牛乳酸度指标落后乳业十三五规划提出修订新国标

<正>正常情况下,新鲜挤出的牛乳呈弱酸性。如果酸度偏高,说明牛乳受微生物影响的程度更高;酸度偏低,则表示牛乳更新鲜。所以,酸度是一个代表牛乳新鲜程度的理化指标,通过它可以评判出牛乳的新鲜程度。中国乳业大师金世琳的《乳品工业手册》中就有明确说明:"酸度是反映牛乳新鲜度和热稳定性的重要指标,酸度高的牛乳,新鲜度低,热稳定性差;反之,酸度低表明新鲜度高,热稳定性也高。"国标当中的牛乳酸度则是牛乳自然酸度和发酵酸度的总和。     

生鲜乳品质的影响因子——酸度

酸度是近年来生鲜乳中的重要检测项目之一，酸度的高低直接影响生鲜乳的新鲜度，从而影响生鲜乳的品质。通过综述生鲜乳中酸度的来源、正常范围、酸度不正常的原因．提出了酸度异常的预防措施。     

养殖环节中对奶牛生鲜乳五项指标检测

对民和县马场垣乡的8家奶牛养殖规模户的生鲜乳,分别进行了对密度、酸度、新鲜度、掺碱、掺淀粉的测定。结果表明：民和县的生鲜乳仍存在酸度过高,新鲜度不够,掺假等的现象。     

酒精阳性乳的防制措施

酒精阳性乳是指在20℃左右的温度下,用68%～70%酒精与等量的牛乳混合后发生细小颗粒或絮状凝块现象的乳。根据其酸度的差异可将酒精阳性乳分为高酸度酒精阳性乳和低酸度酒精阳性乳2种。高酸度酒精阳性乳是在挤乳过程中卫生不合格,乳糖被细菌分解成乳酸,乳酸过高呈酒精阳性反应的乳,加热凝固;低酸度酒精阳性乳是刚从乳房挤出来就呈酒精阳性反应的乳,加热不凝固。牛乳的酸度是衡量牛乳新鲜度的主要指标之一,酒精阳性乳列为二等乳或生化异常乳,为不合格乳,不能作为乳品加工。所以凡属酒精阳性的乳都按不合格处理,致使不少牛乳被废弃或用于饲喂…     

散养户奶牛低酸度酒精阳性乳症的发生原因及防治对策

低酸度酒精阳性乳是指酸度在11～18°T，与同体积68％～70％的酒精反应后呈颗粒状浑浊或絮状沉淀的新鲜牛乳。低酸度酒精阳性乳与正常牛乳相比，钙、氯、镁以及乳酸含量高，尤其以钙含量增高，钠含量较少为特征。低酸度酒精阳性乳蛋白质、脂肪、乳糖含量与正常牛乳相比几乎没有差别，但蛋白质成分变异大，尤其是酪蛋白含量显著增高，蛋白质不稳定，从而导致酒精试验稳定性降低。     

猪肉新鲜度与微生物学指标的相关性研究

对不同鲜度４６份猪肉样进行了新鲜度与微生物学指标测定的平行对比试验。结果表明，猪肉的微生学指标与新鲜度变化密切相关。     

“抗乳凝”治疗奶牛低酸度酒精阳性乳的试验

“抗乳凝”治疗奶牛低酸度酒精阳性乳的试验仇晓林（黑龙江省虎林县农民中等专业学校，１５８４００）低酸度酒精阳性乳是指乳与７０％酒精等量混合，乳酸度低于１６度，发生絮状或凝块反应的乳。１９９０年以来，笔者实习期间筛选抗乳凝治疗低酸度酒精阳性乳２１例，均１...     

应用电导率测定猪肉新鲜度的试验研究

多年来,有许多从不同方面探索肉新鲜度检查方法的报道。目前,我国食品卫生标准中以感官检查和挥发性盐基总氮(TVBN)测定作为肉新鲜度指标。虽然TVBN测定是评定肉品质量(新鲜度)的重要客观指标,但由于TVBN测定操作较复杂,时间长,故不适于农贸市场等基层单位快速、简便判定肉新鲜度的需求。为此,我们应用电导仪进行了猪肉新鲜度的测定试验,现报道如下。     

浅析阳性乳

牛乳的酸度是衡量牛乳新鲜度的主要指标之一,阳性乳列为二等乳或生化异常乳,为不合格乳,不能作为乳品加工。所以凡属阳性的牛乳都按不合格处理,致使不少牛乳被废弃或用于饲喂犊牛,造成资源浪费。近年来,奶牛阳性乳的发生率较高,给奶牛养殖业及奶业生产造成极大的经济损失,因此,必须采取有效的防治措施。本文就是针对阳性乳的产生原因及防治措施进行分析与探讨。     

肉品中几个新鲜度指标的对比试验

随着人民生活水平的不断提高,人们对肉的卫生质量要求越来越高,而新鲜度是肉产品质量的最重要的指标之一,因而肉品新鲜度检验越来越引起人们的重视。本试验通过在同等实验条件下,对肉、脂肪中新鲜度测定的几个相关指标进行对比试验。     

