超声波协助提取茗荷红色素及其理化性质研究

采用单因素分析和正交实验L16(45),确定了超声波协助提取茗荷红色素的最佳工艺条件,并研究了茗荷红色素的理化性质.结果表明:最佳工艺条件为:提取剂的pH为1,料液比为1∶50,在50℃条件下,超声提取30min.茗荷红色素的耐热性好,耐光性较差,在酸性条件、氧化剂和蔗糖、维生素C、淀粉和柠檬酸中稳定性较好,在还原剂、苯甲酸钠和山梨酸钾中稳定性较差.     

仙人掌果红色素提取工艺及其稳定性研究

建立了海南野生仙人掌果实中红色素提取的最佳工艺条件,并对提取的红色素的稳定性进行了研究,为利用仙人掌果开发天然色素提供理论依据。红色素的提取工艺条件为：70％的乙醇溶液作为溶剂,提取温度为50℃,提取体系的料液比为1：20,提取pH5．0,提取时间1h。稳定性实验结果表明：仙人掌果红色素在pH3-5时红色素较稳定,色素随着光照的天数、氧化剂、还原剂浓度增加稳定性变差,红色素对金属离子Na^＋、Mg^2＋较稳定,而对Zn^2＋、Sn^2＋、Fe^3＋、Cu^2＋、Pb^2＋较不稳定。     

微波提取梵净山野生阳荷红色素及稳定性研究

为了研究微波法辅助提取梵净山野生阳荷红色素的最佳提取工艺,考察了提取时间、乙醇体积分数和料液比3个单因素的基础上,采用3因素3水平L9(33)正交试验法,以红色素的得率为考察指标,对微波提取野生阳荷的工艺进行了优化。结果表明:微波提取的最佳条件:提取时间3 min,乙醇体积分数60%,料液比1:25。另外,将红色素进行稳定性研究,结果表明:阳荷红色素在光照、温度、还原剂等条件下均具有良好的稳定性;而在强氧化剂(H2O2)中稳定性较差,因此,在使用阳荷红色素时必须注意强氧化剂的影响。     

茉莉花花蕾红色素的理化性质及其稳定性研究

为了更好地开发利用茉莉花花蕾红色素这一丰富资源提供科学的理论依据,为生产各种食用品、化妆品等色素新产品提供重要原料,研究从茉莉花花蕾中提取红色素的工艺条件和色素的稳定性.以茉莉花花蕾为原料,蒸馏水作提取剂,在室温下浸泡24 h,用紫外分析法研究色素的稳定性.茉莉花花蕾红色素在305 nm处有最大吸收峰.该色素水溶性良好,pH对茉莉花花蕾红色素的稳定性无明显影响.热稳定性较好,但pH=1,pH=5在40℃时,茉莉花花蕾红色素受到的影响最大.蔗糖和葡萄糖食品添加剂对茉莉花花蕾红色素无明显影响.该色素耐氧化剂、还原剂较强,但耐光较差,Fe3+、Cu2+对色素稳定性的影响最大.     

枣红素的提取及稳定性研究

对从残次枣中提取红色素及其稳定性进行了研究,结果表明:枣红素的最大吸收波长在656 nm处,最佳提取条件是最佳提取条件是在0.01 mol/L的NaOH,70℃,超声波提取1.5 h;对大枣红色素的稳定性分析中发现,该色素对光和热稳定;pH对大枣红色素的稳定性影响明显,在pH11附近色素的稳定性较好;金属离子K+、Na+、Fe3+、Mg2+对该色素的稳定性较好。     

大枣红色素的提取及其稳定性

用正交实验对大枣红色素的提取工艺条件进行了筛选，得出最优提取条件为：在80℃下，用16倍于枣皮粉的80％乙醇，超声波浸提30min。同时研究了光照、pH值、H2O2、Na2SO3等因素对色素稳定性的影响，结果表明大枣红色素除在强氧化剂H2O2和碱性环境中稳定性较差外，在其他条件下均具有良好的稳定性。     

甜菜红色素提取工艺及其稳定性研究

目的:优化出甜菜红色素的提取工艺,并对甜菜红色素的稳定性进行研究。方法:首先研究影响提取甜菜红色素的几个因素,包括最佳提取液、料液比、提取时间、提取温度、提取p H,并通过正交试验设计与分析优化最佳工艺参数;然后研究了甜菜红色素在光照、温度、护色剂和各金属离子下的稳定性。结果:甜菜红色素提取的最佳工艺条件:在常温下,以水作为提取溶剂、提取料液比为1∶5(g/m L),时间为5h,p H为4.5,并进行二次提取;其中溶剂p H是影响提取效果的主要因素。甜菜红色素的稳定性研究结果表明:光照和温度对甜菜红色素稳定性影响较大;护色剂苯甲酸钠对甜菜红色素有保护作用,1‰苯甲酸钠护色效果最好。各金属离子对甜菜红色素色泽无明显影响,Ca2+对甜菜红色素稳定性影响最小、Fe3+和Cu2+对色素稳定性影响最大,同时Fe3+和Cu2+还可降低甜菜红色素的色调。结论:利用该工艺提取甜菜红色素简单可行,光照和温度对其稳定性影响较大,金属离子影响较小,此研究可为甜菜红分离提取提供理论指导和参考依据。     

阳荷红色素的提取及稳定性研究

在单因素试验基础上用正交试验对阳荷红色素的提取工艺条件进行筛选，得出最优提取条件为：在60℃下，用150倍于阳荷粉的pH1的70％乙醇，恒温提取50min。同时研究自然光照、糖类、防腐剂、氧化剂和金属离子对色素稳定性的影响，结果表明，阳荷红色素除在防腐剂苯甲酸钠和山梨酸钾、强氧化剂H2O2及铁离子环境中稳定性较差外，在其他条件下均具有良好的稳定性。     

李子皮中红色素的提取及稳定性的研究

本研究以饮料加工厂废弃的李子皮渣为原料提取红色素，并对其工艺条件和色素稳定性进行了研究，结果表明：李子皮红色素提取的最佳工艺条件为：乙醇是最适提取溶剂，体积分数为50％，pH=2，室温(20～25℃)提取2h，经抽滤、减压浓缩、真空干燥，得黑紫色粉末状色素粗品。李子皮红色素是一种较为理想的无毒天然植物，     

叶子花红色素的提取及其稳定性研究

以叶子花苞叶为原料提取红色素,经正交试验选择最佳提取条件,并对光、温度、pH值、氧化还原介质、6种金属离子和4种食品添加剂对色素稳定性的影响进行了研究。结果表明,叶子花红色素为水溶性花青素的花色苷,在可见光区的最大吸收波长λmax=541nm。最佳提取条件为:以5%乙醇为提取剂,配料比为1:15,25℃下保温浸提3次,每次1h。该色素在70℃以下稳定性较好,对光的耐受性较差;色素在酸性条件下稳定,耐还原性强,但耐氧化性较差。6种金属离子中,Cu2+、Zn2+、Fe3+对色素有明显的破坏作用,而Mn2+、Mg2+、Al3+对色素稳定性较好,并有不同程度的护色作用。葡萄糖、NaCl、VC、苯甲酸钠对色素无不良影响。     

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.     

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     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.