What is artificial meat and what does it mean for the future of the meat industry?

The meat industry cannot respond to increases in demand by ever increasing resource use. The industry must find solutions to issues regarding animal welfare, health and sustainability and will have to do so in the face of competition from emerging non-traditional meat and protein products in an increasingly complex regulatory environment. These novel meat and protein products, otherwise known as ‘artificial meat' are utilising ground breaking technologies designed to meet the issues facing the conventional meat industry. These artificial meats, in vitro or cultured meat and meat from genetically modified organisms have no real capacity to compete with conventional meat production in the present environment. However, meat replacements manufactured from plant proteins and mycoproteins are currently the biggest competitors and are gaining a small percentage of the market. Manufactured meats may push conventional meat into the premium end of the market, and supply the bulk, cheap end of the market if conventional meat products become more expensive and the palatability and versatility of manufactured meats improve. In time the technology for other artificial meats such as meat from genetic modified organisms or cultured meat may become sufficiently developed for these products to enter the market with no complexity of the competition between meat products. Conventional meat producers can assimilate agroecology ecology concepts in order to develop sustainable animal production systems. The conventional meat industry can also benefit from assimilating biotechnologies such as cloning and genetic modification technologies, using the technology to adapt to the changing environment and respond to the increasing competition from artificial meats. Although it will depend at least partly on the evolution of conventional meat production, the future of artificial meat produced from stem cells appears uncertain at this time.     

Alternatives for large-scale production of cultured beef: A review

Cultured beef is a method where stem cells from skeletal muscle of cows are cultured in vitro to gain edible muscle tissue. For large-scale production of cultured beef, the culture technique needs to become more efficient than today's 2-dimensional(2D) standard technique that was used to make the first cultured hamburger. Options for efficient large-scale production of stem cells are to culture cells on microcarriers, either in suspension or in a packed bed bioreactor, or to culture aggregated cells in suspension. We discuss the pros and cons of these systems as well as the possibilities to use the systems for tissue culture. Either of the production systems needs to be optimized to achieve an efficient production of cultured beef. It is anticipated that the optimization of large-scale cell culture as performed for other stem cells can be translated into successful protocols for bovine satellite cells resulting in resource and cost efficient cultured beef.     

猪肌肉干细胞在三维水凝胶中的分化研究

【目的】 探究猪肌肉干细胞在三维水凝胶中的分化效果,为体外诱导肌肉干细胞分化成为肌肉组织提供方法指导。【方法】 将一定数目的猪肌肉干细胞分别在二维和三维条件下诱导分化（二维条件指在培养皿中培养细胞,三维条件指在水凝胶中培养细胞）,分别收取增殖阶段、预分化阶段、分化初期、分化成熟、分化末期的二维培养细胞的RNA和蛋白样品,以及分化7和14 d的三维培养细胞的RNA和蛋白样品。利用RT-qPCR技术检测细胞在两种条件下分化至不同阶段时成肌相关基因MYOG、CAV-3、MyHC-slow、MyHC-2a的表达水平;利用Western Blot技术检测细胞在两种条件下分化至不同阶段时MYOG、MyHC蛋白的表达水平;利用免疫荧光染色技术观察猪肌肉干细胞在二维和三维条件下融合形成的肌管;使用氨基酸自动分析仪检测分化14 d培养肌肉组织的氨基酸含量及组成。【结果】 二维培养的猪肌肉干细胞在分化第3天时开始发生肌融合,在分化第7天形成成熟肌管,随后进入分化末期,肌管开始脱落。三维培养的猪肌肉干细胞在分化第7天时还未完全伸展,细胞的MYOG和CAV-3表达水平低;分化第14天时水凝胶内已形成多核肌管,MYOG和CAV-3表达达到二维分化水平。三维分化有利于终末分化基因MyHC-slow和MyHC-2a的表达,分化14 d时MyHC-slow的表达量是二维分化7 d的12倍,MyHC-2a的表达量是二维分化7 d的4倍,但是MyHC蛋白的表达量仅为二维分化7 d时的1/6。氨基酸分析结果表明体外培养肌肉组织中17种水解氨基酸含量均低于猪肉,且必需氨基酸在总氨基酸的占比也低于猪肉,但是呈味氨基酸的占比相较猪肉更高。【结论】 猪肌肉干细胞可以在三维胶原水凝胶中分化形成肌管,且三维条件有利于成肌分化相关基因表达,但要实现MyHC蛋白的高表达还需进一步研究,按此方法体外培养的肌肉组织有较高的呈味氨基酸含量,可能会有较好的风味。     

