Saccharomyces cerevisiae SCY1发酵kefir的工艺研究

本文采用Saccharomyces cerevisiaeSCY1和乳酸菌混合发酵牛乳制备kefir,分别研究了接种量、灭菌条件、发酵温度和加糖量对kefir风味的影响,最终确定最佳工艺条件为:XPL-1接种量为0.0400g/L,SCY1接种量为103个/mL;灭菌条件为80~85℃下灭菌10min;发酵温度为32℃;加糖量为4%。通过此工艺条件制备的kefir,具有独特的风味和较高的营养价值。     

普洱茶饮料的研制

研究以普洱茶为主要原料制备茶饮料的工艺流程。通过实验确定最佳工艺参数为:浸提时间20min,茶水质量比1∶65,浸提温度85℃,浸提pH为5.0,离心速度7000r/min,灭菌温度135℃,5s瞬时灭菌。     

光致变色聚酯纤维的制备

为了制备一种使用寿命长、变色明显且成本低的光致变色材料,文章采用熔融纺丝的工艺,将自制的光致变色母粒与低熔点聚酯切片按比例混合制备出光致变色纤维,并对纺丝工艺与纤维性能进行研究。结果表明,一区温度185℃,二区温度200℃,三区温度210℃,四区温度215℃,五区温度215℃,机头温度215℃;转速为一辊234 m/min,二辊350 m/min,三辊690 m/min,卷绕速度693 m/min,满足以上条件时,丝束表现出良好的力学与变色性能。     

芦荟凝胶粉制备过程中大黄素变化研究

本文研究了芦荟凝胶冻干粉制备过程中芦荟大黄素在常温、40℃、85℃下,不同的漂烫时间过程中(0min、3min、6min)的变化,以及澄清剂处理对大黄素含量的影响。结果表明:大黄素含量随着漂烫时间和温度的增加而相应升高,其中漂烫时间对芦荟大黄素含量的影响更为显著,比较理想的制备工艺为温度为85℃,漂烫时间为6min;通过对芦荟大黄素硼砂体系扫描发现测定芦荟大黄素的最佳波长为445nm。     

基于计算流体动力学技术的橙汁高温短时灭菌工艺优化

为对果汁高温短时灭菌工艺进行精确研究,在确保果汁品质时降低生产中的能耗,对罐装橙汁的超高温短时灭菌进行计算,分析果汁中常见的细菌,得出灭菌所需的最低温度,在此基础上,利用计算流体动力学(CFD)技术对橙汁的高温短时灭菌方式进行模拟实验,探讨不同温度条件下的灭菌最理想时间条件。结果表明：120℃(393K)、12min,125℃(398K)、11min,130℃(403K)、8min,135℃(408K)、7min 为最理想时间条件;同时根据卡诺循环,计算高温短时灭菌的能耗,得到单位质量橙汁灭菌的机械耗功率分别为127、150、217、263W。根据能耗最低的原则可以得到计算的灭菌温度范围中,最优灭菌工艺为120℃(393K)、12min。     

酱大排杀菌条件及冷藏过程品质变化的研究

目的 研究酱大排的杀菌条件与冷藏过程中的品质变化, 解决酱大排保藏困难、容易变质的难题。方法 通过测定低温条件下的杀菌曲线及杀菌强度(F值), 研究不同杀菌条件对酱大排微生物、质构、色泽、感官的影响, 为酱大排选择最合适的低强度灭菌方案并分析了冷藏过程中的品质变化。结果 依据85、90、95、100℃下的灭菌曲线, 选择F值为5、6、8 min, 保温实验表明3种F值的产品均未胀袋, 但5 min、6 min下的菌落总数超出安全范围, 货架期较短, 选择F=8 min。对采用不同的杀菌时间温度组合进行灭菌的产品进行了色泽、质构及感官指标的分析, 发现色泽在95℃的灭菌温度下指标较好, 而质构在95~100℃的灭菌温度下均较好, 且消费者对于95℃的灭菌温度下喜好度较高, 因此确定选择95℃、23 min的灭菌条件。在4℃冷藏过程中, 相比于普通包装, 真空包装能够有效减缓品质劣化, 并且具有较高的感官评分。结论 选择F=8 min, 95℃、23 min杀菌条件结合真空包装, 可以延长酱大排的冷藏货架期并保持较好的品质。     

籼米甜酒的保鲜研究

对150 g塑料杯装新鲜甜酒分别采用热力和微波2种方法进行杀菌来研究新鲜甜酒的贮藏期,确定保持新鲜甜酒风味的杀菌强度,并对杀菌处理后的产品在5℃条件下进行稳定实验。结果表明,经70℃、21 min,75℃、16 min,85℃、7 min和80℃、12 min热杀菌及功率为800 W的微波炉处理55 s后的产品,其感官质量指标基本没有受到影响;85℃处理7 min的产品保鲜期可长达40 d;微波灭菌55 s的产品保鲜期可长达50 d。     

休闲盐焗鸽胗制品的研制及质量控制

以乳鸽胗为原料,通过盐焗、烘干、灭菌等工艺制作即食休闲盐焗鸽胗制品,并探讨腌制、盐焗、烘干、灭菌等工艺条件对盐焗鸽胗品质的影响。结果表明,乳鸽胗以3%盐、5%盐焗粉、1%酱油腌制过夜,然后漂洗净、焯水、烘干,用盐焗砂纸包裹,埋置于粗盐中,放入上下火均为170℃已预热的烤箱内焗制40min,再放入55℃的烘干机内烘干40min,将烘干后的乳鸽胗冷却后再进行真空包装,以110℃,15min的条件杀菌,所得产品口感软硬适中,风味独特,是一种优质的休闲肉制品。     

真空软包装榨菜和萝卜热力杀菌工艺研究

研究了杀菌工艺条件对真空包装榨菜和萝卜灭菌效果和感官品质的影响,防腐剂对真空包装榨菜和萝卜贮藏过程中微生物生长和品质的影响。结果表明,榨菜较适灭菌条件为95℃10min或90℃20 min,萝卜较适灭菌条件为85℃20min或90℃10min;加入0.05%苯甲酸钠可以大大延长产品的保质期。     

不同灭菌方法对诺丽果汁微生物及理化指标的影响

以诺丽果汁为研究对象,研究85℃×15 min、95℃×1.0 min、100℃×30 min、116℃×40 min和121℃×15 min 5种常用灭菌方式对诺丽果汁中微生物数量和理化性质的影响。结果表明:5种灭菌方式均能达到国家保健食品微生物安全标准的要求,但对诺丽果汁的理化性质影响不同,116℃×40 min和121℃×15 min灭菌后果汁颜色加深,不溶性沉淀明显增加,而另外3种灭菌方法则无显著影响。综合考虑,85℃×15 min、95℃×1.0 min的灭菌方式能在达到微生物安全要求的同时更好地保留诺丽果汁的特性,且节约成本,缩短时间,可考虑作为诺丽果汁首选的灭菌方式。     

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