水溶性大豆多糖和果胶作为酸性乳饮料稳定剂的研究

通过改变酸性乳饮料的加工工艺比较了大豆多糖和果胶在稳定酸性乳饮料时的差异.结果表明,温度和调酸的顺序对添加了大豆多糖的酸性乳饮料稳定性的影响比对添加了果胶的酸性乳饮料稳定性的影响更为显著.在0℃时调酸和调酸之后均质的条件下,添加有0.40%大豆多糖的酸性乳饮料的稳定性最好,沉淀率最低为0.69%;而添加有0.35%果胶的酸性乳饮料的沉淀率为0.71%.而且进一步验证了大豆多糖能在pH值为3.4～4.4范围内稳定酸性乳饮料,而果胶只能在pH值为3.6～4.4范围内稳定酸性乳饮料.     

果胶和可溶性大豆多糖在酸性乳饮料中的应用

通过优化工艺条件,提高果胶复配可溶性大豆多糖在酸性乳饮料的稳定性.以Turbiscan和Lumisizer稳定性扫描结果、粒径分布为指标,通过正交设计实验,结合产品离心沉淀率来确定果胶复配可溶性大豆多糖和酪蛋白最适作用浓度、最适作用pH值和调酸前后均质工艺、复配胶体添加顺序对产品稳定性影响.结果表明,影响产品离心沉淀率...     

大豆多糖在调配型酸性乳饮料中的应用

通过改变调配型酸性乳饮料的调酸工艺之及调酸以后的处理,确定了大豆多糖SSPS(soluble soybean polysaccharide)作为稳定剂的最佳工艺参数。结果表明,蛋白质含量为1.5%的脱脂酸性乳饮料在SSPS添加量为0.6%,5℃调酸,搅拌速度为1000r/min,均质压力为30MPa下,SSPS对酸性乳饮料的稳定性最好,沉淀率最低。     

羧甲基纤维素钠及酸性乳饮料加工工艺对其稳定性及粒径分布的影响

研究了羧甲基纤维素钠（CMC）及酸性乳饮料加工工艺对其稳定性及粒径分布的影响。通过离心沉淀法检测酸性乳饮料的稳定性．对影响稳定效果的主要加工工艺进行了试验。同时测定了这些加工工艺对产品粒径分布的影响,并分析了体系粒径分布与产品稳定性之间的关系。结果表明,CMC添加量、pH值、均质压力、调酸温度等因素都会影响酸性乳饮料的稳定性和粒径分布,其中CMC添加量和均质压力对结果影响明显,调酸温度次之,pH值对结果影响最小。     

果胶对酸性乳饮料稳定性的影响

酸性乳饮料的稳定性与稳定剂的含量、均质压力、均质温度、pH有关。选取果胶作为稳定剂,探讨了工艺条件对酸性乳饮料稳定性的影响。结果表明：果胶添加量0.4%、均质压力20MPa、均质温度50℃、pH4.3时酸性乳饮料的稳定性最好。     

可溶性大豆多糖对于配制型酸性乳饮料稳定效应影响因素研究

利用离心沉淀率、粒径、LUMisizer稳定性分析仪研究了可溶性大豆多糖(Soluble soybean polysaccharides,SSPS)添加量、乳饮料中蛋白质含量、SSPS和果胶复配比例对配制型酸性乳饮料稳定性的影响。结果表明,随着SSPS添加量的增大,配制型酸性乳饮料的离心沉淀率和平均粒径均逐渐减小,LUMisizer稳定性逐渐增强,0.4%的SSPS添加量对于含蛋白量1.0%的酸乳体系稳定效果最好;随着蛋白质含量的增加,饮料稳定性逐渐变差,0.4%的SSPS只能稳定蛋白质含量不超过2.0%的乳饮料;SSPS与果胶在酸性乳饮料中可起到协同增强稳定性的作用,当体系中添加0.1%的SSPS和0.3%的果胶时,酸乳体系稳定性最好。     

变性淀粉对酸性乳饮料稠度和稳定性的影响

探讨变性淀粉对酸性乳饮料中起增稠作用的最适添加量以及对产品黏度以及稳定性的影响。通过不同来源、不同添加量及不同杀菌工艺对比实验,以产品黏度、Lumi稳定性分析图谱以及产品观察指标为评价标准,得出变性淀粉在酸性乳饮料中起增稠作用最适添加量以及工艺指标对产品黏度影响规律。结果表明:在酸性乳饮料中添加变性淀粉能够显著提高产品黏度,并且变性淀粉在一定程度上可以改善产品观察期内稳定性;杀菌工艺影响产品黏度,巴氏杀菌工艺黏度高于UHT(超高温瞬时灭菌)杀菌工艺,在UHT工艺中,随杀菌温度的升高,产品黏度会有一定程度的降低;不同的均质温度对产品黏度无太大影响;不同厂家变性淀粉对产品稳定性有一定影响。结论:耐剪切变性淀粉在乳饮料中增稠的最适添加量为1.5%,生产厂家可以根据不同黏度需求采用不同杀菌工艺,巴氏杀菌工艺、UHT(超高温瞬时杀菌),同时应考虑不同厂家淀粉带来的产品品质差异。     

大豆水溶性多糖对酸性乳饮料稳定作用的研究

通过测定添加不同质量分数的大豆水溶性多糖对酸性乳饮料的沉淀率、黏度、粒径分布、水分子流动性及Zeta电位的影响,研究了大豆水溶性多糖对酸性乳饮料的稳定作用.结果表明,大豆水溶性多糖对酸性乳饮料的稳定作用表现为使产品的沉淀率降低,黏度升高,在微观性质上表现为使产品的粒径减小,水分流动性减弱,Zeta电位的绝对值升高.其中大豆水溶性多糖对产品的粒径分布有较大影响,对产品的Zeta电位和水分子的流动性影响较小.     

香蕉乳饮料稳定性研究及工艺条件优化

本文以快速稳定性分析仪Turbiscan Tower得到的稳定性动力学指数系数TSI为评价指标,通过单因素及正交试验设计研究了稳定剂添加量、均质压力、均质温度对香蕉乳饮料稳定性的影响,得到稳定性较优的工艺参数。结果表明,稳定剂添加量和均质压力对香蕉乳饮料稳定性的影响较显著,均质温度影响相对较小;产品在稳定剂添加量为3.5 g/L、均质压力26 MPa、均质温度为65 ℃时,稳定性最好,TSI值为0.22。     

调酸型调制乳的研制

以生牛乳、水、白砂糖、乳酸、柠檬酸为原料,采用配料、调酸、均质和UHT杀菌制成调酸型调制乳。利用保温加速试验和感官评定正交试验研究产品配方和工艺。结果表明,最佳配方为:生牛乳80%、白砂糖7%、柠檬酸0.12%、乳酸0.6%、羧甲基纤维素钠0.12%、果胶0.24%、大豆多糖0.24%。最佳调酸温度为20℃,最佳调酸速率为1 000 L/h,调酸后需要增加冷均质(15 MPa, 20℃)。产品口感爽滑,酸甜适中,组织状态均一稳定。终产品理化指标为脂肪2.5%、蛋白质2.3%、p H 4.2。     

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