牡丹籽油优势抗氧化剂研究

对牡丹籽油及其他5种植物油的基本理化指标进行了测定比较。牡丹籽油酸值(KOH)(2.034 mg/g)、过氧化值(0.286 mmol/kg)均在国标限值以内,碘值(I)185.8 g/100 g,说明其为干性油,皂化值(KOH)(188.1 mg/g)符合国家规定注射用油标准,较其他5种植物油品质好。选用迷迭香提取物、α-生育酚、TBHQ 3种抗氧化剂,并选择柠檬酸作为抗氧化增效剂,以不同比例组合加入牡丹籽油中,采用Rancimat法测定其氧化诱导时间(OSI)以确定优势抗氧化剂,结合温度外推法推测牡丹籽油货架期。最终遴选0.02%TBHQ+0.01%柠檬酸为优势抗氧化剂,推得20℃下添加此抗氧化剂的牡丹籽油货架期为3 737 h,约是未加抗氧化剂牡丹籽油的27倍,显著提高了牡丹籽油的耐贮藏性。     

野生香薷籽油脂肪酸组成及氧化稳定性研究

采用气相色谱对野生香薷籽油的脂肪酸组成进行分析测定,通过Rancimat氧化稳定性测定仪测定香薷籽油氧化稳定性,并分析比较不同抗氧化剂对香薷籽油的抗氧化效果。结果表明:香薷籽油中不饱和脂肪酸含量超过90%,其中亚麻酸含量达到58.65%;诱导期的对数与温度之间呈线性相关,香薷籽油在20℃时货架期为52.8 d,在抗氧化剂添加量相同的情况下,TBHQ的抗氧化效果最好;柠檬酸具有很好的增效作用,添加0.02%TBHQ+0.01%柠檬酸作为香薷籽油的抗氧化剂,在20℃时货架期为334.9 d,货架期延长282.1 d,抗氧化效果显著。     

亚麻籽油的保质期研究

通过考察不同光照条件、包装材料对亚麻籽油贮藏过程中过氧化值、酸价的影响,研究自然条件下亚麻籽油的保质期。结果表明:光照对亚麻籽油的贮藏性能有一定影响,避光有利于亚麻籽油的贮藏稳定性,散射和直射条件下对亚麻籽油贮藏稳定性的影响差别不大;对比PET瓶、透明玻璃瓶、棕色玻璃瓶、马口铁瓶不同包装材料贮藏亚麻籽油,玻璃瓶对亚麻籽油的贮藏性能优于马口铁瓶,马口铁瓶优于PET瓶,棕色玻璃瓶较透明玻璃瓶对亚麻籽油的贮藏稳定性有较大提升,棕色玻璃瓶储藏的亚麻籽油保质期可以达到18个月。     

牡丹籽油自氧化及抗氧化性能的研究

以超临界CO2萃取的牡丹籽油为研究对象,以过氧化值(POV)和硫代巴比妥酸值(TBA)为评价指标,考察温度、光照、空气及抗氧化剂对牡丹籽油氧化稳定性的影响。结果表明:温度、光照和空气均促进了牡丹籽油的氧化;0.02%浓度下,在牡丹籽油体系中添加抗氧化剂的抗氧化活性依次为:叔丁基对苯二酚(TBHQ)>茶多酚>二氢杨梅素(DMY)>迷迭香>V E;V E促进了牡丹籽油的氧化;添加0.02%TBHQ可使牡丹籽油在20℃时的预期储存时间由42d延至235d。      

2种酚类抗氧化剂对牡丹籽油氧化稳定性影响研究

通过Schaal烘箱实验,以过氧化值(PV)、茴香胺值(ρ-AnV)、全氧化值及脂肪酸组成为指标研究2种天然酚类抗氧化剂咖啡酸和阿魏酸及合成抗氧化剂TBHQ对牡丹籽油氧化稳定性影响,并建立牡丹籽油氧化动力学模型,以Rancimat法预测其货架期。研究表明:0.02%咖啡酸和0.02%阿魏酸对牡丹籽油都有一定的抗氧化效果,与不添加抗氧化剂相比货架期延长2.65、2.55倍,但较TBHQ仍有提升空间,几种抗氧化剂能力大小为TBHQ咖啡酸阿魏酸。咖啡酸、阿魏酸能够有效延缓牡丹籽油中α-亚麻酸等不饱和脂肪酸分解,提高牡丹籽油氧化稳定性和产品质量,能够作为高效、安全的天然抗氧化剂应用于油脂工业。     