Artificial meat? Feasible approach based on the experience from cell culture studies

This short review is to list pros and cons which are based on the literature and personal experience in cell culture studies related to possible commercial production of artificial meat as functional food. The general view of muscle composition and determinants of meat quality are shortly described. Principles of muscle cell propagation in culture and mutual relationships between different cell types present in this organ are briefly discussed. Additionally, the effects of some cytokines and growth factors for muscle cell growth and muscle tissue development are indicated. Finally, conclusion remarks related to detrimental consequences of meat production to natural environment as well as personal opinion of author on the prospects of artificial meat production are declared.     

精原干细胞体外分离培养的研究进展

为探索提高精原干细胞分离和体外培养效率的技术方法,以建立长期稳定的动物精原干细胞培养体系,对动物精原干细胞的分离纯化和体外培养的研究进展进行综述。以"Spermatogonial stem cell,Isolation,Culture,Enrichment,in vitro"和"精原干细胞、分离、培养和体外扩增"为检索词,查阅精原干细胞相关文献,并进行归纳整理。精原干细胞分离主要有机械分离法和酶消化法,纯化精原干细胞的方法有差速贴壁法、密度梯度离心法、免疫磁珠法、流式细胞法等,目前大动物精原干细胞的富集常使用酶消化法、差速贴壁法和Percoll梯度离心法相结合。精原干细胞体外培养需模拟体内生境,通常在基础培养基中添加血清、饲养层细胞和各类生长因子等,培养条件会影响精原干细胞培养的效果。小鼠精原干细胞已建立较完善的培养体系,而人和多数大动物还缺乏完善的精原干细胞体外培养体系。     

Cultured meat in western media: The disproportionate coverage of vegetarian reactions,demographic realities,and implications for cultured meat marketing

This paper examines the media coverage of the 2013 London cultured meat tasting event, particularly in the United States, Canada, and the United Kingdom. Using major news outlets, prominent magazines covering food and science issues, and advocacy websites concerning meat consumption, the paper characterizes the overall emphases of the coverage, the tenor of the coverage, and compares the media portrayal of the important issues to the demographic and psychological realities of the actual consumer market into which cultured meat will compete. In particular, the paper argues that Western media gives a distorted picture of what obstacles are in the path of cultured meat acceptance, especially by overemphasizing and overrepresenting the importance of the reception of cultured meat among vegetarians. Promoters of cultured meat should recognize the skewed impression that this media coverage provides and pay attention to the demographic data that suggests strict vegetarians are a demographically negligible group. Resources for promoting cultured meat should focus on the empirical demographics of the consumer market and the empirical psychology of mainstream consumers.     

