化零为整——探讨影响凝血酶/血纤维蛋白凝胶粘合度的因素

<正> 从牛、小牛、猪和羊等家畜及家禽类得到的肉,以及在分割胴体时得到的肉,在质量上常常出现很大的差异。因此,我们会根据肉品的种类、肉块大小、脂肪含量、结缔组织含量以及市场的需求等因素,将不同的肉类原材料制造成各式各样的肉制品。一般来说,     

猪胴体智能分级技术研究进展

猪胴体智能分级技术是屠宰行业关注的热点,本文概述了猪胴体分级技术的发展历史、现状和发展趋势,并根据我国的现状提出了一些建议。     

猪胴体分级技术研究进展

猪胴体分级是指根据猪胴体的一些相关经济性状，人为的将其划分为不同的等级，从而实现优质优价，促进商品猪品质的提高。本文概述了国内外猪胴体分级技术的发展历史、现状及未来的发展方向，并为建立一套符合我国国情的快速、简便、准确的猪胴体等级评定体系提出了设想。     

国内外猪胴体分级标准体系的现状与发展趋势

文中从探索建立适合我国国情的猪胴体分级体系,实现优质优价,促进我国商品猪品质提高的角度出发,较系统的概括了各国猪胴体分级标准的发展历史、现状及未来的发展方向。并且,根据我国的胴体分级现状提出了一些具体设想。     

加快我国肉牛胴体评定方法的研究

笔者阐述了牛胴体评定和分级的意义及影响牛胴体质量的关键因素,对美国、日本、EEC、加拿大等国的牛胴体分级标准进行了介绍,并对我国在制订牛胴体分级标准时应注意的问题进行了探讨。     

肉品质量控制的技术保证——肉类品质无损检测技术

肉品的品质评定以及胴体(猪、牛、羊等)分级是肉品质量研究的主要内容。对肉的食用品质的评定一般从肉色、嫩度、风味、系水力、多汁性等方面来衡量,检测方法多用化学、物理以及口感等破坏性检测手段。胴体分级根据具体对象的不同有所区别,但通常有质量级和产量级的区分。目前,     

我国屠宰企业猪胴体分级技术的研究进展与建议

文中叙述了研究猪肉品质的重要性,介绍了国内外的猪胴体分级标准,综述了多种检测猪肉品质的先进技术和方法,描述了利用计算机视觉技术获取多指标、多特征研究猪肉品质是我国屠宰企业猪胴体分级的发展趋势。     

畜禽胴体分级技术

概述了畜禽胴体分级的重要性,介绍了美国、加拿大等国家畜胴体分级的标准和四种主流自动化分级技术,重点论述了目前世界上主要的家畜和家禽分级设备研究和应用情况。     

猪肉的分级、分割及分割肉加工

猪肉的质量差异很大,应对猪肉进行分级,并分割使用.猪肉可按胴体的肌肉发达程度以及脂肪的厚薄和按胴体不同部位肌肉的组织结构、食用价值和加工用途两种方法分级,均有三个等级.猪胴体可切割为前腿肉、大排肉、方肉、奶脯、后腿肉和蹄膀等6个部位肉;分割肉加工主要包括白条肉预冷、三段锯分、小块分割与修整、快速冷却、包装和冻结等工序.     

北京地区三元杂交猪胴体的分级优化

为了提高猪胴体分级的准确性,利用计算机视觉技术、图像处理技术及统计分析方法,对已建立的猪胴体分级标准及预测方程进行修订.结果表明:以左半胴体质量、臀中肌横长和臀中肌膘厚预测瘦肉率绝对误差小于4%;同时以瘦肉率、臀中肌膘厚、1/2横长处膘厚及6~7肋处膘厚等特征作为分级主要参数,使分级准确率达90%.将各处膘厚与瘦肉率相结合,并对猪胴体级别根据实际需求进行调整,可使分级工作更加合理,准确性也有提高.     

