牦牛初乳及其过渡乳中维生素变化规律的研究

以牦牛分娩后7d内初乳及过渡乳为研究对象,利用高效液相色谱法分析了不同泌乳时期其维生素A、维生素E及B族维生素的含量变化规律。结果表明,牦牛初乳中VA、VE、VB1、VB2和VB3在分娩后第1d含量最高,分别为367.76、780.11、93.41、367.76、98.93μg/100g,之后随分娩后泌乳天数的增加急剧下降(p<0.05),3d后下降速度趋于平缓;VB5在分娩后第1d含量最低,为201.49μg/100g,3d内含量急剧上升(p<0.05),随后速度趋于平缓;VB6和VB11不受泌乳天数的影响;初胎牦牛初乳及过渡乳中VA、VE、VB1含量高于经胎;其他维生素含量不受胎次影响。本文为合理开发利用牦牛乳资源提供理论依据。     

舍饲新疆褐牛初乳产量及乳成分测定

测定10头全舍饲新疆褐牛母牛分娩后2，24，48，72，96，120h的初乳产量、常规营养成分、IgG和矿物元素含量。结果表明，母牛分娩后2h(第1次)所挤初乳产量平均为4.73kg，72h内初乳平均总产量为46．6kg，占成母牛305d平均产奶量的0．9％；120h内初乳平均总产量为85．1kg，占305d平均产奶量的1．65％。2h挤出的初乳其蛋白质、脂肪、乳糖、灰分的含量分别为12．59，6．5，2．87，1．11g／100g，是常乳的3．93，1．76，0．57，1．48倍；IgG质量浓度为60．56g／L，是常乳的108．14倍；Ca，P，Na，Mg，Fe，Zn的含量分别为186．03，167．10，89．65，23.31，0．30，2．25mg／100g，是常乳的1．66，2．01，1．81，2．05，2．14，6．43倍。随泌乳期的延长，初乳中除乳糖以外的各种成份均迅速下降，在48h以内，以蛋白质和IgG的下降幅度最大，分别达62.27％和93．40％。至第120h，除蛋白质及矿物元素的Zn以外，各种成分已和常乳相接近。新疆褐牛分娩后不同时间段初乳成分的变化规律和荷斯坦牛相似。     

河南奶山羊及其杂种羊泌乳早期乳成分动态变化

对河南奶山羊及其杂种羊泌乳早期初乳及常乳主要常规成分进行分析。结果表明:奶山羊和杂种羊乳中干物质含量分别在泌乳的第1天和第2天最高,分别达24.14g/100g和26.17g/100g,高峰后随着泌乳期的延长总体上呈下降趋势;乳糖含量在两组羊乳中随着泌乳期的延长总体上均呈上升趋势;乳脂率均在泌乳第5天和第4天时最高,分别达6.32g/100g和5.38g/100g,随着泌乳期的延长呈下降趋势。奶山羊前5d含量所泌初乳中,乳蛋白含量逐渐升高,常乳中乳蛋白含量基本稳定,杂种羊乳蛋白含量在初乳期随着泌乳期的延长呈下降趋势,常乳中含量基本稳定。乳中的灰分含量随着泌乳期的延长总体呈下降趋势,到常乳期有波动。乳中钙含量在实验期趋于稳定,磷含量在初乳期随泌乳期延长而稍有增加,常乳期平稳下降。河南奶山羊及其杂种羊乳中主要成分随着泌乳时间的变化而变化,各主要成分含量的变化与饲养管理条件和羊只营养状况等因素存在密切关系。     

双峰驼乳功能蛋白及脂肪酸在泌乳期内的变化研究

为探究泌乳双峰骆驼乳功能性蛋白及脂肪酸变化规律,该研究动态追踪20峰泌乳双峰驼并采集泌乳期330 d内的驼乳,基于超高效液相色谱和气相色谱分析,检测α-乳白蛋白(α-lactalbumin, α-LA)、乳铁蛋白(lactoferrin, LF)、免疫球蛋白(immunoglobulin G, IgG)和溶菌酶4种目标功能蛋白及34种脂肪酸含量变化情况。结果表明,驼乳中共检测到4种目的功能蛋白及32种脂肪酸,色谱峰形尖锐、无杂峰干扰。驼乳4种功能蛋白含量在初乳期极显著高于常乳期(P<0.01),泌乳后期随着泌乳时间延长含量缓慢降低,功能蛋白间具有显著正相关性(P<0.05),其中α-乳白蛋白与IgG具有强正相关。脂肪酸含量在初乳期至常乳期30 d内波动明显,其余时期脂肪酸含量变化不大。长链脂肪酸、多不饱和脂肪酸和中链脂肪酸在泌乳期含量较为稳定;饱和脂肪酸和不饱和脂肪酸的比例合理,且饱和脂肪酸与不饱和脂肪酸及单不饱和脂肪酸变化趋势相反,在初乳期3～7 d内变化较为明显,在泌乳高峰期90～150 d波动极为明显,少数脂肪酸间具有较强的正相关。驼初乳功能蛋白与脂肪酸的组成及含量优...     