不同方法提取的光皮梾木籽油氧化稳定性研究

研究水酶法、微波辅助萃取法和超临界CO2萃取法提取的光皮梾木籽油的自氧化程度随温度、时间的变化关系,以及抗氧化剂对光皮梾木籽油抗氧化效果。结果表明:超临界CO2萃取法提取的光皮梾木籽油在储藏过程中更易被氧化;在抗氧化剂添加量都为0.02%时,3种抗氧化剂对超临界CO2萃取法提取的光皮梾木籽油抗氧化作用的大小顺序为特丁基对苯二酚(TBHQ)维生素E丁基羟基茴香醚(BHA);柠檬酸和抗坏血酸都对抗氧化剂TBHQ表现出一定的抗氧化协同作用,且柠檬酸的协同效果优于抗坏血酸。添加0.02%TBHQ+0.01%柠檬酸能有效抑制该油在保存和销售过程中因氧化而产生的酸败,可使籽油在20℃下的预期贮藏时间由2个月延长到10个月。     

几种天然抗氧化剂对牡丹籽油氧化稳定性的影响

采用Schaal烘箱耐热试验法,以人工合成抗氧化剂二叔丁基羟基甲苯、丁基羟基茴香醚和特丁基对苯二酚等为阳性对照,研究茶多酚、苹果多酚、葡萄多酚、野葡萄多酚、牡丹籽多酚、生育酚、脂溶性迷迭香提取物和水溶性迷迭香提取物等8种天然抗氧化剂及2种增效剂(维生素C和柠檬酸)对牡丹籽油氧化稳定性的影响。研究以过氧化值为评价指标。结果表明,在国家允许添加量范围内,几种天然抗氧化剂均能提高牡丹籽油的氧化稳定性,但单独使用的效果要弱于人工合成抗氧化剂特丁基对苯二酚。其中脂溶性迷迭香提取物抗氧化效果较为理想,与合成抗氧化剂特丁基对苯二酚效果接近。维生素C与柠檬酸是抗氧化剂的良好增效剂,协同抗氧化作用显著,且维生素C的效果优于柠檬酸。复合抗氧化剂的抗氧化效果优于同等质量浓度的单一抗氧化剂,复合添加0.01%脂溶性迷迭香+0.01%茶多酚+0.02%维生素C、0.01%牡丹籽多酚+0.01%苹果多酚+0.02%维生素C和0.01%脂溶性迷迭香+0.01%茶多酚+0.02%柠檬酸均能显著减缓牡丹籽油的氧化速度,可使牡丹籽油的贮藏时间明显延长。     

茶多酚对牡丹籽油氧化稳定性的影响及货架期预测

以牡丹籽油为原料,以过氧化值为稳定性评价指标,采用Schaal烘箱加速氧化法探讨茶多酚添加量、抗氧化剂种类及贮存温度对牡丹籽油氧化稳定性的影响,根据Arrhenius经验公式推导出货架期模型,并对牡丹籽油货架期进行预测。结果表明,茶多酚在GB 2760—2014规定的添加量范围内对牡丹籽油的抗氧化作用随添加量增加而增大;添加0. 02%(以牡丹籽油质量计)的抗氧化剂对牡丹籽油的抗氧化效果依次为TBHQ BHT茶多酚,但对酸价的影响均不大;根据货架期模型可预测添加0. 02%茶多酚的牡丹籽油室温(25℃)下货架期为645. 30 h。     

几种天然抗氧化剂对牡丹籽油氧化稳定性的影响

以超临界CO2萃取的牡丹籽油为研究对象,采用schaal烘箱法,以过氧化值(POV)和硫代巴比妥酸值(TBA)为评价指标,考察茶多酚(TP)、二氢杨梅素(DMY)、迷迭香、V E4种天然抗氧化剂及2种增效剂(抗坏血酸V C和柠檬酸CA)对牡丹籽油氧化稳定性的影响。结果表明:在牡丹籽油体系中,0.02%茶多酚(TP)、0.02%二氢杨梅素(DMY)抗氧化效果较为理想;柠檬酸(CA)和抗坏血酸(V C)是TP及TP+DMY复合抗氧化剂的良好增效剂,协同抗氧化作用显著,且V C的效果优于CA;添加0.01%TP+0.01%DMY+0.01%V C复合抗氧化剂能显著减缓牡丹籽油的氧化速度,可使牡丹籽油在20℃时的预期储存时间由1.4个月延至12个月。     

抗氧化剂对杜仲籽油抗氧化性能影响的研究

采用Schaal耐热实验法,以过氧化值(POV)为指标,研究了温度、时间对杜仲籽油自氧化过程的影响及添加抗氧化剂对杜仲籽油抗氧化性能的影响。结果表明,温度、时间对杜仲籽油的自氧化过程有显著影响,且温度的影响更明显;叔丁基对苯二酚(TBHQ)对杜仲籽油具有良好的抗氧化效果,异VC和柠檬酸均对TBHQ与没食子酸丙酯(PG)复配而成的复合抗氧化剂表现出较强的抗氧化协同作用,异VC的抗氧化协同作用优于柠檬酸;添加0.02%TBHQ+0.005%PG+0.01%柠檬酸或0.02%TBHQ+0.005%PG+0.01%异抗坏血酸复合抗氧化剂,可使杜仲籽油在20℃条件下的预期贮藏时间从2个月延长至14～15个月。     

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