Disease and destiny-mystery and mastery

When early people made their appearance, zoonotic infectious diseases were already waiting, but epidemic diseases did not appear in human history until people began to live in large numbers under conditions of close contact, mainly during the last 10,000 years. Disease has decimated urban populations, conquered armies, and disrupted society. The focus here is on (1) the plague of Athens and the Black Death; (2) smallpox, influenza, and rabies; (3) avian influenza prion diseases, and foot & mouth disease; and (4) emerging and re-emerging diseases. All have veterinary public health associations. In Athens, Greece, in 430 BC, when the Spartans ravaged the countryside, hordes crowded into Athens so that orderly movements, space in which to live, and adequate supplies of food became impossible. Crowding of any population fosters disease transmission; chaos and disorder enhance it all the more. Out of northern Egypt came a terrible plague from across the Mediterranean Sea. The identity of the plague of Athens remains unsure, but the well-considered conclusion is Rift Valley Fever, a mosquito borne, viral zoonosis. The Black Death, also called the Plague, raged in Asia for centuries. In 1347, the Black Death was brought by a ship out of Asia to Sicily. The scenes of devastation were repeated throughout Europe, with 90% or more of the people dying in city after city. Influenza, too, has been a cause of periodic human epidemics, but the great pandemic of influenza occurred in the last months of World War I. In the years of highest occurrence, more than half the world's population became clinically infected. If veterinary public health had been born earlier, it could have led to elucidating the epidemiology of influenza and the plagues of Athens, Europe, and Asia. In turn, smallpox had also caused continual tragedy. In 1796, Edward Jenner began to harvest pustules of cowpox from children or infected cows and inject them into susceptible children. In 1980, the World Health Organization declared that smallpox had been eliminated from the world. Rabies, though, still strikes terror. A number of animal diseases, broadly termed emerging and re-emerging diseases, need surveillance because they have the potential to impact human health. From late in 2003 to 2007, the highly pathogenic H5N1 influenza virus in poultry infected at least 121 people and caused 62 deaths in four countries. The prion diseases, too, all have very high numbers in concentrated contacts. To control these diseases, veterinary public health is essential, with diagnosis, epidemiological surveillance, clinical manifestations, and prevention as primary measures.     

Foot and mouth disease and bluetongue: differences and similarities

On 26th of july 2007 a new case of bluetongue was notified in the Netherlands and on 2nd of august 2007 foot-and-mouth disease was diagnosed in Surrey, England, which raised the threat of having both infections simultaniously in one area. Bluetongue and foot-and-mouth disease have a different pathogenesis, but symptoms may resemble each other at a later stage of infection. The pathogenesis and possible clinical symptoms of both infections are discussed and illustrated with pictures.     

奶牛肢蹄病及其防治

简介常见奶牛肢蹄病种类及其症状,从日粮营养、运动场地面结构、环境卫生、饲养管理、遗传育种、疾病管理等方面简析奶牛肢蹄病的病因,并提出相应的预防措施。     

德国荷兰畜禽产品质量安全交流与启示

2018年岁末,笔者有幸赴德国和荷兰,就畜产品质量安全控制及检测技术等进行了短期交流,收获颇丰,现具体介绍如下。一、交流情况德国面积35.73万平方千米,人口约8175.2万,是欧盟人口最多的国家,农业发达,机械化程度很高。德国的畜牧业以猪、牛、羊和禽类为主,畜牧业产值占农业生产总值的61%。德国虽然农业比重很小,但却是有机农业运动最早的发起国,也是目前世界上有机农产品生产与消费大国。     

畜禽物种多样性及其保护和利用

文章就我国畜禽物种多样性资源的现状、保护和利用等方面进行阐述,为生态脆弱的喀斯特地区畜牧业可持续发展提供参考。     

马的咽气癖及其防制措施研究进展

在动物的异常行为中以刻板行为最为常见,而咽气癖又是马最常见的口部刻板行为之一。作者就咽气癖在生理方面和心智方面对马体产生的影响、行为基础、诱因的研究进展及常见的防治措施进行综述。     

国内外蛋氨酸与赖氨酸市场分析与展望

近几年,世界饲用添加剂市场增长较快,预计今后将进一步增长,据世界粮农组织(FAO)首领会议的倡议,到2015年,将使世界营养不良的人口削减一半,其间,肉制品将会以每年2％的速度增长,特别是加快猪肉和禽肉增长。这将促进世界添加剂,尤其是蛋氨酸和赖氨酸需求量的增加。     

牛羊焦虫病诊断与防治技术

近几年来,辽宁省牛羊饲养业迅速发展,焦虫病的危害越来越明显,已成为危害牛羊的主要疾病之一。为了提高牛羊焦虫病的防治水平,保证我省牛羊饲养业的健康发展,笔者在参阅文献和同行们诊疗经验的基础上,结合自己的治疗实践,详细阐述了我省牛羊焦虫病近几年的流行特点和诊断防治方法。