蒙古国戈壁红双峰驼乳化学组成及其动态变化

本实验对12峰戈壁红双峰驼驼乳的化学组成及其动态变化进行了研究。结果表明,第1次所挤初乳中总干物质为20.858%,在第2～30d间基本稳定在17.858～17.323%,第90d时降至14.488%。第1次所挤初乳中蛋白质含量为14.864%,24h后下降到8.153%,以后进一步缓慢下降。乳糖含量在泌乳第1～90d内变化较小,为4.353%～4.648%。第1次所挤初乳脂肪含量为0.278%,到24h增至4.259%,30d时为6.852%,90d又下降到5.705%。第1次所挤初乳中灰分含量为1.281%,到24h下降到0.918%,在90d泌乳期内稳定在0.861%～0.949%范围内。戈壁红驼产后第1次所挤的初乳中钙、磷含量最高,分别为216.059mg/100g和154.358mg/100g钙、磷、钠、钾及氯在2h～90d变化范围分别为156.323～216.059mg/100g、126.835～154.358mg/100g、60.067～83.025mg/100g、126.808～184.208mg/100g和85.600～193.200mg/100g;硫、镁、锌在2h～90d变化范围分别为37.108～43.208mg/100g、7.908～8.933mg/100g和0.628～0.652mg/100g。戈壁红驼90d内驼乳中VA、VC、VD、VE、VB1、VB2及VB6的平均含量分别为0.918mg/L、15.845mg/L、627IU/L、1.800mg/L、0.188mg/L、1.188mg/L和0.495mg/L。     

胎次及天数对牦牛初乳活性成分的影响

采用双抗体一步夹心法酶联免疫吸附实验(ELISA),研究了五个胎次的天祝白牦牛初乳中免疫球蛋白G(IgG)、乳铁蛋白(LF)以及胰岛素样生长因子-Ⅰ(IGF-Ⅰ)在产后七天的浓度变化规律,为探讨白牦牛初乳的营养价值及其资源的合理开发和利用提供理论依据.结果表明:天祝白牦牛初乳中IgG、LF和IGF-Ⅰ在分娩后第1天且四胎浓度最高,分别为2404.41、2001.53和1206.48U/L,其后都随产后泌乳天数的增加急剧下降,5天以后下降速度趋于平缓.产后四天内牛初乳的IgG、LF和IGF-Ⅰ含量仍可达较高水平,营养价值丰富,具有一定的开发价值,因此在开发利用牦牛初乳产品时,为扩大牛初乳的利用率,可采集四天内初乳进行加工利用.     

母乳与山羊乳功能性不饱和脂肪酸及脂肪球微观结构的比较

本研究采用气相色谱-质谱法及显微观察手段分析不同泌乳期母乳与山羊乳常乳中主要功能性不饱和脂肪酸相对含量、理化性质和微观结构,旨在为母乳脂质的研究及以山羊乳为基质的婴幼儿配方奶粉母乳化提供一定的数据支撑。结果表明：母乳初乳、过渡乳、成熟乳脂肪质量浓度显著增加（P＜0.05）,分别为（26.7±3.6）、（33.7±4.6）g/L和（41.0±6.8）g/L;山羊乳脂肪质量浓度（（42.1±4.3）g/L）显著高于母乳初乳和过渡乳（P＜0.05）。但母乳中主要功能性脂肪酸相对含量显著高于山羊乳,尤其是亚油酸相对含量（过渡乳中最低,为19.76%）显著高于山羊乳（4.43%）（P＜0.05）。在物理特性方面,母乳初乳脂肪球具有最大体积平均粒径（（5.63±0.51）μm）和最低ζ电位（（－5.72±0.21）mV）,而山羊乳脂肪球体积平均粒径和ζ电位分别为（3.63±0.31）μm、（－13.69±0.27）mV。脂肪球粒径、ζ电位与脂肪质量浓度显著相关（P＜0.05）。不同泌乳阶段母乳中主要功能性脂肪酸相对含量及脂肪球物理特性不同,与山羊乳差异明显。本实验结果可进一步用于母乳及山羊乳制品的研究。     

HPLC法检测牛初乳中IgG含量

建立了牛初乳中IgG的高效液相色谱检测法,并测定了初乳中IgG的经时变化过程.结果显示,IgG浓度在0.2～15mg/mL的范围内峰面积与浓度呈现良好的线性关系,回收率实验平均大于98.5%.采用本法测定了六头幽门螺杆菌免疫牛初乳中IgG及两头正常牛初乳中IgG的经时变化过程.母牛分娩后24h内,初乳中免疫球蛋白IgG平均含量在40～70mg/mL之间;3d后,初乳中免疫球蛋白总量下降较快;至第7d,初乳中免疫球蛋白含量平均在1～5mg/mL之间.     

双抗体夹心酶联免疫法测定水牛初乳中的IgG

为快速、准确地测定水牛初乳中IgG活性质量浓度,建立了双抗体夹心酶联免疫分析法(ELISA)。结果表明,IgG活性质量浓度的对数值与吸光值存在很好的线性关系,其标准曲线方程式为γ=-0.2907x2+2.0819x+0.8689,相关系数R2=0.9937,线性范围在7.8～1000ng/mL,平均回收率在84.40%～96.71%之间,灵敏度高、重现性好,可用于水牛初乳及其制品中IgG活性质量浓度的检测。     

高效液相色谱-三重四级杆质谱联用法检测荷斯坦和水牛原料乳中磺胺类药物残留

目的分析目前我国南方地区荷斯坦原料乳和水牛原料乳中磺胺类药物的残留情况。方法采集浙江和广西地区荷斯坦牛牧场和水牛牧场的120份原料乳,采用高效液相色谱-三重四级杆质谱联用法检测其中的磺胺类药物残留。结果方法的检出限和回收率分别为0.05~0.10μg/L和73.2%~108.3%。水牛乳中磺胺类药物的残留量低于6.67μg/L,荷斯坦牛乳中磺胺类药物的残留量低于7.88μg/L。结论高效液相色谱-三重四级杆质谱联用法检测牛乳中磺胺类药物残留的结果准确可靠,我国南方地区的荷斯坦原料乳和水牛原料乳总体上处于安全范围。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press