Research on Isolation and Clone of Embryonic Stem Cell-Like in Bovine

Bovine embryonic stem cell would be invaluable for researching the aspect of animal cloning, production transgenic animal and discussion of gene function in vitro. With the object of establishing an effective culture system for isolation and clone of bovine pluripotent stem cell, we cultured bovine embryos and mouse embryos including morula blastula and hatached blastula and obtained animal ICM on Primary marine embryonic fibroblast (Primary murine embryonic fibroblast, PMEF) feeder layer with tissue medium(DMEM supplemented with 15ml/100ml NBS ,0.1μmol/L Na2SeO3, 0. 1mmol/L β-mercaptoethanol, 1 000ng/ml LIF,10 ng/ml IGF, 1mmol/L necessary amino acid and 1mmol/L L-glutamine), then, we obtained mouse ICM and bovine ICM. Moreover, we isolated and cloned the 6 passage bovine ES like cells(12 cell lines) and 9 passage marine ES like cells (52 cell lines) deriving from bovine ICM and murine ICM respectively on the feeder layer of PMEF by disaggregating ICM and ES cell clones of bovine and murine into smaller clumps through digesting with 0. 125g/100ml trypsin and 0.02g/100ml EDTA and scattering with a glass needle. The pluripotency of both murine and bovine ES like cells was identified with morphological character, histochemistry identification, karyotype analysis and differentiation of ES cells in vitro or in vivo. This result showed that bovine embryonic stem cell and murine embryonic stem cell had developmental pluripotency.     

胚胎干细胞诱导分化研究进展

哺乳动物胚胎干细胞一般可从胚胎囊胚内细胞团分离得到 ,具有在体外保持不分化的无限增殖能力 ,在合适的培养条件下 ,胚胎干细胞可定向诱导分化形成多种细胞类型。人们对胚胎干细胞进行体外培养与定向分化可以得到大量同源细胞 ,以应用于患疾病的细胞或器官移植治疗等研究。文章概述了胚胎干细胞增殖与分化的信号调节机制、诱导分化方法 ,国内外研究概况及展望 4个方面的内容     

羔羊育肥技术

羔羊肉具有瘦肉多、脂肪少、味美鲜嫩、容易消化等特点;育肥羔羊具有增重快、饲料报酬高、产品成本低、生产周期短、经济效益高等特点.因此,世界上养羊业发达国家都把肥羔生产作为羊肉生产的重点.介绍了国内外肉羊业的发展现状、趋势,国外先进的肥羔生产技术,羔羊育肥的技术要点;期望对我国的羊肉生产和羊肉品质的提高有所帮助.     

关中奶山羊羯羔肉用性能的初步研究

选用18只肥育后健康羯山羊,屠宰后系统测定了有关肉用性能和肉质特性指标。并用多元统计方法对指标间的相互关系作了详尽地分析。结果表明,不同体重间屠宰及胴体性状差异显著,山羊肉中胆固醇含量显著低于其他肉类,肌肉、肾脂的脂肪酸组织差异十分明显,活重与胴体重相关系数高达0.97,活体指标与胴体指标间典型相关系数也达0.96。本研究首次测定了肌肉中乳酸脱氢酶和肌酸磷酸激酶的活性。为肉质特性研究提供了参考。     

Histological Study on in vitro Co-cultivation of the Myocardium Tissue and Cells with Mouse Embryonic Fibroblasts

The histological observation was experimentally conducted on in vitro cultured mouse embryonic myocardium cells and myocardiumoid cell mass. The mouse embryo tissue were cultured and regular pulsatile myocardiumoid tissue could be found. During in vitro culture, the myofllament bundles in the cell were gradually increasing andstrongly connectted each other with embryonic age and there were loose muscle fibers initially and intercalated discs were close to each other. The lose myofllament bundles were developed in muscle fibers with age and the distance between intercalated discs was enlarged. There were myofilamentoid structure in inactive cells and filament peripherily.     

大鼠骨骼肌卫星细胞培养的研究

[目的]探讨在体外条件下骨骼肌卫星细胞纯化、培养、鉴定的方法及确定其生物学特性。[方法]取新生大鼠的小腿肌肉,采用肌组织块和肌细胞培养两种方法。分别用胰蛋白酶对培养中的肌组织块和肌细胞进行消化,采用离心及差速贴壁法纯化,得到更高纯度的大鼠骨骼肌肌卫星细胞,进行体外原代骨骼肌和传代骨骼肌的细胞培养。传至第2代后,用分化培养基诱导分化,观察骨骼肌细胞各个阶段的形态特征并拍照。[结果]此方法分离的细胞成活率较高,体外生长、增殖良好。在分化培养基条件下,细胞分化良好,可融合成肌管。[结论]该实验成功探讨了新生大鼠骨骼肌卫星细胞的分化能力并建立了卫星细胞纯化方法,适用于开展细胞移植和肌组织工程方面的研究。     