延边黄牛胴体质量等级的完善及不同等级肉质比较

对延边黄牛胴体质量等级进行完善,为胴体等级标准的建立提供前提条件,并比较不同等级延边黄牛肉肉质差异.结果表明:不同质量等级延边黄牛肉中水分、粗蛋白和粗灰分含量各组间均无显著差异,粗脂肪含量差异显著(P<0.05).不同质量等级延边黄牛肉中失水率、系水率、熟肉率、剪切力差异显著(P<0.05).牛肉质量等级越高,熟肉率和系水率越高,嫩度越好.     

Effects of metabolic modifiers on carcass traits and meat quality

Much research has been conducted and published about metabolic modifiers that increase growth rate, improve feed efficiency, increase carcass leanness, and decrease carcass fatness. Most of these metabolic modifiers have been developed to improve efficiency and profitability of livestock production and to improve carcass composition, with fewer of them developed and researched specifically to improve meat quality. Some of the metabolic modifiers can have negative effects on visual and sensory meat quality, especially when not used as recommended. This review evaluates the various kinds of metabolic modifiers that have been researched for their effects on production efficiency, carcass composition, and meat quality. Nutritional composition of meat generally is improved from use of most of the metabolic modifiers, visual quality is improved by others, but some can have a negative effect on marbling and tenderness. Anabolic steroid implants are very cost effective and practical for beef cattle production but aggressive implants used within 70 days of slaughter or too frequent use of them will reduce tenderness and marbling. Somatatropin and approved β-agonists are very effective in improving growth performance and carcass leanness in pigs, and β-agonists are effective in cattle, but improper use of them can have negative effects on marbling and tenderness. Feeding supplemental levels of vitamin E is quite beneficial for improving meat color and shelf-life of beef, lamb, and pork, whereas not supplementing diets with vitamin A has potential for improving marbling in cattle. Immunocastration shows promise for capitalizing on the efficiency of muscle growth of young boars up to a few weeks before slaughter, at which time boar taint is prevented and marbling is improved by immunocastration. Potential exists for improving the fatty acid profile of lipids and increasing conjugated linoleic acid content in beef through dietary manipulation. Supplementing swine diets with conjugated linoleic acid can improve carcass composition of swine, but is not yet cost effective to use. Dietary inclusion of magnesium, manganese, or chromium in diets of pigs and sheep has potential to improve meat color and water-holding capacity. Although, not all of these metabolic modifiers are approved in all countries, proper use of the ones that are approved offers opportunities for economically improving production efficiency and carcass leanness while maintaining acceptable marbling and tenderness, while some provide opportunities to enhance meat color and quality.     

How climatic changes could affect meat quality

Climate change could affect meat quality in two ways. First, there are direct effects on organ and muscle metabolism during heat exposure which can persist after slaughter. For example heat stress can increase the risks of pale-soft-exudative meat in pigs and turkeys, heat shortening in broilers, dark cutting beef in cattle and dehydration in most species. Second, changes in livestock and poultry management practices in response to hazards that stem from climate change could indirectly lead to changes in meat quality. For example, changing to heat-tolerant Bos indicus cattle sire lines could lead to tougher, less juicy beef with less marbling. Also, pre-conditioning broilers to heat stress to encourage better survival during transport could lead to more variable breast meat pH_ult. The impacts that short term climate change could have will vary between regions. The ways the impacts are managed need to be based on experience while appreciating the range of approaches that could be used.     

