩度、色泽、残渣及香气评价与进口A3级雪花牛肉无显著差异（P>0.05）,9个品种本地黄牛股二头肌涮制肉均能达到进口雪花牛肉水平,其中渤海黑牛、平凉红牛、云岭牛、夷陵牛、晋南牛股二头肌涮制肉得分显著高于进口雪花牛肉（P<0.05）。对比生鲜肉和熟制肉的感官评价结果发现二者相关性偏低（r=0.345）,说明仅凭生鲜肉外观确定牛肉质量等级存在一定的偏差,因此本研究进一步开展背最长肌理化指标的测定并与感官得分进行线性回归分析,构建了牛肉品质预测模型,结果显示生鲜肉排整体可接受性=6.382?0.132×蛋白质含量,煎制肉整体可接受性=4.751?0.228×剪切力,生鲜肉的回归方程可以解释81.2%的因变量变异,煎制肉回归方程可以解释62.6%的因变量变异,模型拟合程度良好。通过筛选蛋白质和剪切力分别作为生鲜肉和煎制肉的评定指标,为牛肉品质评价提供了新的参考依据。     

Growth,carcass traits and palatability: Can the influence of the feeding regimes explain the variability found on those attributes in different Uruguayan genotypes?

It is well known what genetic and nutritional factors affect growth and meat quality, but there is less information related to interactive importance of them during the productive process. These systems are mainly based on rangelands affecting animal growth in early stages of life thus producing smaller cattle and reduced retail yield comparing with well grown calves. During the last ten years, Uruguayan livestock production systems have been intensified using improved pastures, concentrates and better genetic. The main breeds in Uruguay are Hereford, Angus and their crosses. These British breeds are under genetic evaluation programs which consider carcass trait parameters. It is important for beef industry to know if interactions between genotype and nutrition during growth and fattening phases are influencing production, efficiency, carcass weight and meat quality attributes. The aim of this article is to present information obtained under different feeding strategies during the post weaning and fattening and their influence on those attributes.