山羊胎儿肌肉干细胞的分离培养与成肌诱导分化

【目的】通过体外建立安淮山羊胎儿肌肉干细胞分离培养及成肌诱导分化的方法,为进一步研究调控山羊肌肉干细胞增殖与分化的分子机制提供实验材料。【方法】本试验选取山羊胎儿背最长肌肌肉组织,用眼科剪剪成肉糜后,用0.1%的Ⅰ型胶原酶消化40 min,然后利用0.25%的胰酶消化15 min。分离得到的细胞用生长培养基（20%FBS+80%DMEM/F12+青链霉素）培养于37℃、5% CO2培养箱内。培养2h后采用差速贴壁技术对细胞进行纯化,又2h后,重复纯化一次。待细胞生长至70%左右密度时可进行传代培养。每次传代培养均采用差速贴壁30min的方法进一步纯化肌肉干细胞,共纯化至第6代。利用免疫荧光技术检测第6代细胞中肌肉干细胞标记基因Pax7、MyoD1的蛋白表达情况,从而对分离得到的细胞进行鉴定。当肌肉干细胞生长至70%左右密度时,将生长培养基更换为分化培养基（2%FBS+98%DMEM/F12+青链霉素）,诱导细胞向成肌方向分化并观察细胞的形态学变化。细胞诱导分化1d后,采用免疫荧光技术检测肌肉干细胞的分化标记基因Myog的蛋白表达情况。另外,分别提取诱导0、1、3、5、7d后的细胞的总RNA,通过反转录试剂盒反转成cDNA后,利用qPCR测定MyoD1和Myog的相对表达量。【结果】 分离得到的细胞呈贴壁生长,其形态趋于稳定后主要呈长梭形或纺锤形。免疫荧光技术检测的第6代细胞中Pax7和MyoD1蛋白均为阳性表达。采用分化培养基诱导细胞分化后,在显微镜下可观察到随着诱导天数的增加,细胞开始分化、相互融合成肌管且具有一定的方向性。免疫荧光检测结果表明Myog蛋白呈明显的阳性表达。另外,qPCR结果显示,标志基因MyoD1和Myog均有表达,且MyoD1的相对表达量在分化的第1天相比于0天显著升高并维持到第3天,第5、7天开始显著下降但仍显著高于增殖期。Myog在分化不同天数的细胞中的相对表达量具有类似的趋向。【结论】分离得到了纯度较高的安淮山羊胎儿肌肉干细胞,且诱导后展现出较好的成肌潜力。研究结果可为进一步开展肌肉干细胞成肌分化的分子机制研究提供材料来源。     

有机肉类研究动态

有机农业对农副产品的生产加工和销售是一个正在兴起的领域，在全球范围内得到了广泛的关注．发达国家在有机肉方面已经取得了突破性的进展，但在发展中国家，特别是亚洲国家还只处于构想阶段，少数亚洲国家已经开始有机畜产品的开发．本文概述了有机肉产品的发展情况，并对其未来发展趋势做出预测．     

Educated consumers don't believe artificial meat is the solution to the problems with the meat industry