The animal fat paradox and meat quality

The purpose of this paper is to address some of the paradoxical issues and perceptions regarding animal fats and the related effects on meat quality and consumer perceptions. Meat scientists have been studying carcass characteristics for many years and although the factors that influence the accumulation, distribution and composition of carcass fat in livestock have been extensively researched, the role, value and perceptions of animal fats in meat quality differ significantly in importance between producers, abattoirs, butchers, retailers and consumers. Fat and long-chain fatty acids, whether in adipose tissue or muscle, contribute to important aspects of meat quality and are central to the nutritional and sensory values of meat. In this review the nutritional value of fat, as well as the importance of fat in terms of carcass and meat quality will be highlighted. The 'quality' of meat depends greatly on the socio-demographic backgrounds of the consumer. The aim is to focus on the global importance of fat in the carcass to the producer, processor and consumer. There is currently no clear cut definition for fat quality because the acceptability and perceived quality of fat varies significantly in terms of quantity, colour, consistency and chemical composition in different species of livestock around the world. The association between animal fats and human health is critical and recommendations by health professionals range from excluding fats altogether to a moderate consumption of fats due to their essential role in the body. Recently the emphasis has shifted away from fat quantity to fat quality. Despite these recommendations and years of bad publicity in terms of the adverse affects of animal fats in human health, the livestock industry seems reluctant to shift its focus to fat quality rather than quantity. This approach may adversely affect future meat consumption by consumers who are becoming increasingly critical about the food they eat.     

Road transport of cattle, swine and poultry in North America and its impact on animal welfare, carcass and meat quality: a review

This paper reviews the effects of road transport on the welfare, carcass and meat quality of cattle, swine and poultry in North America (NA). The main effects of loading density, trailer microclimate, transport duration, animal size and condition, management factors including bedding, ventilation, handling, facilities, and vehicle design are summarized by species. The main effects listed above all have impacts on welfare (stress, health, injury, fatigue, dehydration, core body temperature, mortality and morbidity) and carcass and meat quality (shrink, bruising, pH, color defects and water losses) to varying degrees. It is clear that the effect of road transport is a multi-factorial problem where a combination of stressors rather than a single factor is responsible for the animal's well-being and meat quality post transport. Animals least fit for transport suffer the greatest losses in terms of welfare and meat quality while market ready animals (in particular cattle and pigs) in good condition appear to have fewer issues. More research is needed to identify the factors or combination of factors with the greatest negative impacts on welfare and meat quality relative to the species, and their size, age and condition under extreme environmental conditions. Future research needs to focus on controlled scientific assessments, under NA conditions, of varying loading densities, trailer design, microclimate, and handling quality during the transport process. Achieving optimal animal well-being, carcass and meat quality will entirely depend on the quality of the animal transport process.     

Influence of physiological status on residues of lipophilic xenobiotics in livestock

Data on the transfer of lipophilic xenobiotics from livestock feed and the environment to meat and milk are required for risk assessment purposes. Often, data are only available for lactating dairy cattle. Physiologically-based pharmacokinetic (PBPK) modeling has been used to explore differences between classes of food-producing animals. Blood and tissue levels of lipophilic xenobiotics under conditions approximating steady-state were simulated. Simulations of constant exposure were performed for lactating cows, non-lactating cattle, sheep, goats and swine. The tissue : blood partition coefficient, fat volume and fat blood flow were identified as critical determinants of predicted tissue concentrations. There may be significant breed differences in residues in milk and fat following exposure. Modeling was used to derive scaling factors that can be used to assist the extrapolation of transfer studies, carried out on lactating dairy cows, to other classes of cattle and different species.     

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.     

肉品品质评定方法研究进展

肉类产业是食品产业的重要支柱,世界范围内肉类的人均年消费量接近30 kg,随着世界经济的不断发展,肉类消费量也具有很大的提升空间。肉品的品质是影响消费意欲的重要因素,肉品品质评定方法的建立对肉类食品的健康发展具有十分重要的意义。目前国内外关于肉品品质的评定方法研究主要是针对猪、牛、鸡、鸭等大宗产品,其中对猪肉、牛肉的品质研究较为全面,有相对完整的评定体系,其他畜禽肉的评定方法则主要参考猪肉和牛肉的指标,考虑到不同物种的差异性,最终的评价结果可能会有较大差异。本文综述了肉色、p H值、系水力和嫩度等主要肉品品质指标的评定方法及相关影响因素,并将不同评定方法的测定条件和结果进行了比较,为肉品品质评定体系的建立及完善提供参考依据。