The production of in vitro meat by cell culture has been suggested by some scientists as one solution to address the major challenges facing our society. Firstly, consumers would like the meat industry to reduce potential discomfort of animals on modern farms, or even to avoid killing animals to eat them. Secondly, citizens would like meat producers to reduce potential environmental deterioration by livestock and finally, there is a need to reduce world hunger by increasing protein resources while the global population is predicted to grow rapidly. According to its promoters, artificial meat has a potential to make eating animals unnecessary, to reduce carbon footprint of meat production and to satisfy all the nutritional needs and desires of consumers and citizens. To check these assumptions, a total of 817 educated people(mainly scientists and students) were interviewed worldwide by internet in addition to 865 French educated people. We also interviewed 208 persons(mainly scientists) after an oral presentation regarding artificial meat. Results of the three surveys were similar, but differed between males and females. More than half of the respondents believed that "artificial meat" was feasible and realistic. However, there was no majority to think that artificial meat will be healthy and tasty, except respondents who were in favour of artificial meat. A large majority of the respondents believed that the meat industry is facing important problems related to the protection of the environment, animal welfare or inefficient meat production to feed humanity. However, respondents did not believe that artificial meat will be the solution to solve the mentioned problems with the meat industry, especially respondents who were against artificial meat. The vast majority of consumers wished to continue to eat meat even they would accept to consume less meat in a context of increasing food needs. Only a minority of respondents(from 5 to 11%) would recommend or accept to eat in vitro meat instead of meat produced from farm animals. Despite these limitations, 38 to 47% of the respondents would continue to support research on artificial meat, but a majority of them believed that artificial meat will not be accepted by consumers in the future, except for respondents who were in favour of artificial meat. We speculated that the apparent contradictory answers to this survey expressed the fact that people trust scientists whoare supposed to continuously discover new technologies potentially useful in a long term future for the human beings, but people also expressed concern for their health and were not convinced that artificial meat will be tasty, safe and healthy enough to be accepted by consumers.     

酶联免疫法检测盐酸克伦特罗的试验报告

盐酸克伦特罗酶联免疫反应测试盒适用于尿样、组织和饲料等样品中克伦特罗残留的定量检测。克伦特罗作为一种主要的β-兴奋剂应用于畜禽肉制品生产中,用以提高肌肉和脂肪的比例并加快生长速度。由于克伦特罗可作为肌肉舒缓剂用于人类疾病治疗,在畜禽中过量残留可能会对消费者造成危害,为此,被禁止在食品生产中应用。根据美国FDA和WHO规定,在肌肉和脂肪中克伦特罗的含量不能超过0.2ng/g,在肝脏和肾脏中其含量不能超过0.6ng/g。与传统的HPLC或GC-MS方法相比,酶联免疫方法具有操作简便、灵敏度高、成本低的优点。盐酸克伦特罗酶朕免疫反应测试盒为养殖者和政府监督管理部门提供了更准确快速检测克伦特罗残留的方法,该试剂盒的特点包括4方面,第一,该试剂盒的提取方法能达到75%～95%以上的回收率,可以不需用有机溶剂并在10～30min之内完成提取过程。第二,高灵敏度(0.05ng/g);低检测下限(肉类/脂肪0.025ng/g,尿液0.05ng/ml,饲料0.2μg/kg)。第三,检测过程只需不到2h。第四,高重复性。     

骨骼肌肌纤维形成机制的研究进展

骨骼肌是动物躯体最重要的组成部分,占到产肉动物躯体的40%,肌纤维作为骨骼肌组织的主要成分,其类型的差异是影响产肉动物肌肉品质的重要因素之一。因此,骨骼肌的生长发育与产肉动物肉的产量有着密切的联系,而其生理生化特性的差异也将会直接影响到产肉动物屠宰之后肉品的质量。一般而言,动物骨骼肌肌纤维数目在胚胎发育期间基本上就已固定,出生之后,由于肌纤维的肥大,动物躯体肌肉块才表现出增大增粗。另外,动物肌肉块在生长发育过程中,其肌纤维组成类型并不是完全固定的,它们会随着骨骼肌对代谢与功能需求的改变而发生转变。骨骼肌的生长发育,以及骨骼肌肌纤维类型的发生与发展是一个非常复杂的生物学过程,受到许多信号通路与因子的调控。随着分子生物学技术的飞速发展,各种先进技术相继被应用于生物学现象的研究中,利用这些分子生物学技术很好的阐明了许多复杂生物学现象形成的分子机制。目前,骨骼肌生长发育的分子遗传调控机制取得了长足的进展,许多与骨骼肌形成发育相关的关键因子已被鉴定出来。然而,在早期研究中,人们对于骨骼肌肌纤维的研究主要集中在类型的鉴定,以及不同肌纤维类型生理生化特性的分析,对于骨骼肌肌纤维形成的具体分子遗传调控机制的研究相对较少。近年来,随着研究的不断深入,骨骼肌肌纤维形成的分子遗传调控机制也取得了突破性的进展。因此,有必要进一步对骨骼肌肌纤维类型的特性,骨骼肌肌纤维类型形成的分子机制,以及肌纤维类型与肌肉品质的关系进行全面的综述。本文首先对肌纤维的类型、特性进行了综述;进一步分别对慢型肌纤维与快型肌纤维形成的分子调控机制的研究进展进行了回顾;最后对肌纤维类型与肉品质的关系进行了讨论。总之,本综述的撰写将有助于对骨骼肌肌纤维类型形成的遗传机制的进一步了解,为将来进一步的深入研究肌纤维形成的分子机制提供参考;同时也将有助于揭示肌肉品质形成的分子遗传调控机制,为利用分子生物学技术培育高品质新品种或新品系产肉动物提供分子理论依据。     

多酚-肌原纤维蛋白互作对蛋白的影响

肌原纤维蛋白是组成肌肉纤维蛋白的其中一种,肌原纤维蛋白的空间结构,蛋白的氧化性、凝胶性、乳化性等功能特性对肉制品的品质有十分重要的影响。在日常生活中,蛋白质氧化是一种常见的现象,这一现象以前没有得到很好的认识,很大程度上被忽视但现在更好了,据了解,这是一个复杂的化学过程,比如我们经常在生活中发现肉储存久了,颜色会由鲜红色变成棕褐色,这就是蛋白质氧化的导致的。所以,在肉制品中加入合适的抗氧化剂来防止肉制品的氧化变质是非常重要的,也是现在科研正在积极探索的方向。据对食品蛋白质氧化的研究发现,茶多酚它具有极强的清除有害自由基的能力,可以有效的防止肉制品的颜色发生变化,延长了肉制品的保质期,故茶多酚是目前发现的一种可理想的运用在肉制品的天然抗氧化剂之一。这篇文章综述了近些年来国内外关于茶多酚与蛋白的相互作用方式,研究了茶多酚与肌原纤维蛋白相互作用的作用机理,及在肉制品中加入多酚后,多酚与肌原纤维蛋白形互作对蛋白质性能的影响。     

动物硒蛋白功能、表达及其肉质调控机制研究进展

硒蛋白是微量元素硒(Se)在动物体内发挥生物学功能的主要形式,其表达调控与动物生长和畜禽肉质密切相关。介绍动物体内Se元素吸收代谢的过程及其主要存在形式,系统总结动物硒蛋白的结构、种类、表达分布、生物学功能、合成过程、影响因素与候选功能基因等,重点分析硒蛋白在活体肌肉中的作用,以及对畜禽肉质调控的影响。通过梳理上述方面的研究进展,以期为新饲料添加剂开发和畜禽肉质调控研究提供科学依据。     

青海大通犊牦牛肉与成年牦牛肉品质的比较

用常规方法测定了青海大通犊牦牛肉和成年牦牛肉的产肉性能和食用品质,并研究了犊牦牛肉与成年牦牛肉在成熟过程中肌原纤维超微结构的变化.结果表明:犊牦牛肉的系水力、pH值均高于成年牦牛肉,并且失水率、熟肉率、剪切力均低于成年牦牛肉,说明青海大通犊牛肉比成年牦牛肉食用品质高;在成熟过程中,青海大通犊牦牛肉与成年牦牛肉肌原纤维发生不同程度的轻微断裂,Z线断裂,犊牦牛肉肌原纤维间的横桥交联断裂,结构模糊,说明犊牦牛肉降解效果更加明显.